Short Papers in Geology 

Hydrology, and Topography 

Articles 1-59 

GEOLOGICAL SURVEY RESEARCH 1962 

G E 0 L 0 G I CAL S U R V.E Y P R 0 FE S s· I 0 N A L P A P E R 4 5 0- B 

_$_cfentific notes and summaries of investigations 

prepared by members of the Geologic-' Wat~r 

Resources-' and Topographic n~·visions in the fields 

of geology-' hydrology-' topography-' and allied 

sczences 

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1962 
UNITED STATES DEPARTMENT OF THE INTERIOR 

STEWART· L. UDALL, Secretary 

GEOLOGICAL SURVEY 

Thomas B. Nolan, Director 

For sale by the Superintendent of Documents, U.S. Government Printing Office 

Washington 25, D. C. 
FOREWORD 

This collection of 59 short papers on subjects in the fields of geology, hydrology, topography, and related sciences is one of a, series to be relea~ed during the year as chapters of 

Professional Paper 450. The papers in this chapter report on the scientific and economic· 

results of current work by members of the Geologic, Topographic, and 'Vater Resources Division of the United States Geological Survey. Some of the pa.pers annom1ce new discoveries 

or present observations on problems of limited scope; other papers draw conclusions from 

more extensive or continuing investigations that in large part will be discussed in greater 

detail in reports to be published in the future. 

Chapter A of this series, to be published later in the year, will present a synopsis of 

results from a wide range of work done during the present fiscal year. · 

THOl\rAs B. NoLAN, 

Director. 

rn 
CONTENTS P~i:ge 

Foreword---------------------------------------~----------------------------------------------------------- JU 

GEOLOGIC STUDIES 

Economic geology 

l. Stratigraphic and structural controls of mineralization in the Taylor mining district near Ely, Nevada, by Harald 

Drewes----~-----~-------------------------------------------------------------------------------- B-1 .; 

2. Suggestions for prospecting in the Humboldt Range and adjacent areas, Nevada, by Robert E. Wallace and 

Donald B. Tatlock---------~----------------------------------------------------------------------- 3 I' 

Structural geology 

3. Possible detachment faults in the Teepee Creek quadrangle, Gallatin County, Montana, by Irving J. Witkind __ _ 6 

4. Hydrogeologic evidence of the extension of the E~;tst Range fault, Humboldt and Pershing Counties, Nevada, 

by Philip Cohen--------------------------------------~----------------------------~--------------- 9 ......,., 

Stratigraphy 

5. · Old metavolcanic rocks of the Big Creek area, central Idaho, by B. F. Leonard ____________________________ _ 11 

6. Angular unconformity between Mesozoic and Paleozoic rocks in the northern Sierra Nevada, California, by L. D. 

Clark, R. W. Imlay, V. E. McMath, and N.J. Silberling ______________________________________________ _ 15 .... 

7. Mesozoic age of metamorphic rocks in the Kings River area, southern Sierra Nevada, California, by James G. 

Moore and Franklin C. Dodge _____________________________________________________________________ _ 19 .. 

8. Red Bird Silty Member of the Pierre Shale, a new stratigraphic unit, by James R. Gill and William A. Cobban_ 21 

9. Note on post-Rustler red beds of Permian age of southeast New Mexico and west Texas, by James B. Cooper__ 24 

10. Volcanic rocks of Oligocene age in the southern part of the Madison Range, Montana and Idaho, by Warren 

Hamilton and Estella B. Leopold _______ -·- __________________________________________________________ _ 26 

11. Radiocarbon dates relating to a widespread volcanic ash deposit, eastern Alaska, by Arthur T. Fernald ________ "' 29 

Sedimentation and sedimentary petrology 

12. Origin of spherulitic phosphate nodules in bas.al Colorado Shale, Bearpaw Mountains, Montana, by W. T. Pecora, 

B. C. Hearn, Jr., and Charles Milton ________________________________________________________________ _ 30 

13. Stream directions in the Lakota Formation (Cretaceous) in the northern Black Hills, Wyoming and South Dakota, 

by William J. Mapel and Charles L. Pillmore---------------------------------------------------------- 35 

14. Formation and depositton of clay balls, Rio Puerco, New Mexico, by Carl F. Nordin, Jr., and William F. Curtis ___ ' 37 

15. Estimating porosity from specific gravity, by Philip Cohen _______________________________________________ _ 41 

16. Relation of volumetric shrinkage to clay content of sediments from the San Joaquin Valley, California, by A. I. 

Johnson and D. A. Morris __________________ ----_-- ___ -- ___ --- ___ -- ___________________ - ____ -- _______ _ 43 / 

Geomorphology 

17. Lower Pleistocene Prairie Divide Till, Larimer County, Colorado, by D. V. Harris and R. K. Fahnestock _____ _ 45 

18. Late Pleistocene and Recent erosion and alluviation in parts of the Colorado River system, Arizona and Utah, by 

Maurice E. Cooley ____ - ____________________ ------_----------_-_------- ____ - _________ -------_---- __ _ 48 

19. Relation of alluvial-fan size and slope to drainage-basin size and lithology in western Fresno County, California, by Willia1n B. Bull ___________________________________________________________________________________ _ 51 

20. Recent growth of Halemaumau, Kilauea Volcano, Hawaii, by Donald H. Richter, James G. Moore, and Robert .,.. T. Haugen---------------------------------------------------------------------------------------- 53 

Paleontology 

21. Marginal sea of middle Eocene age in New Jersey, by Stephen M. Herrick __ ------.-------------------------- 56 

22. Recent discoveries of the Cretaceous ammonite Haresiceras and their stratigraphic significance, by William A. 

Cobban------------------------------------------------------------------------------------------- 58 

23. Triassic fossils from the southern Klamath Mountains, California, by N . .J. Silberling and W. P. Irwin _________ _ 60 

Geophysics 

24. Thermal regime in the raised delta of Centrum S~, northeast Greenland, by Daniel B. Krinsley _______________ _ 62 

25. Magnetic anomalies· and ultramafic rock in northern California, by William P. Irwin and Gordon D. Bath _____ _ 65 

Mineralogy, geochemistry, and petrology 

26. Vanadium-rich garnet from Laguna, New Mexico, by Robert H. Moench ______ ... ____________________________ _ 67 

27. Thorium and uranium in some alkalic igneous rocks from Virginia and Texas, by David Gottfried, Roosevelt Moore, 

and Alice Caemmerer __ -~- ______________ · __________________________________________ ------ ___________ _ 70 

28. Saline features of a small ice platform in Taylor Valley, Antarctica, by Warren Hamilton, Irving C. Frost, and 

l)hilip T. Hayes _________________________________________________________________________ -:-. ________ _ 73 

v 
VI CONTENTS 

Analytical and petrographic methods Page 

B-76 

78 

"--29. Index of refraction measurements of fused Hawaiian rocks, by D. B. Stewart _______________________________ _ 

30. Determination of silica· in tektites and similar glasses by volatilization, by Maxwell K. Carron and Frank Cuttitta_ 

31. Use of La20a as a heavy absorber in the X-ray fluorescence analysis of silica rocks, by Harry J. Rose, Jr., Isidore 

Adler, and. Francis J. Flanagan ______________________________________________________________________ _ 

32. X-ray fluorescence determination of thallium in manganese ores, by Harry J. Rose, Jr., and Francis J. Flanagan_ 

Oceanography 

33. Electrode determination of the carbon dioxide content of sea water and deep-sea sediment, by G. W. Moore, C. E. 

Roberson, and H. D. Nygren _______________________________________________________________________ _ 

HYDROLOGIC STUDIES 

Ground water 

80 

82 

83 

34. Transitory movements of the salt-water front in an extensive artesian aquifer, by Harold R. Henry_____________ 87 

35. Estimating the effects of stream impoundment on ground-water levels, by J: E. Reed and M·. S. Bedinger_______ 88 

36. Movement of ground water beneath the bed of the Mullica River in the Wharton Tract, southern New Jersey, 

by S. M. Lang and E. C. RhodehameL _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 90 

37. Movement of perched ground water in alluvium near Los Alamos, New Mexico, by J. H. Abrahams, Jr., E. H. 

Baltz, and W. D. Purtyman_ _ _ __ _ _ _ ___ _ _ _ _ _ __ __ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ _ _ _ _ ___ _ ___ _ __ _ _ _ _ _ _ _ _ _ _ _ 93 

38. Source of ground-water runoff at Champlin Creek, Long Island, New 'York, by E. J. Pluhowski and I. H. 

Kantrowitz ____________________________________ :. __ ,... _________________________ .. ______________________ 95 

39. Relation of faulting to the occurrence of ground water in the Flagstaff area, Arizona, by J. P.. Akers____________ 97 

40. Method for measuring upward leakage from artesian aquifers using rate of salt-crust accumulation, by J. H. Feth 

and R. J. Brown---------------------~------------------------------------------------------~------ 100 

41. Seasonal temperature changes in wells as indicators of semi confining beds in valley-train aquifers, by Stanley E. 

Norris and Andrew M. Spieker __________________________________________________________________ ----·-_ 101 

42. Temperature-depth relations in wells as indicators of semi confining beds in valley-train aquifers, by Stanley E: 

Norris and Andrew M. Spieker_______________________________________________________________________ 103 

43. Water-yielding potential of weathered crystalline rocks at the Georgia Nuclear Laboratory, by J. W. Stewart____ 106 

44. Use of inflatable packers in multiple-zone testing of water wells, by F. C. Koopman, J. H. Irwin, and E. D. Jenkins 108 

Surface water 

45. Estimating days of continuously deficient discharge, by C. H. Hardison and J. R. Crippen ___________________ _ 

"'-46. Determination of tide-affected discharge of the Sacramento River at Sacramento, California, by S. E. Rantz ___ _ 47. Points of origin of_perennial flow in Georgia, by William J. Schneider_ ____________________________________ _ 

Quality of water 

48. Determination of boron in waters containing fluoride, by Jack J. Rowe ____________________________________ _ 

49. Limitations of the methylene blue method for ABS determination, by Cooper H. Wayman ____________ . _____ _ 

50. Hydrochemical facies in the "400-foot" and "600-foot" sands of the Baton Rouge area, Louisiana, by C. 0. Morgan 

and M. D. Winner, Jr _____________________________________________________________________________ _ 

51. Cation hydrochemical facies of ground water in the Englishtown Formation, New Jersey, by Paul R. Seaber ___ _ 

52. Use of Na/Cl ratios to distinguish oil-field from salt-spring brines in western Oklahoma, by A. R. Leonard and 

P. E. Ward----------------------------------------------------------------------------------------

53. Relation between aluminum content and pH of water, Beaver Creek strip-mining area, Kentucky, by George 

110 

Ill 

113 

114 

117 

120 

124 

126 

W. Whetstone and John J. Musser___________________________________________________________________ 127 

54. Chemical quality of surface waters in the Brazos River basin, Texas, by Burdge Irelan and H. B. Mendietta_____ 129 

55. Chemical quality of ground water in St; Thomas, Virgin Islands, by I. G. Grossman--------------------'------ 131 

TOPOGRAPHIC STUDIES 

Photogrammetry 

56. A test of the direct geodetic restraint methoq of analytical aerotriangulation, by Robert C. Eller and Morris L. 

McKenzie_------------------------------------------------------------------------------------------

57. Research activity with the U-60 orthophotoscope, by Marvin B. Scher _____________________________ · _____ ----

Field control 

133 

135 

58. Research on target design for photoidentification of control, by David Landen __ ~_____________________________ 137 

59. New elevation meter for topographic surveys, by Julius L. Speert____________________________________________ 141 

INDEXES 

Subject------------------------------------------~-------------------------------------------------------- 143 

Author------------------------------------------------------------------------------------~-------------- 145 
.. 

~· . 

... 

GEOLOGICAL SURVEY RESEARCH 1962 

SHORT PAPERS IN GEOLOGY, HYDROLOGY, AND TOPOGRAPHY, 

ARTICLES 1-59 

GEOLOGIC STUDIES 

ECONOMIC GEOLOGY 

1. STRATIGRAPHIC AND STRUCTURAL CONTROLS OF MINERALIZATION IN THE TAYLOR MINING ,DISTRICT 

NEAR ELY, NEVADA 

By HARALD DREwEs, Denver, Colo. 

The Taylor minipg ·district lies on the west flank of 

the Schell Creek R~inge 15 miles soutlwast of.· Ely ai).d 

5 miles nortlnvest of Connors Pass; · The district lias 

produced $1 to $2 million worth of silver, and a little 

gold, copper, lead, zinc, and anti1n~ny since 1883, of 

which about half has been produced since 1935. 

The ore occurs sporadically in highly silicified rocks. 

Stratigraphic and structural controls of the silicified 

bodies determined through the geologic mapping of the 

Connors Pass 15-Ipinute quadrangle are reported here. 

Sulfides ( stibnite, galena, sphalerite, and possibly 

chalcocite) are seen in few hand specimens; no silver 

wn,s recognized in the field. Spectrographic analysis 

of 40 sn,mples fr01n 7 pits shows that the silver content 

generally increases eastward, or stratigraphically upward, and that silver is more closely associated with 

n.ntimony than with other base n1etals. The distribution of the ore within the silioified bodies was not 

further investigated. 

The sequence of the rocks and their degree of mineralization a.re tabulated below; the age of the rocks 

appears on the map explanation. Silification is restr~cted to limestoi1e, and preferentially to thin-bedded 

or. ~haly limestone beneath thick shnJe. formations. The 

map· (fig: 1.1) illustrates the stratigdtphic m)d structtl.ral controls of the main silicified bodies. 

Fonna.tion Deg·r.ee· oj mi.neralization 

GraveL------------------· Barren. 

Latite and dacite flows and Do. 

tuffs. 

Granophyric rhyolitic 

dikes. 

Kaolinized but not mineralized. 

Ely Limestone ____________ , Barren. 

Chainman Shale___________ Do . 

. Joana T..~imestone __________ Many small lenses of silicified rock 

near the· top of the formation, 

bearing Sb and Ag. 

Pilot Shale ________________ Barren. 

Guilmette Formation: 

Member C------------- Large silicified bodies, especially in 

the upper half of the unit, bearing Ag, Au, On, Pb, and Zn. 

Member b------------- Few, scattered, small silicified 

bodies. 

Member a------------· Barren. 

Simonson Dolomite_______ Do. 

Sevy Dolomite___________ Do. 

B-1 
B-2 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

R. 65 E. 

T. 

14 

N. 

EXPLANATION 

Gravel 

Latite and dacite flows 

and tuffs 

[2] 

Granophyric rhyolite dikes 

Ely Limestone 

Chainman Shale 

Joana Limestone 

Pilot 

-

Shale 

Guilmette Formation 

Dgc, member c 

Dgb, member b 

Dga, member a 

Simonson Dolomite 

Sevy Dolomite 

ULJ 

Silicified rock 

------ Contact 

-------6--

Fault 

Dotted where concealed. U, upthrown 

side; 

~ 

D, downthrown side 

Thrust fault 

Teeth on overriding block 

4~ 

S,trike and dip of beds 

70 

+ 

>-

a:: 

n 

z 

<( 

z 

~ 0 

Strike and dip of overturned beds 

l"l 

Shaft 

~ 

Large pit 

X 

Prospect and small pit 

y 

Adit 

FIGURE 1.1.- Geologic map of the Taylor mining district near Ely, Nev. Silver ore occurs in some silicified bodies. 
... 

... 

ARTICLE 2 B-3 

The silicified limestone is in part localized along 

normal faults that trend north to northeast and have 

displacements of a. few tens of feet to several hundreds 

of feet. Silicified rock along these faults is locally 

sheared. Much smaller silicified bodies are found elsewhere in the quadrangle where norm.al faults of similar 

trend cut only the 1niddle or middle and lower plates 

of the three rna.jor thrust plates, and the bodies are 

probably contemporaneous with the thrusting. A postm.inernJization normal fault with many hundreds to possibly several thousands of feet of .displacement trends 

northwest close to the foot of the range and brings young 

unmineral.ized rocks down against older mineralized 

rocks.· At least smne of the movement on th1s fault 

postdates the latite and dacite flows and related sediments, probably of middle Tertiary age, found along 

the edge of the valley. 

~fany thick, short rhyolitic dikes with northerly and 

northeasterly strikes n.re concentrated in the Taylor 

district, suggesting that they are related to the mineralizn.tio.n. The feldspars of all the dikes are strongly 

kaolinized, but none of the dikes are strongly silicified 

or mineralized. The concentration of dikes near the 

mineralized bodies and the parallelism between many 

dikes, older faults, and silicified bodies suggests that· 

the stresses in the rocks were similar during formation 

of the dikes and m_ineralized bodies, and that the silicification and the emplacement of the dikes took place at 

about the same time. The dikes are porphyritic, with 

phenocrysts of quartz, unlike that· of the nearby rhyolitic volcanic rocks. The dikes may be re]a;ted. to other 

porphyry intrusive bodies accompanied by mineralization in eastern Nevada. 

In conclusion, the ore-bea.ring silicified bodies are 

localized near the tops of the Guilmette Formatimi and 

the Joana Limestone and along nonnal faults. The 

same horizons in adjacent downfaulted blocks, and 

shaly limestone in the n1iddle member and at the base 

of the. lower member of the Guilmette Formation in 

the mineralized area, should be explored. The rhyolitic 

dikes are concentrated near the mineralized bodies and 

are probably related to them temporally, and possibly 

genetically. 

2. SUGGESTIONS FOR PROSPECTING IN THE HUMBOLDT RANGE AND ADJACENT AREAS, NEVADA 

By RoBERT E. WALLACE and DoNALD B. TATLOCK, Menlo Park, Calif. 

Work done in cooperation with the Nevada Bm·ea1t of Mines 

During recent geologic investigations in the Humboldt Range, northwestern Nevada, we found that for 

many of the mineral deposits, a distinctive geologic setting can be defined that should serve as a guide in the 

search for additional deposits both in the Humboldt 

Range and in neai"by localities of similar geologic setting. In the following suggestions for prospecting, 

broad geologic areas are primarily defined, and within 

these areas ·locnl structures must be considered. 

The geologic structures and lithologic units of the 

range that are referred to in this article are shown on 

preliminary geologic maps of the Buffalo Mountain 

quadrangle (vV all ace and others, 1959) and of the 

Unionville qua.draJ1gle (vVallace and.others, 1962; Wallace and others, 1960, fig. 133.1, p . .B292). These maps 

are a necessary adjunct to the following discussion. 

Silver.-The Weaver Rhyolite and immediately underlying parts of the Rochester Rhyolite are the host 

rocks for the Rochester and Pa,ckard silver districts 

(l{nopf, 1924). In addition, the larger bodies of rhyolite porphyry, which are believed to be feeders for the 

'Veaver Rhyolite, commonly have silver related to them. 

This type of mineralization is believed to be genetically 

rehtted to the igneous rocks and thus is of Permia11 ( ~) 

or Early Triassic age. 

In prospecting, pay special attention to the Weaver 

Rhyolite and the rhyolite porphyry stocks that are in a. 

crude line between South American Canyon a.nd Unionville. The silver minerals characteristic of the area 

are difficult to identify by naked eye and commonly 

are "in rather indistinct silicified zones in the rhyolite .. 

Without thorough testing, such silver-bearing zones 

may easily be overlooked. Best values are probably 

within a few hundred feet of the surface . 
B-4 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

Silver-scheelite.-A distinctive type of deposit containing conspicuous quartz veins, which in turn conta.in 

'inconspicuous silver minerals and sparse scheelite, is 

found in the Prida Formation of Middle Triassic age. 

This is a limy unit resting on volcanic rocks of the 

l{oipato Group. The Arizona (Cameron, 1939), Rye 

Patch (Ransome, 1909, p. 43-44) and Relief (Schrader, 

1915, p. 362) mines characterize this type of deposit. 

The possibility exists that the silver in these deposits 

was remobilized from Permian ( ? ) and Early Triassic 

deposits by igneous activity in Late Jurassic or Early 

Cretaceous time. 

The entire outcrop band of the Prida Formation 

warrants prospecting for this type of deposit, but exam.ine particularly the limestone ·adjacent to or near 

rhyolite porphyry intrusive bodies of Weaver Rhyolite. 

Scheelite-beryl-fluorite.-Scheelite deposits throughout Pershing and Humboldt Counties are related to 

granitoid rocks generally of granodioritic or· quartz 

monzonitic composition of Late .Jurassic or Early Cretaceous age that have intruded limestone bodies. The 

Little (Oreana) tungsten deposits (Kerr, 1938; Vitaliano, 1944) on the west flank of the Humboldt Range 

are characteristic and are in veins in limestone near 

quartz monzonite and related aplite bodies. I-Iigh-grade 

pods have formed in limestone immediately below 

metadiorite sills. Beryl, and in some places fluorite, 

occupies the same or similar veins in the same setting. 

Limestone bodies intruded hy granodiorite or quartz 

monzonite should be examined for scheelite by ultraviolet light. In addition, the combination of beryl, 

fluorite, and scheelite suggests a similarity to the Mt. 

Wheeler mine (Stager, 1960; Whitebread and Lee, 

1961) where beryl and less conspicuous beryllium minerals such as phenacite have been found. The search 

for less conspicuous beryllium deposits may require 

sp~cial techniques such as use of a bery llometer. 

Lode gold.--Quartz veins containing native gold ·are 

related to the swarms of rhyolite porphyry dikes in the 

headwaters of Limerick, Sacramento, Spring, North 

American, and South American Canyons (Knopf, 1924, 

p. 51-52; Schrader, 1915, p. 354). The veins are generally not in the rhyolite porphyry dikes but are in the 

same host rocks as the rhyolite porphyry dikes. 

Any quartz vein cutting the Limerick Greenstone or 

the Rochester Rhyolite in the general vicinity of rhyolite porphyry intrusive bodies should be considered a 

potential gold prospect. 

Placer gold.-Drainage channels that cross potential 

lode-gold areas may contain placer gold. For example, 

Limerick, Spring, and North and South American Canyons (Knopf, 1924, p. 58; Schrader, 19·15, p. 368) are 

known to contain placer gold. 

Situations where several stages of concentration 

might have occurred, for example channels within channels, offer better than average possibilities of successful 

prospecting. 

Cinnabar and st-ibnite.-Cinnaba.r and stibnite deposits are believed to be related to late Tertiary and 

Quaternary basin-range faults that blocked out the 

range. It is also believed that the main deposits were 

formed during an early part of this period of faulting, 

perhaps at about the same time that basaltic and andesitic lavas were extruded. Bailey and Phoenix ( 1944, 

p. 29) point out, however, that basalt itself has not 

proved. to be a good host rock and that cinnabar deposits in the more rec-ently active fault zones, commonly 

accompanied by hot springs, have not proved to be of 

economic value. 

The lower flanks and margins of the range are promising for prospecting, particularly those flanks on which 

both limy formations and basalt flows are found; the 

part of the flank basin ward from faults of late Tertiary 

age, such as the Fitting fault, is particularly promising. 

'Vi thin such· geologic settings, more detailed prospecting guides, such as rock alteration (Bailey and Phoenix. 

1944, p. 29), may be helpful. 

/ron.-Magnetite and hematite are clearly related 

to large altered dioritic bodies and to associated andesitic rocks throughout much of Nevada (Reeves and 

J(ral, 1955). There is growing evidence that these may 

be of Early Cretaceous or possibly Late Jurassic age. 

The magnetite an9, hematite are in veins and in disseminated masses through the diorite. The trends of 

iron-bearing veins in the Buena Vista Hills area of 

Pershing County are somewhat random. 

Dioritic and andesitic bodies of Mesozoic age should 

receive attention in prospecting. Within these bodies 

additional iron deposits 1night be revealed by magne~c 

and gravity surveys, both where these bodies crop out, 

and where. these rocks might be concealed by basin fill 

Gravity anomalies might reveal nonmagnetic hematite 

bodies. 

Li1nestone.-Analyses. of limestone of tl1e Prida and 

Natchez Pass Formations of Middle and Late Triassic 

age suggest large limestone bodies of sufficient quality 

for Portland cement. Samples containing as much as 

55 percent CaO, less than 0.2 percent Si02, and less 

than 0.5 percent MgO have been found. 

Inasmuch as there appear to be large quantities of 

limestone of cement quality, the economic considera-

. tions of transporta!ion, fuel, and ease of quarrying must 

receive attention before any part of the limestone is 

selected for detailed testing. 

Perlite.-N umerous bodies of perlite were found in 

the lower part of the rhyolite flows and tuffs of Tertiary 
'' 

ARTICLE 2 B-5 

age. At least one such body is being 1nined in the 

Trinity Range. 

The contact between Tertiary rhyolite and underlying rocks in the 'Vest IIumboldt and Trinity Ranges 

warrants prospe~ting. 

/i,,valJO'rites.-The basins around the IIumboldt Range 

contain halite and conceivably may contain other evapOI'ites such as borates. Relatively little is know1i. of 

the buried deposits in the basins, although one hole was 

drilled in Carson Sink during the search for potash 

before the first 'Vorld 'Var (Gale, 1911). D. F. Hewett 

(oral communication) has found that boron is more 

abundant in hot springs of western Nevada than in hot 

springs of eastern Nevada, and this fact together with 

the relative abundance of boron aluminum silicates 

such ns tour.maJine and dumortierite in the I-Iumboldt 

Hange is suggestive of a boron-rich province. Gravity 

studies by Don M:abey of the U.S. Geological Survey 

(written comnu1nication, 1960) indicate that the basin 

fill is at least 8,000 feet thick in Buena Vista Valley 

nnd more than 4,000 feet thick between the Humboldt 

River HJld the west fta.nk of the Humboldt Range in 

the vicinity of Rye Patch. 

Too little is known of the geologic history of the 

bn.sins to suggest which locality is most favorable for 

prospecting. 

Sand and g1·avel.-Along the borders of ancient Lake 

Lahontan, which occupied the basins around the H;runboldt. Range, mn.ny beaches and bars were f9rmed that 

contn.in wn.ve-sorted gravel and sand. During lowWit-ter levels and n.fter the lake had. completely dried 

up, winds gathered much of the s~tnd into dunes. Such 

sn.nd and gravel from which the fine particles have been 

sorted by the action of waves and winds have properties 

that m.ake then1 suitable for economic use. 

Many beaches and bars of Lake Lahontan, as well 

ns saJld dunes, are clearly visible on aerial photogra.phs 

of the Humboldt Range and surrounding b~tsins. These 

photographs are availruble from the U.S. Geological Survey and Army Map Service. Many of th~se potential 

sources of sand and gravel are near highways and railroads ru1d thus may have economic value. Examination 

of aerial photographs may save time in the search for 

sand and gravel. 

REFERENCES 

~ailey, E. H., and Phoenix, b. A., 1944, Quicksilver deposits 

in Nevada: Nevada Univ. Bull., v. 38, no. 5, Geology and 

Mining ser. 41, 206 p. 

Cameron, E. N., 1939, Geology and mineralization of the northeastern Humboldt Range, Nevada: Geol. Soc. America Bull., 

v. 50, no. 4, p. 563-634. 

Gale, H. S., 1911, The search for potash in the United States: 

U.S. Geol. Survey Bull. 530-A, p. 3-27. 

Kerr, P. F., 1938, Tungsten mineralization at Oreana, Nevada: 

Econ. Geology, v. 33, no. 4, p. 390-427. ' 

Knopf, Adolph, 1924, Geology and ore deposits of the Rochester 

district, Nevada: U.S. Geol. Survey Bull. 763, p. 1-78. 

Ransome, F. L., 1909, Notes on some mining districts in Humboidt County, Nevada: U.S. Geol. Survey Bull. 414, p. 1-75. 

Reeves, R. G., and Kral, V. E., 1955, Geology and iron .ore deposits of the Buena Vista Hills, Churchill and Pershing 

Counties, Nevada, pt. A of Iron ore· deposits of_ Nevada: 

Nevada Bur. Mines Bull. 53, p. 1-32. 

Schrader, F. C., 1915, The Rochester mining district, Nevada: 

U.S. Geol. Survey Bull. 580, p. 325-372. · 

Stager, H. K., 1960, A new beryllium deposit at the Mount 

·wheeler mine, White Pine County, Nevada: Art. 30 in 

U.S. Geol. Survey Prof. Paper 400-B, p. B70-B71. 

Vitaliano, C. J., 1944, Contact metamorphism at Rye Patch, 

Nevada: Geol. Soc. America Bull., v. 55, no. 8, p. 921-950. 

Wallace, R. E., Silberling, N. J., Irwin, W. P., and Tatlock, D. B., 

1959, Preliminary geologic map of the Buffalo Mountain 

quadrangle, 'Nevada: U.S. Geol. Survey Mineral Inv. Field 

Studies Map MF-220. 

Wallace, R. E., Tatlock, D. B., and Silberling, N. J., 1960, Intrusive rocks of Permiah and Triassic age in the Humboldt 

Range, Nevada: Art. 133 in U.S. Geol. Survey Prof. Paper 

400--B, p. B291-B293. 

·wallace, R. E., Tatlock, D. B., Silberliug, N.J., and Irwin, ,V. P., 

1962, Preliminary geologic map of the Unionville quadrangle, Nevada: U.S. Geol. Survey Mineral Inv. Field 

Studies Map MF-245. 

·Whitebread, D. H., and Lee, D. E., 1961, Geology of the Mount 

Wheeler mine area, White Pine County, Nevada: Art. 193 

in U.S. Geol. Survey Prof. Paper 424-C, p. C120-C122. 
B-6 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

STRUCTURAL GEOLOGY 

3. POSSIBLE DETACHMENT FAULTS IN THE TEPEE CREEK QUADRANGLE, GALLATIN COUNTY, MONTANA 

By IRVING J. WrTKIND, Denver, Colo. 

Two folded parallel bedding faults, similar in many 

respects to the Heart Mountain and South Fork detachment faults of northwestern Wyoming (Pierce, 1957) 

are exposed in the Tepee Creek quadrangle, Gallatin 

County, southwestern Montana. The extent of these 

newly discovered faults is unknown; to date, they have 

been traced for an outcrop length of about 30 miles 

(fig. 3.1). Their persistence and continuity suggest that 

they are of ·regional extent. 

One, and locally both of the faults are well exposed 

in the northern third of the quadrangle, particularly 

in the cirque at the head of Bacon Rind Creek (fig. 3.2) 

and along the flanks of Snowslide (fig. 3.3), Monument, 

and Red Mountains. Elsewhere they are poorly exposed beneath talus and dense foliage. 

These two newly discovered faults, one stratigraphically above the other, bound a segment of the Madison 

Group (Mississippian) which rests on undifferentiated 

units tentatively correlated with the Maywood( n 

(Devonian) and Red Lion{~) (Cambrian) Formations. 

The Jefferson Dolomite (Devonian) and Three Forks 

(Devonian and Mississippian) Formation, which total 

about 500 feet in thickness, are normally between the 

Madison and these undifferentiated units in surrounding areas (Hadley, 1960; Robinson, 195g), but they have 

been cut out by the lower fault; here named the Cone 

Peak fault. 

The similarities between the Cone Peak and Heart 

Mountain faults are marked, and far exceed the dissimilarities. Thus, both faults cut out Jefferson and 

Three Forks strata, are at almost the same stratigraphic 

horizon-the top of the Cambrian, and tend to follow 

stratigraphic horizons. Further, along both faults, 

an upper plate of younger rocks rests on older rocks. 

One great dissimilarity, however, is that the Cone Peak 

fault has been folded and faulted along with the overlying and underlying strata, whereas, at least locally, 

the Heart Mountain fault is nearly horizontal and rests 

on folded rocks. One explanation for this difference 

is that the bedding faults in the Tepee Creek area began 

as detachment faults, but have since been modified by 

one or more orogenic episodes. 

The upper plate of the Cone Peak fault is, at a minimum, 12 miles long and about 4 miles wide, but it is 

only about 550 feet thick. Its shape, therefore, is that 

of an elongate, broad, extremely thin sheet. This unusual ratio between extent and thickness also marks 

the upper plate of the Heart Mountain fault, for it is 

111°15' 111 ·oo· 

5 0 5 MILES 

FIGURE 3.1.-Index map of parts of southwestern Montana and 

northwestern ·wyoming. Tepee Creek quadrangle shown by 

hrichures. Barbed lines show approximate outcrop of Cone 

Peak fault (solid barbs) and Redstreak Peak faults (open 

barbs). Barbs are on upper plate. 

/ 

I 

~1 ' 

.(' 
ARTICLE 3 B-7 

FIGURE 3.2.-View looking southwest into cirque at the head of Bacon Rind Creek showing the general relations between the 

Cone Peak and Redstreak Peak faults. The upper plate of the Cone Peak fault consists of parts of both the Lodgepole 

and Mission Canyon Limestones of the Madison Group (Mm) (Mississippian). The lower plate is formed by Cambrian 

and Devonian (D£) strata (undifferentiated), and the normal Cambrian sequence of this part of southwestern Montana. 

From the oldest to the youngest these Cambrian strata include the Meagher Limestone ( £m), Park Shale ( £pa), and 

Pilgrim Limestone (£p). The upper plate of the Redstreak Peak is composed of the Madison Group (Mm), Amsden 

Formation ( IPMa), and Quadrant Formation ~ pq). 

E. w. 

FIGURE 3.3.-View looking south at valley wall near Snowslide Mountain showing tight fold in the Madison (Mm) of the 

upper plate of .the Redstreak Peak fault. Part of the upper plate of the Cone Peak fault (Mm) is exposed below the 

Redstreak Peak fault. 
B-8 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

very thin in comparison to its horizontal extent (Pierce, 

1957, p. 593). The upper plate of the Cone Peak fault 

consists of about 310 feet of thin-bedded cherty fossiliferous iimestones tentatively assigned to the upper 

part of the Lodgepole Limestone of the Madison Group, 

and 240 feet of thick-bedded to massive oolitic limestones, provisionally assigned to the basal part of the 

Mission Canyon Limestone of the Madison. The stratigraphic units involved, therefore, are from the middle 

of the Madison Group. 

Normally these beds conform to the attitude of the 

over1ying .and underlying strata, but locally they are 

ihtensely deformed by folds and small high-angle 

normal and reverse faults that do not extend into the 

strata that hound the upper plate. Similar high-angle 

faults are common in the upper plate of the Heart 

Mountain fault (Pierce, 1957, p. 593). These folds 

and faults in the upper plate of the Cone Peak fault 

suggest that a segment of the Madison Group was detached from the underlying strata and deformed independently, possibly as a result of gravitational gliding, much as proposed for the Heart Mountain fault 

(Pierce, 1957, p. 615). 

The upper fault, here called the Redstreak Peak fault 

(fig. 3.2), is the top of the upper plate of the Coile Peak 

fault. Commonly, the Lodgepole Limestone forms the 

upper plate of the Redstreak Peak fault, ·although at 

one locality a thin sliver of the Sappington Sandstone 

Member of the Three Forks Shale (Devonian and Mississippian) may be between the fault plane and the 

Lodgepole Limestone. The full Paleozoic and Mesozoic 

stratigraphic sequence common in southwestern Montana continues unbroken above the Lodgepole Limestone. The beds above the Redstreak Peak fault locally 

are deformed into tight folds with axial planes that dip 

west, suggesting that this plate moved eastward (fig. 

3.3). The Redstreak Peak fault, like the Cone ~eak 

fault, has been deformed along with the confining 

strata. 

Both faults normally are concealed by debris and 

foliage. Where exposed, they appear to be smooth and 

undulatory. Locally, a breccia is below the Cone Peak 

fault in the uppermost beds of the Maywood ( ? ) 

Formation. 

The two faults seem to have formed essentially as 

low-angle nearly horizontal bedding-plane faults that 

here and there cut across the bedding. · As yet, neither 

of these faults has been found to extend across an erosion surface in the manner of the Heart Mountain 

thrust (Pierce, 1957, p. 598). 

Little is known about the direction of movement of 

the faults hut the similarity of these faults to the detachment faults of northwestern 1Vyoming indicates 

that the faults in the Tepee Creek area may have formed 

.in the same manner, at about the sam~ time, and from 

the same upland. If so, the movement on the -Tepee 

Creek faults may have been southwestward from an 

ancestral high centered near the north edge of Yellowstone National Park. The overturned folds in the beds 

above the Redstreak Peak fault (fig. 3.3), however, suggest that the sliding was chiefly eastward. Possibly 

the same direction of movement occurred along the 

Cone Peak fault. 

The age of the faults is known only within rather 

broad limits, although they probably formed at abowt 

the same time. They appear to represent the first 

-major structural event involving consolidated sedimentary strata in the Tepee Creek area. They are almost 

certainly younger .than the youngest strata (Triassic) 

conformable with the Madison, and are very likely postEarly Cretaceous. As they are folded and faulted 

along with the overlying and underlying strata, they 

are older than the regional folding which involves rocks 

as young as Paleocene or early Eocene. Their age, 

therefore, is provisionally set as post-Early Cretaceous 

and pre-early Eocene. By comparison, the age determined for the Wyoming detachment faults is early 

Eocene (Pierce, 1957, p. 624). 

REFERENCES 

Hadley, J. B., 1960, Geology of the northern part of the,Grave.Hy 

Range, Madison. Ooulllty, Montana, in Billings Geol. Soc. 

Guidebook 11th Ann. Field Conf., West Yellowstone-earthquake area, 1960: p. 149-153. 

Pierce, W. G., 1957, Heart Mountain and South Fork detachment thrusts of Wyoming: Am. Assoc. Petroleum Geolo· 

gists Bull., v. 41, no. 4, p. 591-626. 

Robinson, G. D., 1959, The d-i·sturbedi belt in the Sixteenm~le area, 

Montana, in Billings Geol. Soc. Guidebook lOth Ann. Field 

Conf., Sawtooth-disturbed belt area, 1959, p. 34-40. 

·-4 
ARTICLE 4 B-9 

4. HYDROGEOLOGIC EVIDENCE OF THE EXTENSION OF THE EAST RANGE FAULT, HUMBOLDT AND 

PERSHING COUNTIES, NEV A'DA 

By PHILIP CoHEN, Carson City, Nev. 

Wo·rk done in cooperation with the Nevada Department of ConservatiO'n and Natural Resottrces 

Faults and associated phenomena are known to influence the occurrence and movement of ground water, 

and apparent hydrologic anomalies commonly are explained on the basis of inferred faults. Less commonly, 

n.s in this report, hydrogeologic evidence is used to 

demonstrate the existence or extension of a fault. 

A northward-trending, westwa.rd-dipping, high-

. angle normal fault, herein referred to as the East Range 

fault (fig. 4.1) borders the western slope of the East 

Range, Humboldt and Pershing Counties, Nev., where 

it was mapped by Ferguson, Muller, and Roberts 

(1951). Evidence of the fault includes fault scarps, 

displaced strata, slickensides, qrecciated zones, and 

hydrothermal mineralization. 

During current hydrologic studies, about 175 test 

borings were drilled in the unconsolidated deposits of 

the Humboldt River basin near Winnemucca, Nev. 

Some of the hydrogeologic data thus collected suggest 

that the ·East Range fault extends at least about 2 miles 

farther northward than previously mapped. 

The l(rum Hills, the unnamed hills north of the 

I-Iumboldt River, and that· part of the East Range 

shown in figure 4.1 are composed of dense sedimentary 

and igneous rocks of Mesozoic age and basaltic lava 

flows of late Tertiary or Quaten1ary age. These rocks 

generally have low permeability and therefore do not 

transmit appreciable amounts of water, except perhaps 

through fractured zones. 

Most of the ground water of the area is in relatively 

tmconsolidated sedimentary deposits that range in age 

from Pliocene to Recent. These strata include fanglomerate of Pliocene or Pleistocene age, lacustrine deposits 

of Pleistocene Lake Lahontan age, and fluviatile and 

subaerial flood-plain deposits of Recent age. 

The fanglomerate ranges from well-sorted moderately permea;ble sand and gravel to poorly sorted relatively impermeable slope wash. The Lake Lahontan 

deposits include three stratigraphic units: A so-called 

lower silt and clay, a medial gravel, and an upper silt 

and clay; the lower two units are recognized only in the 

subsurface. The lower silt and clay unit, whose thic.kness is uncertain, and the upper silt and clay unit, which 

is about 55 feet .thick, consist largely of dense relatively 

impermeable silt, clayey silt, and clay. The medial 

gravel, whose maximum thickness is about 150 feet, 

consists of well-sorted highly permeable sand and 

gravel. The flood-plain deposits range from highly 

permeable stringers·. of sand and gravel to relatively 

impermeable lenses of silty clay and clay. 

The water-level contours of figure 4.1 show the shape 

of the piezometric surface in December 1960 and suggest that the principal ground-water movement is westward and southwestward, roughly parallel to the course 

of the Humboldt River. 

Streamflow of the Humboldt River ·tends to increase, 

especially during periods of low flow, between tlie east 

margin of the mapped area shown on figure 4.1 and staff 

gage D. The increase of streamflow, about 5 to 6 cubic 

feet per second, is largely a result of the discharge of 

ground-water underflow from Grass Valley into the 

Humboldt River. Part of the increase, however, may 

be due to a partial ground-water barrier beneath the 

channel of the Humboldt River, the barrier being related to the northward extension of the East Range 

fault. 

Other hydrogeologic evidence which suggests that the 

East Range fault ·probably extends farther northward 

than previously mapped includes (a) an area of ri'sing 

thermal ground water partly indicated by springs 1 

and 2, (b) dense siliceous rock exposed in the flood 

plain about 300 feet north of well 5, (c) thermal water 

and iron oxide-coated pebbles found in well 5, (d) 

intense hydrothermal alteration of the material penetrated in well 3, (e) the occurrence of a bedrock high 

as indicated by the material penetrated in well 4, and 

(f) the dissolved-solids content of the waters of the 

area. 

A local ground-water mound, as defined by the water 

levels at springs 1 and 2 and well 3, is about 100 feet 

above the regional water table. The temperature of the 

water at springs 1 and. 2 and well 3 is 83° F, 82° F, 

and 82° F respectively, about 20° 'F to 25° F warmer 

than the water in all but one of the other wells shown 

in figure 4.1. The relatively high temperature of the 

thermal waters presumably is clue largely to the contribution of deeply circulating ground wate~ moving 

through fractured zones associated with the fault and 

discharging into the alluvium. 

Calcareous and siliceous spring sinter is exposed at 

and near the orifice of spring 1. 'The previously men-
QTt 

y . -,. L·-" I"" > {. <" L. v ..J v '" 7 r- r- .J < '1 / jv I' j.. -,.-JL1 t-.J ,\ 

,., v r- r- .,.-I) .., '- 'l 1\ 

I .,. r- "'/"' J .J ' .) < "\ 

I"<"'/""~~ r >"'/ /../{ '"' Mz ~ ~- ~ "" ' .i /..1.._ V L<: \/\/ 

I -1 ::: r- f\ -1".,. / ''- " ..,~ ~ ' ( 

~--~"' I" r- "\ /v \ 

'" r- < >J (_ ___ .,.... 

/~\ 

(<~ 

...,.-:,.., ,... .,. rN 

l --f.<.~~ __ .,.,._......,.....,._~_,._., ... , 

QTf 

L 7 I'). t -.J L -.J A V I' l ). .,. "' A < 7 L v -J I 

" " ). .., ..l." 7 ,.. <., < / 

EXPLANATION 

l{ 8 ~ Spring sinter 

t=~:!l~~ Fluviatile and subaerial 

deposits 

i{ 

~ Silt, 

~ 

~ 

clayey silt, 

and fine sand 

~ 

~~~ ~os j 

~{ Fanglomerate 

~ ~ 

Q, Q;. 

Consolidated 

~ 

~ rocks, 

undifferentiated 

Contact 

Dashed where approximately l9cated, 

dotted where concealed or inferred 

--i.E.----····· u 

Fault, showing dip 

Dashed where approximately located 

(by Ferguson, Muller, and Roberts, 

1951); dotted where concealed and -

inferred in this report. U, upthrown 

side; D, downthrown side 

04 

Test boring or observation well 

and identification number 

'\2 

Spring and identification number 

._a 

Staff gage and identification letter 

--·4250 --

water-level contour and altitude, 

as of December 1960 

Contour iftterval 5 feet 

0 'f.! 1 2MILES 

FIGURE 4.1.-Generalized hydrogeologic map of a segment of the Humboldt River valley . 

.... " . 4 

>-

0:: 

< 

z 

0:: 

L1J 

t-

< 

;::) 

0 

>-

}

;;: ~ < .z -0::0:: 

t-ow 

0:: tLlJ < t- ;::) 

0 

} 

to 

I 

....... 

0 

0 

t?=:l 

0 

~ 

0 

0 

t-4 

0 

> 

~ 

Ul 

q 

~ 

-<l 

t?=:l 

~ 

~ 

t?=:l 

Ul 

t?=:l 

> 

~ 

0 

~ 

..... 

co 

0) 

~ 
).. 

ARTICLE 5 B-11 

tioned siliceous rock exposed in the flood plain north 

of well 5 suggests former hot-spring activity at least as 

far north ::ts that exposure. 

The media.l gravel unit of Lake Lahontan age was 

penetrated il) well 5 from the land surface to a depth 

of 83 feet. The pebbles and sand grains are almost completely coated with iron oxide. The temperature of 

the water in the well is 84° F. This is the only lest 

boring in the Hood plain in which thermal water was 

observed in the media,] gravel and in which the particles 

of the deposit are coated with iron oxide. The iron 

oxide coatings probably are related to the thermal water, 

and the thermal water is interpreted as being associated 

with the fault. · 

'Vell 3 penetrated poorly sorted coarse fanglomerate 

from the land surface to a depth of 32 feet. The 

stratmn beneath the fanglomerate is a dense plastic 

variegated cl~ty containing small fragments of amorphous silica. The occurrence, texture, ·and color of the 

clay, plus the relatively high temperature of the water 

in the well, also suggest hydrothermal activity-activity that probably is. related to the fault. 

'Vell 4 penetrated the upper silt and clay unit of" 

Lake Lahontan age from the land stn·face to a depth 

of 42 feet, fanglomerate from 42 to 75 feet, and basalt 

at a depth of 75 feet. The basalt is believed to be part 

of the upthrown side of the fault block bounded by the 

East Range fault, and it is tentatively correlated with 

the basalt exposed to the nortlnn~st across the I-Imnboldt River. 

The dissolved-solids content of the waters of springs 

1 and 2 and ".,.ells 3, 4, and 5 is about 4 to 5 times greater 

than the dissolved-solids content of the waters of the 

other wells and of the water of the Humboldt River. 

Also, the chemical character of the wa.ters of springs 

1 and 2 and wells 8 ~1nd 4 differs markedly from the 

chemica] character of the other wa,ters in the area.. The 

waters associated with the fault a.re sodium bicarbonate 

waters, whereas the other waters of the study area are 

mixed types. 

On the basis of the aforementioned hydrogeologic 

evidence, it is postulated that the East Range fault extends at least as far northward as shown in figure 4.1. 

It may extend northward across the Humboldt River, 

but this is uncertain. 

REFERENCE 

Ferguson, H. C., Muller, S. W., and Roberts, R. .J., 1951, Geology 

of the Winnemucca quadrangle, Nevada: U.S. Geol. Survey 

Geol. Quad. Map GQ-11. 

STRATIGRAPHY 

5. OLD METAVOLCANIC ROCKS OF THE BIG CREEK AREA, CENTRAL IDAHO 

By B. F. LEONARD, Denver, Colo. 

A varied sequence of old metavolcanic rocks is part 

of n. hu·ge roof pendant in the Idaho batholith at Big 

Creek, Valley County, Idaho. Big Creek, at lat 

45°07%' N., long 115°19112' vV., is near the middle of 

the exposed batholith. The metavolcanics are mainly 

dark-green amphibole- and mica-rich schists, but 

elongate-pebble breccias and conglomerates are conspicuous locally. Schistose quartz-feldspar rocks with 

relict feldspar phenocrysts are exposed in one area. 

The rocks are interpreted as flows, tuffs, and volcanic 

breccitl.s that were isoclinally folded and locally dist:upted long before the Idaho batholith was emplaced. 

They were in,truded at~d cut off by the batholith, and 

were reconstituted by heat and solutions from the 

629660-62-2 

cooling granitic mass. The age of the metavolcanic and 

associated metasedimentary rocks is presumably Precambrian or early Paleozoic. The word "old" is used 

here to distinguish these metavolcanics from the Casto 

Volcanics, which are also older than the batholith but 

are less deformed and of Permian ( ~) age. 

The main belt of old metavolcanic rocks, 5 miles long 

and 0.5 to 1 mile wide, trends northwest through Big 

Creek, parallel to a local southeastward projection of 

the batholith and separated from it by a_belt of metasedimentary rocks 0.5 mile wide: The metavolcanics 

belong m~inly to the epidote-amphibolite. facies, but 

rocks of amphibolite facies are exposed where the insulating layer of metasediments pinches out, bringing 
B-12 GEOLOGICAL SURVEY RESEARCH 19 6 2 

batholithic rocks directly against metavolcanics. To 

the northwest, the belt of metavolcanics loses its identity in a welter of Tertiary dikes that border the main 

contact of the batholith at this longitude. To the southeast, the metavolcanics pinch out or pass abruptly into 

massive metatuffs( n so poorly exposed that they cannot be distinguished in the field from the neighboring 

metasiltstones. A small mass of metavolcanic conglomerate in greenschist facies lies in a parallel syncline 3.5 

miles northeast of the main belt. The stratigraphic 

relations of this mass and of remnants farther northeast are uncertain. Fragments of elongate-pebble conglomerate and porphyrdblastic amphibole-pyroxene 

schist resembling rocks of the main belt are found as 

inclusions in the granitic rocks 20 miles south of Big 

Creek. Thus the old volcanic. rocks may once have extended for at least 20 miles across the present trend of 

the major fold systems of the metamorphic rocks. Some 

speculations on the former extent of these rocks are presented at the end of this article. 

A stratigraphic section across the best exposures of 

metavolcanics was measured by miniature theodolite 

. and stadia on the arete west of Placer Lake, 2.6 miles 

northwest of Big Creek. Three main meta volcanic 

units were recognized. From the top downward, the 

inferred sequence and present thickness of units is: 

metavolcanic breccia and conglomerate, 100-150 feet; 

hornblende schist and hornfels with relict. subophitic 

fabric, interlayered or interlensed with biotite-rich 

schist and hornfels, 240-330 feet; and porphyroblastic 

hornblende schist, 80-260 feet. The total thic·kness of 

the partial section is estimated to be 420-7 40 feet; the 

bottom of the meta vo~canics is not exposed here. Because of isoclinal folding and development of very 

large boudins, the true sequence may not be the one 

reported, and the estimates of thickness may be significant only as orders of magnitude. 

The upper part of the breccia unit is a strongly 

lineated rock having a fine gray matrix that contains 

abundant angular, elongate fragments of blastoporphyritic hornblende-rich hornfels, laminated biotiterich hornfels, quartz-feldspar hornfels, and' perhaps 

metasiltstone. The fragments range in length from a 

few millimeters to several centimeters. Some of the 

smaller ones are rounded. Their outlines are slightly 

blurred hy growth of new biotite. All the fragments 

except the metasiltstone are of metavolcanic rocks identical with those exposed elsewhere in the belt. The 

matrix is a mosaic of silt-size quartz and feldspar. It 

contains scattered euhedral plagioclase relics and 

roun.ded quartz grains with authigenic quartz overgrowths, and is partly replaced by biotite and magnetite. The rock is interpreted as a metamorphosed 

breccia rich in pyroclastic debris but with some fine 

particles derived from quartz-cemented sandstone 

("orthoquartzite''). The lower part of the breccia unit 

is a light- to dark-green medium-grained massive to 

schistose amphibole-rich rock containing sporadic elliptical pebbles of fine-grained quartzite and silty limestone. The quartzite and limestone are the same sort 

a.s those found in metasediments stratigraphically below the meta volcanics. Rare pebbles of dark-green finegrained hornblende-rich hornfels are present; probably 

these represent metamorphosed lava or tuff. The lower 

part of the breccia unit is interpreted as metamorphosed 

basaltic tuff, locally conglomeratic, perhaps with some 

lava. 

The middle unit, where hornblende rich, is feldspathic or calcareous. Some of the rock as a relict ophitic 

fabric, though it now consists of albite-oligoclase laths 

empedded in porphyroblastic blue-green hornblende and 

dark-green biotite. Schistose parts contain lenticles of 

granular sodic plagioclase in masses of hornblende and 

biotite. Sparse interlayers or lenses of very fine darkgreen biotite-rich hornfels and dark-gray silty laminated hornfels are present. Under the microscope, the 

silty hornfels shows relict euhedral plagioclaSe, and 

rounded quartz grains with authigenic quartz overgrowths. · Before metamorphism the rocks of this unit 

were mainly lavas, with subordinate volcanic siltstones. 

The lower unit contains little or no clastic debris. It 

is fine- to medium-grained massive to schistose amphibole-rich. rock consisting of dark-green to black hornblende porphyroblasts in a lighter green amphibole 

matrix. Granular sodic plagioclase is sparingly present. 

No relict fabric has been seen. 

Some epidote and sphene are present in ·the hornblende-rich rocks of all three units, ilmenite is usually 

an abundant accessory, and apatite is abundant locally. 

Blue-green chlorite is sparingly present in some rocks. 

A chemical analysis and mode of outwardly homogeneous dark-green hornblende schist from the middle 

unit are given in the table below. The analyzed sample 

contained a little vein calcite that is not present in the 

thin sections or in duplicate hand specimens. The rock 

was selected for analysis because it was abundant and 

seemed most nearly representative of the whole metavolcanic sequence. However, the analyzed rock seems to be 

of slightly higher metamorphic grade-perhaps lowermost amphi•bolite facies-than rocks in the measured 

section. The analyzed rock is high in Ti, as are other 

old mafic igneous rocks of the area. Except for Ti, 

the minor-element content of the rock does not differ 

significantly from that of several suites of metasedimentary rock from the various metamorphic zones. 

j 
~· 

ARTICLE 5 B-13 

Chemical data on other varieties of old metavolcanic 

rock ai·e not yet available. 

Oom.1JOsition ot hornblende schist 

[lricld No. L/53/617, lab. No. A 73; collected 0.25 mile southwest of 

Golcl Coin COl}PIJJ' prospect und 1.8 miles northwest of Big Creek 

R1wgcr Station, Big Creek quadrangle, Valley County, Idaho. Lois 

~e!"llmbull, nnalyst, 1955] 

CHI~MICAL AN AI-YSIS 

Weight perce11t 

810~------------------ 45.00 

Ti02 ----------------- • 3. 25 

Al~On ----------------- 11. 28 

l!""e~O:, ---------------- 3. 96 FeQ __________________ 9.71 

MnO ----------------- . 22 

~igO ----------------- 9.56 

CaO ----------------- 11. 77 

~a~o ----------------- 2.06 

1(20 ------------------ .57 

H~O+ --------------- 1. 80 

H20- ---------------- . 07 

PnOG ----------------- .43 

00:~ ------------------ . 43 

01 ------------------- •. 01 

F -------------------- .11 

s -------------------- .05 

Total ------------- 100.28 Less o_____________ . 07 

Total (corrected) ___ 100.21 

MODE 1 

Vohune percent 

Quartz~ -------------- =2. 7 

Plagioclase~ --------- =15. 1 

Epidote -------------- 1. 0 

Hornblende ----------- 62. 1 

Biotite --------------- 10. 0 

Sphene--------------- 1.4 

Apatite --------------- . 4 

Opaque minerals 3 _____ 5. 0 

Zircon ---------------- Tr. 

Chlorite -------------- 2. 3 

Total -------------- 100.0 

1 Average of 5 thin sections; 7,442 points counted. 2 Quartz plus plagioclase 17.8 percent in thin sections. Proportions 

estimated from grain counts In oils. Plagioclase, seldom twinned, has 

refractive indices Indicating a composition of An15- 35, averaging An25• 

8 Examined in 2 polished sections. Mostly ilmenite; some martltlzed 

mugnetite; a few specks of oxidized pyrite. 

'I'he rock is interpret~d as a metamorphosed basaltic 

lava or t_uff; the analyzed rock, apparently homogeneous, is similar to the matrix of neighboring rocks that 

contain several percent of quartzite and silty limestone 

pebbles. However, the analyzed rock is low in Si02 . 

and Al20s relative to CaO, or has relatively more CaO 

than known basaltic rocks of corresponding SiOz/ Al20 3 

ratio. Unmetamorphosed lavas or basaltic intrusive 

rocks of similar composition are indeed known, but they 

seem to be rather rare. Accordingly, an orthomagmatic 

process leading to enrichment in CaO seems unlikely 

for the hornblende schist. The difference in composition might be accounted for by several other processes, 

metamorphic or premetamorphic. 

Intense 1netamorphic differentiation in rocks of this 

gra~e is not an ~ttractive hypothesis: neighboring rocks 

retn1n mn.ny prunary features of igneous, pyroclastic, 

or epiclastic fabric; quartz veins along the margins 

of the belt of metavolcanics, and thus interpretable as 

venitic, show little evidence of the deformation that 

hns affected several silicified zones younger than the 

Idaho batholith; and metasedimentary rocks flanking 

tJ1e belt are not enriched in Ab03 • 

I£ Si02 and Al20 3 did not leave the hornblende schist, 

CaO may have entered as calcite, possibly during diagenesis of the tuffaceous rocks, or possibly during the 

earliest stage of metasomatic metamorphism, a change 

that was probably accompanied by introduction of H20 

and other volatiles. As the rock advanced through the 

greenschist facies to the epidote-amphibolite or lowermost amphibolite facies, C02 may have been expelled 

preferentially, leaving a homogenized rock relatively 

enriched in CaO, H20, F, Cl, and perhaps Ti02 and 

P205. 

The meta volcanics near Big Creek a.re the uppermost 

unit of a thick sequence of fine-graine9-, clastic, shallowwater rocks. This whole assemblage was mapp~d by 

Shenon and Ross (1936, fig. 2) as the Yellowjacket 

Formation, whicJ:l Ross ( 1934, p. 15 and pl. 1) had assigned to the Belt Series (Precambrian) . Identifiable 

fossils have not yet been found in this formation. Most 

of its least metamorphosed rocks are very similar to the 

Belt rocks of northern and eastern Idaho, and the inference of a Precambrian age is reasonable. However, 

lower Paleozoic rocks of similar composition and appearance are found southeast of Big Creek, in the 

Bay horse region described by Ross (1937). In the cen .. 

tral part of the Big Creek quadrangle, the meta volcanics 

overlie a carbonate unit which, where least metamorphosed, is fine-grained, thinly cross laminated quartzose limestone. Contacts between the carbonate unit 

and meta volcanics a.re now conformable, but this relation may be due to deformation, not to prima,ry deposi-

. tion. 

The meta volcanics a.re overlain-a.gain with apparent 

loca.l conformity-by a generally clean, dominantly 

white quartzite mapped by Shenon and Ross (1936) as 

the Hoodoo Quartzite, which Ross ( 1934, p. 15, 18-20; 

pl. 1) regarded as Precambrian. This quartzite has 

also failed to yield identifiable fossils. The evidence 

for a Precambrian age of the white quartzite in the 

Big Creek area is inconclusive; the quartzite may be 

Precambrian, Cambrian, or Ordovician, deposited unconformably on various units of the Y ellowj acket or 

thrust over them. 

Both the Y ellowj acket and Hoodoo of Shenon and 

Ross ( 1936) are cut by narrow mafic dikes of several 

sorts. These dikes, emplaced after isoclinal folding of 

the host rocks but before their reconstitution, have not 

been recognized within the metavolcanics, possibly because all the reconstituted mafic rocks look much alike 

in the field. 

The old metavolcanics are not to be confused with a 

younger assemblage of pre-batholith volcanic rocks in 

the area. The younger assemblage comprises flows, 

breccias, tuffs, welded tuffs, and volcanic grits that be-
B-14 . GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

long to the Casto Volcanics, a formation first described 

by Ross (1934, p. 28-35). In the Big Creek quadrangle, the Casto Volcanics lie unconformably on the .Hoodoo Quartzite of Shehon and Ross. The old meta volcanics are isoclinally folded and show greater internal 

deformation than the Casto. However, parts of the 

Casto have been intruded and thermally metamorphosed 

by the Idaho batholith to form hornfelses that resemble 

some of the old metavolcanics. The two sets of volcanics, as well as the post-batholith Challis Voleanics 

of Tertiary age, can be distinguished only by careful 

mapping. 

Old metavolcanic rocks of the sort. described here 

have not been reported from central Idaho, though 

Ross (1934, p. 27) mentioned tuffaceous rocks as one of 

several possible antecedents for "black schist" of indeterminate age near W oodt.ick Creek, Casto quadrangle. Lava flows are present in Belt roeks in northern Idaho and neighboring areas, but pyroclastic or 

· epiclastic volcanics seem to be rare: Johns ( 1961, p. 26) 

mentions one occurrence of basalt-pebble "agglomerate" 

overlying a flow of Purcell Basalt in northern Lincoln 

County, Mont.; Leech (1958; p. 8) notes that tuff is 

associated with andesitic lava at the top of the Kitchener-Siyeh Formation of the Purcell Series in the 

Fernie area, southeastern British Columbia. Far to 

the northwest and southeast of the Big Creek area, 

along the trend of regional structures in the old rocks, 

sequences that include both old metavolcanic rocks and 

coarse clastic deposits are found in northeastern Washington and in the Pocatello area,. southeastern Idaho. 

In the Metaline district, Washington, Park and Cannon (1943, p. 7-15) found that the thick, virtually 

unsorted, generally non volcanic ( ~) Shedroof Conglomerate graded upward into greenstone and green schist 

of the Leola Volcanics. Relict ophitic, diabasic, and 

amygdular( ~) textures, rare pillow structures, and 

tuffaceous fabric are preserved in some of the volcanics. 

Park and Cannon tentatively assigned both formations 

to the top of the Precambrian sequence in that area. 

The two units, each more than 5,000 feet thick, are unconformably(~) overlain by fine-grained phy1lites with 

subordinate carbonate rocks, quartzite, and grit (Monk 

Formation, tentatively placed at the bo,se of the Cambrian) and by the thick Gypsy Quartzite of Cambrian 

age. A similar sequence of conglomerate and overlying 

volcanics o"f ~recarribrian age, succeeded by quartzite 

of Cambrian age, has been recognized some distance 

south of the Metaline district by Bennett ( 1941), Campbell and Loofhourow (1957) ~ Weis (1959), and others. 

The correhitives of these. rocks in Canada have been 

discussed by Reesoi· (1957,·p.158-16.2'; 17'5), who interpreted part of the Precambrian sequence as eugeosynclinal. 

The meta volcanics near Pocatello are also greenstones. 

These metamorphosed lavas, tuffs, and volcanic breccias 

constitute the Bannock Volcanic Formation of Ludlum 

( 1942). According to Ludlum, a minimum thickness 

of 400 feet of Bannock is overlain by a thick sequence 

of mainly clastic rocks (Pocatello Formation) whose 

lower part contains coarse conglqmerates that he interpreted as tillites. According to Ludlum the Bannock, 

Pocatello, and overlying Blackrock Limestone are Precambrian, overlain unconformably by the very thick 

Brigham Quartzite of Cambrian age. Earlier workers 

assigned younger ages to some of these rocks. Others 

dispute the assignment of the nonfossiliferous lower 

strata of the Brigham to the Cambrian. 

In northeastern Utah, coarse clastic rocks of Precambrian and Cambrian age, locally overlain by quartzite of Cambrian age, have been interpreted as tillites 

by Blackwelder ( 1932) and <?thers. Mafic volcanic 

rocks seem to be sparse or absent from the scattered 

exposures of- these coarse clastic rocks. Dott (1961, 

fig. 4 and p. 1301-1303) recently reexamined some of 

the Utah "tillites" and concluded that their origin was 

uncertain. 

Precise correlation of metavolcanics at Big Creek 

with those to the northwest or southeast is not possible, 

and none should be inferred from this brief account. 

However, there is a "family resemblance" in the association of greenstones and coarse clastic deposits of 

relatively great age, overlain by thick, rather clean 

quartzites. The coarse clastic deposits are somewhat 

enigmatic in origin; they underlie the greenstone at 

Metaline but overlie it at Big Creek and Pocatello. 

The overlying quartzite is not conformable with the 

assemblage of greenstone. and conglomerate. Possibly 

the quartzite is late Precambrian in places; the upper 

parts are Cambrian near Metaline and Pocatello; coneeivably the quartzite is as young as Ordovician in 

central Idaho, if it is the correlative of the IGnnikinic. 

The Metaline and Big Creek areas of metavolcap.ics 

and coarse clastics coincide with the southwest margin 

of the Belt sea inferred by C. P. Ross ( 1961, personal 

communication) from his compilation of regional dat.a. 

(Because he regards the age assignment of the greenstone and conglomerate near Pocatello as uncertain, 

Ross does not inClude those rocks in the Belt.) . It is 

easy to speculate that the .eugeosyncline of Bel:t age 

postulated near the Canadi~n border by Reesor ( l9·57) 

and others extended southward and .southeastward, 

passing into a miogeosync~ine that contain~d relatively 

thin deposits of volcanic and epidastic volcanic rocks 

in the Big Creek area, and relatively thi1~ ·:~olcan~es 

,.J 
.. , 

I~ 

ARTICLE 6 B-15 

locally overlain by "tillite" in the Pocatello area. Such 

speculation is scarcely supported by the meager data 

on distribution of rocks having the family resemblance 

noted n.bove. I-Iowever, recognition of the resemblance 

may be useful in attacking some other problems of central Idaho geology. 

REFERENCES 

:Bennett, ,V. A. G., 1041, Preliminary report on magnesite deposits of Stevens County, 'Vashington: Washington State Dept. 

Conserv. and Devel., Div. Geology, Rept. Inv. 5, 25 p. 

Blackwelder, Eliot, 1932, An ancient glacial formation in Utah: 

Jour. Geology, v. 40, p. 289-304. 

Campbell, Ian, and Loofbourow, J. S., Jr., 1957, Preliminary 

geologic map nnd seetions of the magne~ite belt, Stevens 

County, Washington: U.S. Geol. Survey Mineral Inv. Field 

Studies Map MF-117. 

Dott, R. H., Jr., 1001, Squantum "tillite," Massachusetts-evidence of glaciation or subaqueous mass movements? : Geol. 

Soc. America Bull., v. 72, p. 128!}-1305. 

Johns, W. M., 1961, Progress ·report on geologic investigations 

in the Kootem:ti-l!,lathead area, northwest Montana, pt. 3, 

Northern Lincoln County: Montana Bur. Mines and Geology 

Bull. 23, 57 p. 

Leech, G. B., 1958, Fernie map-area, west half, British Oolumbia: 

Canada Geol. Survey Pruper 5&-10, 40 .p. 

Ludlum, J. C., 1942, Pre-Cambrian formations at Pocatello, 

Idaho: Jour. Geology, v. 50, p. 85-95 . 

Park, C. F., Jr., and Cannon, R. S., Jr., 1943, Geology and ore 

deposits of the Metaline quadrangle, Washington: U.S. Geol. 

Survey Prof. Paper 202, 81 p. 

Reesor, J. E., 1957, The Proterozoic of the Cord~llera in southeastern British Columbia and southwestern Alberta, in 

Gill, J. K, eel., The Proterozoic in Canada. Royal Soc. 

Canada Special Pub. 2, p. 150-177. 

Ross, C. P., 1934, Geology and ore deposits of the Oasto quadrangle, Idaho: U.S. Geol. Survey Bull. 854, 135 p. 

--1937, Geology and ore deposits of the Bayhorse region, 

Custer C01.mty, Idaho: U.S. Geol. Survey Bull. 877, 161 p. 

Shenon, P. J., and Ross, C. P., 1936, Geology and ore deposits 

near Edwardsburg and Thunder Mountain, Idaho: Idaho 

Bur. Mines and GeOlogy Pamph. 44, 45 p. 

Wei-s, P. L., 1959, Lower Cambrian and Precambrian rocks in 

northeastern ·washington [abs.] : Geol. Soc. America Bull., 

v. 70, p.1790. 

6. ANGULAR UNCONFORMITY BETWEEN MESOZOIC AND PALEOZOIC ROCKS IN THE NORTHERN SIERRA 

NEVADA, CALIFORNIA 

By L. D. CLARK, R. W. IMLAY, V. E. McMATH, and N. J. SILBERLING, 1\fenlo Park, Calif., 'Vashington, D.C .• 

Univ. of Oregon, Eugene, Oreg., Menlo Park, Calif. 

Work done in cooperation with the Oalifm"'nia Division of M·ines and Geology 

In the canyon of the North Fork of the American 

River about 5 miles south of Cisco in the northern 

Sierra Nevada, Calif., rocks of probable Silurian age 

are overlain with pronounced angular unconformity 

by rocks of Mesozoic age. The truncated Paleozoic 

strata are overlain by a sedimentary chert breccia 

which in turn is overlain conformably by limestone of 

Late Triassic ( ? ) age in the northern part of the area 

studied. Lower Jurassic beds of the Sailor Canyon 

Formation unconformably overlie the limestone in the 

northern part of the area and the chert breccia, in the 

southern part. The Paleozoic rocks are complexly 

folded and have a well-developed slaty cleavage; the 

Mesozoic rocks dip steeply but are little folded, and 

cleavage in them is obscure. The sharp contact between 

the Paleozoic rocks and the chert breccia is well exposed and is not faulted. The d.ihedral angle. between 

the bedding of the Paleozoic and Mesozoic rocks ranges 

:from. 0° to 90°. 

These relations provide evidence that the rocks of 

probable Silurian age were strongly folded, regionally 

metamorphosed to a low grade, and deeply eroded during later Paleozoic or Triassic time and that little 

folding occurred during latest Triassic (?) and earliest 

Jurassic time. Relations are much less clear elsewhere 

in northern California and westernmost Nevada, and 

proof of pre-Jurassic regional metamorphism and folding sufficient to cause vertical dips has been lacking. 

The unconformity separating Paleozoic and Mesozoic 

rocks was first recognized by Lindgren ( 1900), but new 

stratigraphic and structural information requires that 

his description of the relations be expanded and 

modified. 

CORRELATION AND AGE OF ROCKS BENEATH THE . UNCONFORMITY 

Paleozoic strata beneath the unconformity, exposed in 

the western part of the area (fig. 6.1), were included 

with the Blue Canyon Formation by Lindgren ( 1900). 
B-16 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

I 

I 

I 

I I 

I I 

_1!.·..!.~~----~------~------·-~-~--r-:~ T.15 N. I 

. 5 I 4 

I 

R.13 E. 

0 

f::K2~a Granitic rocks 

8fa 

Sailor Canyon Formation 

Js, siltstnne, graywacke, subordinate 

co:nglomerate, and limestone 

Jst, basal tuff unit 

Limestone ~ 

CJ 

Chert breccia 

Shoo Fly Formation 

Contact 

Dashed where approximately 

located 

~ 

Strike and dip of beds 

2 MILES 

EXPLANATION 

INDEX MAP SHOWING AREA OF THIS REPORT 

-.:::3:...:: 5:.._--139 ° 12'30" 

--fgo 

Strike of vertical beds 

EB 

Horizontal beds 

~ 

Strike and dip of cleavage 

t---g(j 

Strike of vertical cleavage 

-'-';{a) ~) Direction of tops of beds 

Determination based on (a) graded 

bedding, and (b) crossbedding. 

Plotted on strike with structure 

reading taken at point of observation 

4~ Minor fold 

Show{ng strike and dip of axial 

surface, and bearing and plunge 

of axis 

x® 

Fossil loc{llity 

. ®-

Locality referred to in text 

FIGURE 6.1.-Geologic map of an area including New York Canyon, Placer County, Calif. 

-
'\• 

ARTICLE 6 B-17 

The Blue Canyon Formation constitutes but one segment of a belt more than 100 miles long that is marked 

throughout by a distinctive and unusual assemblage of 

rocks. Of the three names that were used to designate 

various segments of this belt the name Shoo Fly Formation, applied by Diller (1892, p. 375·; 1908, p. 28) to the 

northern part, has priority and is here used for the entire belt (fig. 6.2). The name Blue Canyon Formation, 

which has been :applied to rocks only in the Colfax 

121° . 

EXPLANATION 

Shoo Fly Fonnation 

Taylorsville Formation 

oTruckee 

Blue Canyon Formation 

(Lindgren, 1900) 

Calaveras Formation Calaveras Formation 

(Lindgren and (Lindgren,l896) "'118 .. ) 

Placerville 0 

0 5 10 15 20 MILES 

Fxoun.E 6.2.-Map showing distribution of the Shoo Fly and 

Tnylorsville J!""ormntions. Other names applied to rocks of 

the Shoo J!""ly ]!""ormation in earlier studies Qf various 30-minute 

quadrangles are shown also. 

quadrangle (Lindgren, 1900), is here abandoned, and 

the name Calaveras Formation is restricted from the 

area shown as Shoo Fly Formation on figure 6.1. 

The Shoo Fly Formation is composed mostly of thinto thick-bedded light-colored graywacke or tuff or both, 

and grayish-green slate. Interbeaded with these are 

subordinate da.rk-gray slate, orthoquartzite, arkose, 

thin-bedded chert, andesitic( n pyroclastic rocks, thin 

limestone beds, conglomerate containing very well 

rounded pebbles of quartzite, and other rocks mentioned 

below in descriptions of local areas. The graywacke or 

tuff beds are commonly graded and consist of roundish 

quartz grains, and less commonly plagioclase and 

!{-feldspar, in a sericite matrix. 

Of four fossil localities previously reported to be 

in the Shoo Fly Formation,. one (Lindgren, 1900, p. 2) 

is in the Late Triassic ( ~) limestone of this report, and 

fossils at another. (Lindgren, 1900, p. 2) suggest only 

Paleozoic age. A fusulinid locality (Diller, 1908, p. 

2'3) is almost certainly separated from the Shoo Fly 

Formation by a fault, according to McMath 1 • Stromatoporoids suggesting Devonian or Mississippian age 

were fotmd near the contact between the Shoo Fly 

Formation and an overlying volcanic sequence, about 

midway between Taylorsville and the North Fork of 

the American River by Clark 2• Clark's description does 

not permit unequivocal assignment of the fossiliferous 

rocks to sither the Shoo Fly Formation or the volcanic 

sequence. 

A Silurian age for at least part of the Shoo Fly 

Formation, exposed west of Taylorsville (fig. 6.2) in 

the lower plate of a thrust fault, is suggested by correlating it with the fossiliferous Taylorsville Formation 

of Silurian age (Diller, 1908, p. 16), which is in the 

upper plate of the thrust 3 • Both the Shoo Fly and 

Taylorsville Formations are overlain with angular unconformity by a volcanic sequence having as its lowest 

three units an rinnamed rhyolite, the Taylor Meta-Andesite of l\1:ississippian age (Diller, 1908, p. 84), and 

the Peale Formation, also of Mississippian age. A 

similar relation between rocks here included with the 

Shoo Fly Formation and an overlying volcanic sequence 

is found about 25 miles southeast of Taylorsville (Durrell and Proctor, 1948, p. 171). 

West of Taylorsville, the lower and much the greater 

part of the Shoo Fly Formation consists of the quartzose sandstones or tuffs and slates that characterize 

the formation elsewhere. An overlying unit of the Shoo 

Fly Formation, and the equivalent Taylorsville Forma1 1\IcM:ath, V. E., 1958, Geology of the Taylorsville, Plumas County, 

California: California Univ., Los Ang~es, Ph. D. thesis, p. 38. 2 Clark, S. G., 1930, The Milton Formation of the Sierra Nevada of 

California : California Univ., Berkeley, Ph. D. thesis, p. 72. 

a McMath, ibid., p. 27, 167. 
B-18 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

tion above a fault that truncates its lower part, are each 

about 2,000 feet thick. They consist largely of black or 

greenish-gray obscurely laminated phyllite and slate, 

and thin beds, commonly graded, of feldspathic, possibly tuffaceous, graywacke. In the Shoo Fly Formation this unit is overlain by about 3,000 feet of andesitic 

greenstone, mostly derived from lava, and subordinate 

interlayered chert. 

DESCRIPTION OF AREA 

Within the area studied (fig. 6.1), the most abundant 

rocks in the Shoo Fly Formation are thin-bedded darkgray slate and siltstone that is in part pyritic and in 

part quartzose, thin-bedded chert, and fine-grained 

thin-bedded quartz-rich graywacke or rhyolitic tuff. 

Medium-grained arkose containing both plagioclase and 

K-feldspar is exposed on theN orth Fork of the American River. Conglomerate consisting of well-rounded 

quartz and quartzite pebbles is sparse. Some beds of 

coarse sandstone and fine conglomerate composed of 

angular fragments of chert are interbedded with siltstone and chert on the ridge north of map locaJity 4 

(fig. 6.1). Slaty cleavage is prominent in the originally 

argillaceous rocks, but original textures in the rocks 

of sand size and larger are well preserved, and in most 

. places the rocks are little sheared. Because rocks of the 

Shoo Fly Formation within the area of figure 6.1 have 

not been correlated with a specific part of the section 

in the Taylorsville area, they are designated Silurian(?). 

The Shoo Fly Formation is unconformably overlain 

by a coarse, nonbedded, poorly sorted chert breccia that 

locally attains a thickness of 75 feet or more. The 

breccia separates the Shoo Fly Formation to the southwest from fossiliferous Mesozoic rocks to the northeast, 

is structurally concordant with the Mesozoic rocks, and 

is considered Mesozoic in age. The composition and 

texture of the breccia vary along strike, but chert 

pebbles of various colors are everywhere the most 

abundant. Fragments of thin-bedded dark-gray slate 

and fine-grained graywacke or silicic tuff derived from 

the Shoo Fly Formation are common locally. Finegrained dioritic or quartz monzonitic rocks are common 

in the breccia near the north side of the rna p area. 

Sparse pebbles of mica schist were found at locality 4. 

The matrix consists of sand- and granule-sized grains 

of chert. Commonly the largest pebbles in the breccia 

are about 4 inches in diameter, but near the north edge 

of the area, scattered blocks as much as 20 inches long 

occur in the breccia. At localit-y 4 and on the crest of 

the ridge to the north, outcrop areas of the Shoo Fly 

Formation more than 20 feet long and 5 feet wide are 

surrounded by chert breccia. Such a pattern could resuit either from deposition of the breccia on a very 

irregular erosion surface or from incorporation of detached blocks of the Shoo Fly in the breccia. 

The contact between the chert breccia and the underlying Shoo Fly Formation is a nearly straight line at 

map scale, but in outcrops the contact surface has a 

relief of several feet. Where well exposed at localities 

2 and 4, the contact alternately follows bedding of. the 

Shoo Fly Formation and fracture surfaces that cut 

across the bedding. Rocks of the Shoo Fly Formation 

in contact with the chert breccia are: At locality 1, thinbedded chert; at 2 and 4, thin-bedded black slate; and 

at· 3 and 5, medium- and fine-grained graywacke or 

silicic tuff. 

North of the North Fork of the American River the 

chert breccia is conformably overlain by limestone of 

Late Triassic ( ~) age. In New York Canyon the breccia 

is overlain by the Sailor Canyon Formation of late 

Early Jurassic age. The chert breccia is of probable 

Triassic age. 

The limestone that overlies the chert breccia is about 

400 feet thick at the crest of the spur north of locality 

4. It is absent in New York Canyon, but is possibly· 

concealed on the south side of the canyon of the North 

Fork of the American River. The lower part of the 

limestone unit consists of alternating layers of thinbedded argillaceous gray limestone that weathers reddish brown, and thin- to medium-bedded gray limestone 

that weathers very light gray. Well-rounded granules 

or angular fragments of chert characterize some of 

these beds. The middle part consists of less argillaceotis 

limestone beds that form bold cliffs, and the upper part 

consists of thin interbeds of light-gray limestone and 

light-greenish-gray very fine grained pyritic sandstone 

probably derived from silicic tuff. 

A Late Triassic(~) age for the limestone is based 

mainly on the occurrence at locality 10 (USGS Mes. 

loc. M1167) of numerous spherical objects with the 

surficial and internal structure of H eterastridium, a 

supposed hydrozoan coelenterate that is widely distributed in deposits of Norian (late Late Triassic) age. 

Howev~r, in view of the doubtful biologic affinities and 

unknown evolutionary history of this organism, the 

age must be considered provisional. A post-Paleozoic 

age for the limestone is corroborated by the presence of 

poorly preserved ·scleractinian corals, large cidarid 

echinoid spines, and Pentaorinus-like crinoid columnals 

with petaloid crenulations on the articulating surfaces. 

· The Sailor Canyon Formation, occupying the eastern 

part of the map area, overlies the limestone unit in the 

northern part of the area and the chert breccia in the 

southern part. It is at least 10,000 feet thick and consists largely of graywacke, tuff of intermediate compo-

• 
~· 

ARTICLE 7 B-19 

sition, and dark-gray siltstone. The lowermost unit 

here included in the Sailor Canyon Formation consists 

of sparsely bedded, probably andesitic, tuff about 500 

to 700 feet thick. It weathers light gray green and 

ranges in texture from very fine grained tuff to lapilli 

tuff. 

The base of the Sailor Canyon Formation is well 

exposed in New York Canyon (fig. 6.1, loc. 2), where 

the tuff unit rests on the chert breccia along an irregular 

surface having a locnl relief of about 10 feet. Here the 

tuff unit contains n. 4-foot. layer of ehert breccia nbout 

20 feet nbove its base. The absence of the Upper Triassic( n limestone and the relief of the upper breccia 

surface ~tre interpreted as evidence of an erosional unconformity nt the base of the Sailor Canyon }formation, 

although very little Jurassic time can be represented 

by the unconformity. ' 

The age of the Sailor Canyon Formation, determined 

by ammonites, includes most of the Early Jurassic and 

some of the Middle Jurassic. About 1,000 feet above 

its base (fig. 6.1, loc. 6; USGS Mes. loc. 28403) 

O?•twilobioe'ras of middle Early Jurassic (late Sinemurian to early Pliensbachian) age was found. About 

2,000 feet above the base of the formation (fig. 6.1, locs. 

7, 8, and 9; USGS Mes. locs. 28396, 28391, 28395, respectively) Zugodaotyliooeras, Daotyliooera8, Orthildaites, Hildaites, and P?·otogram;nwce·ra,;? of late Early 

J u~·assic (early Toarcian) age were found. 

STRUCTURE 

The. Shoo Fly Formation is com.plexly folded, but 

nen,r the North Fork of the American River the gross 

strike :is easterly and the gross dip is northerly. Open to 

tightly cmnpressed folds range in amplitude from a few 

feet to n1any hundreds of feet. Slaty cleavage that is 

especially marked in the thin-bedded siltstones of the 

Shoo Fly Formation strikes northwest and dips steeply 

southwest or is vertical. The Mesozoic rocks are much 

less intricately folded; the trace of bedding on wellexposed canyon walls is nearly straight, and beds strike 

about N. 25° W. and dip northeast or are vertical. 

Cleavage is weakly developed in the Sailor Canyon 

Formation. The angle between bedding in the Shoo 

Fly and bedding in the Mesozoic rocks ranges from a 

few degrees to nearly 90°, owing to the earlier folding 

of the Shoo Fly Formation. Large dihedral angles are 

formed both where bedding in the .Shoo Fly Formation 

is nearly horizontal and where it is nearly vertical. 

REFERENCES 

Diller, J. S., 1892, Geology of the Taylorsville region of California: Geol. Soc. America BUill., v. 3, p. 370--394. 

--1895, Descr-iption of the Lassen Peak sheet [ Oalifornia] : 

U.S. Geol. Survey Geol. Atlas, Folio 15. 

--1908, Geology of the Taylorsville region, California: U.S. 

Geol. Survey Bull. 353, 128 p. 

Durrell, Cordell, and Proctor, P. D., 1948, Iron-ore deposits near 

Lake Hawley and Spencer Lakes, Sierra County, California, 

in Iron resources of OaHfornia: California Div. Mines Bull. 

129, pt. L, p. 165-192. 

Lindgren, Waldemar, 1896, Description of the gold belt; description of the Pyramid Peak quadrangle [California] : U.S. 

Geol. Survey Geol. Atlas, Folio 31,8 p. 

--1900, Description of ttlhe Col.fax quadrangle [California] : 

U.S. Geol. Survey Geol. Atlas, Folio66, 10 p. 

Lindgren, Waldemar, and Turner, H. W., 1894, Description of 

the gold lbelt; descri-ption of the Placerville sheet [ California] : U.S. Geol. Survey Geol. Atlas, Folio3. 

Turner, H. W., 1897, Description of the gold belt; description of 

the Downiev·Hle quadrangle [California]: U.S. Geol. Survey 

Geol. Atlas, Folio 37, 8 p. 

--1898, Description of the gold belt; description of the Bidwell Bar quadrangle [California] : U.S. Geol. Surv·ey Geol. 

Atlas, Folio 53, 6 p. 

7. MESOZOIC AGE OF METAMORPHIC ROCKS IN THE KINGS RIVER AREA, SOUTHERN SIERRA 

NEVADA, CALIFORNIA 

By JAMES G. MooRE and FRANKLIN C. DoDGE, Menlo Park, Calif. 

Fossils of Triassic or Jurassic age have been found in 

a large pendant near the confluence of the Middle and 

South Forks of the ICings River, in the southern Sierra 

Nevada, Calif. This pendant, here called the Boyden 

Cave .pendant after the cave of that name,. consists 

chiefly of metamorphosed sedimentary strata. It is one 

of a group of metamorphic remnants of similar lithology that are strung out through the dominantly 

granitic terrane of the Sierra Nevada for a distance of 

more than 70 miles. They extend from near Shaver 

Lake (J(rauskopf, 1953) in the San Joaquin drainage 

to Mineral King in the J(aweah and Kern River drain-
B-20 GEOLOGICAL SURVEY RESEARCH 19 6 2 

ages (Ross, 1958; Knopf and Thelen, 1905) and are 

composed of arkosic sandstone, argillite, marble (in 

part dolomitic), and only minor volcanic material. 

Figure 7.1 is a geologic reconnaissance map of part of 

the Boyden Cave pendant. 

The Boyden Cave pendant is well exposed along State 

Highway 180, 67 road miles east of Fresno. It trends 

a~out N. 20° W. and is 3 miles wide and more than 6 

Granitic 

~ 

~ 

rocks 

0 

---? 

2 3 

EXPLANATION 

m 

Arkosic 

sandstone 

85 ___J,_ 

~ Marble 

Con-tact, queried 

where uncertain 

Strike and dip 

of beds 

4 MILES 

Siltstone 

~0 

Strike of 

vertical be.ds 

FIGURE 7.1.-Reconnaissance geologic ma'p of an area near the 

junction of the Middle and South l!""'orks of the Kings River, 

southern Sierra Nevada, Calif. Circled numbers are fossil 

localities described in the table. Most of the map west of 

long.l18°51.5' W. is ·after Krauskopf (1953). 

miles long. Neither end has been mapped; northward 

it may be continuous with a pendant mapped by l{rauskopf (1953), 3 miles north of the junction of the forks 

of the Kings River. The intervening terrain on the 

7,000-foot-high north wall of the Middle Fork canyon 

has not been mapped. 

The bedding is steep or vertical in most places; therefore the horizontal width of the lithologic units 

represents their approximate thickness. Accurate 

measurement of stratigraphic thickness is not practicable because the rocks are metamorphosed and strongly 

deformed. The average maximum width of the pendant 

is 14,000 feet. The major units from west to east are: 

an arkosic sandstone unit, a ma.rble unit, and a siltstone unit. 

A rkosw sandstone ·unit.-The westernmost unit in the 

pendant forms a band about 9,000 feet wide and is composed of white or gray metamorphosed arkosic sandstone. Except for quartz, the most abundant mineral 

of the sandstone is K-feldspar, which averages about 13 

percent by volume of the rock. The western part of the 

sandstone unit is argillaceous and contains limy layers, 

but the middle and eastern parts lack these impurities. 

Where the sandstone is rather pure, it is commonly 

thick bedded and contains. cross-bedded laminations. 

Il). places these individual laminations, which are about 

1 inch thick, show graded bedding. Both the crossbeds .. 

and graded beds suggest that. the top of this. unit is to 

the west, and hence, that_ it is the· youngest unit of "the 

. pendant. A zone of shaly and limy ·sandstone ·.about a 

thousand feet wide forms the eastern part of .the unit. 

Marble unit.-East of the sandstone unit is a l;>a.nd of 

coarsely crystalline marble slightly more than 1,000 feet 

wide. Most of the carbonate rock is dolomite marble 

and contains less than 10 percent calcite, but Boyden 

Cave and many other small caves in the eastern side of 

this unit are in calCite marble containing only a little 

dolomite. 

Siltstone unit.-East of the marble is 4,000 feet of 

. thin-bedded siltstone, shale, and fine sandstone, much 

of which is metamorphosed to hornfels, slate, and phyllite. The eastern part contains thin-bedded layers of 

limestone. On the western side, about a quarter mile 

south of the highway, is a discontinuous layer several 

hundred feet thick of sedimentary breccia composed of 

fragments of thin-bedded sandstone, siltstone, and shale 

in an argillaceous matrix. Small-scale intricate folding 

is common in the siltstone unit, probably because it is 

composed of thin alternating competent and incompetent layers. In contrast, the other thicker bedded 

units sl:ww only broad open folds. The siltstone unit 

contains some volcanic rocks. Metamorphosed rhyolitic 

. ,-

·'I-
ARTICLE 8 B-21 

material is present in a thin strip of metamorphic rock 

projecting northward frmn the east side of the pendant 

and also near the south margin of the 1nn.p (fig. 7.1). 

Fossils have been collected frmn three localities in 

the siltstone unit of the Boyden Cave pendant. These 

fossils (see twble below) indicate a Mesozoic age, Triassic or Jurassic, for the si1tstone unit and proha:bly for 

all the rocks of the Boyden Cave pendant. 

Fossils from the Boyden Cave pendant, southern Sierra Nevada, Calif. 

No. on fig. 7.1 J .. ocallty Fossils Age Identified byL _ _ _ _ East side of Boulder Creek, 100 yards upstream 

from trail bridge; near center of sec. 10, T. 13 

s., n. 29 K 

Shell impression_____ Post-Precambrian __ _ R. J. Ross, Jr. (written 

commun., May 23, 

1961). 

2_ _ _ _ _ N en,r ridge crest, 100 yards east of Boulder 

Creek; close to center of sec. 10, T. 13 S., R. 

29 E. 

Pentacrinus sp____ _ _ _ Early Triassic to 

Late Jurassic. 

Porter M. Kier (written 

commun., July 14, 

1961). 

3_ _ _ _ _ 200-pound boulder in bed of South Fork of Kings 

River, 200 feet downstream from highway 

bridge across river; SWH sec. 3, T. 13 S., R. 

29 K Lithology of boulder indicates it 

originated less than ~'2 mile upstream. 

Ammonite(?) _______ Mesozoic(?) _______ _ N. J. Silber ling (written 

commun., Aug. 15, 

1961). 

The fossils of Triassic or Jurassic age found in the 

Boyden c~we pendant suggest that the rocks in the 70-

mile-long belt of lithologically similar roof pendants· 

n,re all of pre-Cretaceous ~1esozoic rather than Paleozoic age. Fossils of Late Triassic age previously reported from the Mineral ICing pendant n.t the south end 

of the belt (Durrell, 1940, p. 17) strongly support this 

view. Enst of this belt of pendants of sedimentary 

rocks is a more extensive belt characterized by predominantly volc~tnic material which has yielded Early J urnssic fossils (Rinehart, Ross, and I:Iuber, 1959). The 

strat.igraphic relationship between the rocks of these 

two belts of pendants is unknown; the two lithologies 

.may be of different ~\ge or different facies of the sani.e 

nge. 

REFERENCES 

Durrell, Cordell, 1940, Metamorphism in the southern Sierra 

Nevada, northeast of Visalia, California: California Univ. 

Pub. Geol. Sci., v. 25, no. 1, p. 1-118. 

Knopf, A., and Thelen, P., 1905, Sketch of the geology of the 

Mineral King District: California Univ. Pub., Dept. Ge.ology, 

v. 4, p. 227-262. 

Krauskopf, K. B., 1953, Tungsten deposits of Madera, Fresno, 

and Tulare Counties, California: California Div. Mines 

Spec. Rept. 35, 83 p. 

Rinehart, C. D., Ross, D. C., and Huber, N. K., 1959, Paleozoic 

and Mesozoic fossils in 'a thick stratigraphic section in the 

eastern Sierra Nevada, California: Geol. Soc. America 

Bull., v. 70, p. 941-946. 

Ross, D. C., 1958, Igneous and metamorphic rocks of parts of 

Sequoia and Kings Canyon National Parks, California:' 

California .Div. Mines Spec. Rept. 53, 24 p. 

8. RED BIRD SILTY MEMBER OF THE PIERRE SHALE, A NEW STRATIGRAPHIC UNIT 

By JAMES R. GILL and WILLIAM A. CoBBAN, Denver, Colo. 

The IUtnle Red Bird Silty Member of the Pierre Shale 

is given herein to a 200- to 725-foot unit of gray 1narine 

silty shale that crops out along the fla.nks of the Black 

J[il~s uplift :in eastern 'Vymning, southeastern Montana, 

and western South Dakota. The name is derived from 

the Red Bird store in the NE'% sec. 27, T. 38 N., R. 62 

W., Niobrltra County, Wyo. (fig. 8.1). 

The Red Bird Member was recorded originally as a 

"sandy shale member" (Cobban, 1951, p. 817). Later 

the outcrops on the north flank of the Black Hills uplift were briefly described as 200 feet of gra.y silty to 

sandy shale that contains iron-stained calcareous septarian concretions (Cobban, 1952, p. 87). In subsequent papers the unit has been referred to as the "un-: 
B-22 

PORCUPINE DOME 

Bearpaw Shale 

Judith River 

Formation 

Claggett Shale 

Q) 

-ro 

.s:: 

en 

>. 

"0 

0 

(..) 

Q) 

-ro 

.s:: 

en 

~ ..... 

Q) 

a: 

Unnamed 

shale member 

Hygiene 

Sandstone 

Member 

Unnamed 

shale member 

GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

\-•. =~~A--.\ -:~:T:-·\, I DAKOTA 

\ . PORCUPINEX 1 

·"'' ~~M-E-~-SOUT~ ~~) WHEELER 1 BRIDGE 

' sALT cR:;: ~-;;BxC==~ _ ~~ • WYOMING r L ~ NEBRASKA ' 

- -~ BOUL;E-R X • ----~ 

: COLORADO ' 

N 

1 

l_ ____ ___; 

BRIDGE Q) 

DeGrey Member -ro 

.s:: Crow Creek Member en Gregory Member Q) 

..... 

..... Sharon Springs Q) 

Member a: 

R.62 W. 

T. 

38 

N. 

GEOLOGIC MAP, RED BIRD AREA, NIOBRARA COUNTY, WYOMING 

FIGURE 8.1.-Location of the type section of the Red Bird Silty Member, Pierre Shale, Niobrara County, 'Vyo., and 

correlation with equivalent rocks in Wyoming, Montana, South Dakota, and Colorado. 

~ 

... 

··~ 
ARTICLE 8 B-23 

named silty member" (Cobban, 1958a, p. 663, 1958b, p. 

11(); Robinson, Mapel, and Cobban, 1959, p. 108; Scott 

and Cobban, 1959, p. 129; Tourtelot, Schultz, and Gill, 

1960, p. B447, B448; Gill and Cobban, 1961, p. D190). 

The Red Bird Member consists of soft silty shale 

tlutt weathers light to medium gray and contains 

numerous limestone concretions that weather light gray, 

yellowish gra,y, grayish orange, dark yellowish orange, 

and light brown to moderate yellowish brown and orange brown. The concretions are ordinarily 1 to 2 feet 

in diameter and 6 to 12 inches thick. Some are septarian, with thin veins of pale-yellow calcite. Very 

closely spaced concretions form conspicuous ridges in 

places. 

The Red Bird rests conformably on the very dark 

colored Mitten Black Shale Member and is conformably 

overlain by nn unna1ned dark-gray shale member. The 

Red Bird commonly forms a light to medium gray 

grass-covered outcrop belt between the adjoining darker 

and more poorly vegetated members of the Pierre Shale. 

Fossil mollusks are common throughout the Red Bird 

Member. In the type section near Red Bird the lower 

322 feet of the member is characterized by an undescribed species of Baculites that has a strongly ribbed 

venter. The next 343 feet is featured by Baculites 

g'regO'I·yensis Cobban, and the upper 60 feet is marked 

by B aculites scotti Cobban. 

The Red Bird Member was deposited marginal to 

nearshore marine sandstones that form the eastern edges 

of the Judith River Formation of Montana and the 

Pn,rkman Sandstone Member of the Mesaverde Formation of Wyoming (fig. 8.1). East of the Black Hills 

the Red Bird becomes less silty and is replaced by the 

calcareous Crow Creek and partly calcareous Gregory 

Members of the Pierre Shale. The name Red Bird 

Silty Member can be applied to a 150-mile-wide northtrending belt of rocks that lies east of the recognizable 

limits of the :Hygiene Sandstone Member of the Pierre 

Shale in Colorado, the Parkman Sandstone Member 

of the Mesaverde Formation in Wyoming, and the Judith River Formation in Montana, and west of the 

recognized limits of the Crow Creek and Gregory Members of the Pierre Shale in central South pakota (Gill 

and Cobban, 1961, .fig. 352.3B). 

The Red Bird ranges from 690 to 745 feet in thickness in the type area and is 725 feet thick in the type 

section. The following section, measured with a Sacob 

staff in the NW1,4SW% sec. 13 and NE:%SE% sec. 14, 

T. 38 N., R. 62 W., Niobrara County, Wyo., is desigmtted the type section. At this locality all of the Red 

Bird Member is silty. Bed 1 rests on the Mitten Black 

Shale Member and bed 15 is overlain by an unnamed 

dark shale member of the Pierre Shale. The Red.Bird 

dips 45°-60° NW. off the Old Woman anticline. 

Pierre Shale : 

Red Bird Silty Member: 

15. Shale; weathers light gray ; contains small limestone concretions at top and larger very closely 

spaced limestone concretions at base that form Feet 

a conspicuous yellowish-brown ridge__________ 4 

14. Shale; weathers light gray____________________ 47 

13. Shale ; weathers medium gray ; contains at base 

and top conspicuous beds of limestone concretions that weather gray to yellowish brown__ 9 

12. Shale; weathers medium to light gray; contains 

very few limestone concretions______________ 47 

11. Shale ; contains closely spaced limestone concre- tions at base and top _______________________ . 3 

10. Shale ; weathers light gray ; contains inconspicuous light-brown limestone concretions________ 140 

9. Shale ; contains closely spaced limestone concretions that weather orange and brown________ 1 

8. Shale; weathers light to medium gray; contains 

inconspicuous limestone concretions__________ 53 

7. Shale ; contains very closely spaced limestone concretions that weather yellowish gray and form a ridge_____________________________________ 1 

6. Shale; weathers medium gray; contains scattered gray-weathering limestone concretions__ 86 

5. Shale; weathers light gray; contains highly fossiliferous limestone concretions that weather 

medium gray to yellowish brown____________ 30 

4. Shale; weathers light gray; contains inconspicuous beds of limestone concretions that weather 

yellowish gray to yellowish brown ____________ . 136 

3. Shale ; weathers light gray ; beds of brownweathering limestone concretions at base and 

top, and 56 and 82 ft below top, form ridges___ 121 

2. Shale ; lower 2 ft and upper 4.5 ft weather light 

gray, remainder weathers brown_____________ 21 

1. Shale; weathers medium gray; contains a conspicuous bed of brown-weathering limestone concretions at top and a few concretions lower in 

the unit____________________________________ 26 

Total thickness Red Bird Member-------- 725 

Texas Eastern Transmission . 1 Federal oil and gas 

test well located in the center SW%NW"% sec. 15, T. 

38 N., R. 62 W., Niobrara County, Wyo. (figs. 8.1, 8.2) 

started in essentially horizontal rocks of the Fox Hills 

Sandstone and reached the top of the Red Bird Silty 

Member of the Pierre Shale at a depth of about 1,790 

feet and the base of the unit at about 2,390 feet. A 

thickness of 600 feet is assigned to the unit in the 

subsurface. 

The Red Bird Member is characterized on the electric 

log by a sharp but variable increase in the resistivity 
B-24 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

"Texas Eastern Transmission 

1 Federal 

Center SWl/.tNWl/4 sec. 15, T. 38 N., R. 62 W. 

Spontaneous 

self·potential 

Niobrara County, Wyo. 

Elev. 3880 feet 

Q) 

CQ 

.r:. 

en 

Q) 

~ 

~ 

Q) 

a.. 

~ 

Q) 

..0' 

E 

Q) 

~ 

>. 

-

en 

"0 

~ 

·-m 

"0 

Q) 

0:: 

Q) 

c: (ij Q) Q)J::..C 

~~E 

~~~ ffi 

Depth 

(feet) 

curve 

FIGURE 8.2.-Electric log of the Red Bird Silty 

Member, Pierre Shale, from well near type 

locality, Niobrara County, W\yo. 

curve which contrasts markedly with the uniformly low 

resistivity curves for the overlying and underlying shale 

units (fig. 8.2). The spontaneous self-potential curve 

shows noticeable but less well defined changes. The 

unit can be rec~onized easily on electric logs throughout 

the Powder River basin, eastern Montana, and part of 

North Dakota, but it is difficult to trace the unit in the 

area to the east. . 

REFERENCES 

Qobban, W. A., 195i, New species .of Baculites from the Upper 

Cretaceous of Montana and South Dakota: Jour. Paleontology,v.25,no.6,p.817-821. 

--1952, Cretaceous rocks on the north flank of tJbe Black 

Hills uplift, in Billings Geol. Soc. Guidebook 3d Ann. Field 

Conf., Black Hills-Williston basin, 1952: p. 86-88. 

--1958a, Two new species of Baculites from the western 

interior region: J~ur. Paleontology, v. 32, no. 4, p. 660-665 . 

--1958b, Late Cretaceous fossil zones of the Powder River 

basin, Wyoming and Montana, in Wyoming Geol. Assoc. 

Guidebook 13th Ann. Field Conf., Powder River basin, 

1958: p.114-119. 

Gill, J. R., and Cobban, W. A., 1961, Stratigraphy of the lower 

and middle parts of the Pierre Shale in the northern Great 

Plains States: Art. 352 in U.S. Geol. Survey Prof. Paper 

424-D, p. Dl85--D191. 

Robinson, C. S., Mapel, W. J., and Cobban, W. A., 1959, Pierre 

Shale along w.estern and nofltbern flanks of Black Hills, 

Wyoming and Montana : Am. Assoc. Petroleum Geologists 

Bull., v. 43, no. 1, p. 101-123. 

Scott, G. R., and Cobban, W. A., 1959, So-caned Hygiene Gronp 

of northeastern Colorado, in Rocky Mtn. Assoc. GeologlsU; 

Guidebook 11th Ann. Field Conf., Washakie, Sand Wash, 

and Piceance Basins, 1959: p. 124-131. 

Tour.telot, H. A., Schultz, L. G., and Gill, J. R., 1960, Stratigraphic variaotions in mineralogy and chemica·l composition 

of tJhe Pierre shale in South Dakota and adjacent parts of 

North Dakota, Nebraska, Wyoming, and Montana: Art. 205 

in U.S. Geol. Survey Prof. Paper 400-B, p. B447-B452. 

9. NOTE ON POST-RUSTLER RED BEDS OF PERMIAN AGE OF SOUTHEAST NEW MEXICO AND WEST TEXAS 

By JAMES B. CooPER, Albuquerque, N. Mex. 

Work done in cooperation with U.S. Atomic Energy Commission 

Red beds in southeast New Mexico and west Texas 

generally range in thickness from 200 to 500 feet and 

directly overlie the Rustler Formation of Permian age. 

The age of the red beds has been in question since 

about 1935. Red beds directly overlying the Rustler 

Formation in the subsurface of Loving County, Tex., 

were described by Lang ( 1935, p. 264) and were named 

the Pierce Canyon Redbeds, of Permian age. Later 

Lang (1937, p. 876) placed them in the Triassic System. Adams ( 1935, p. 1021) also considered the red 

t 
,,.. 

ARTICLE 9 B-25 

beds directly overlying the Rustler farther east in Texas 

to be of Permian age, but Page and Adams (1938, p. 

1709) redefined the Triassic-Permian boundary and 

placed it at the top of the red-bed unit which they named 

Dewey Lake Redbeds. A description of the Dewey Lake 

Redbeds, from a subsurface section in Glasscock County, 

Tex., is contn,ined in Page and Ada.ms (1940, p. 63). 

The writer became n.ware of the disputed age of the 

red-bed unit during the prepn.ratjon of subsurface sections reln.tive to ground-wa,ter investigations at the 

Project Gnome site in Eddy County, N. Mex., on behalf 

of the ·u.S. Atomic Energy Commission. Ct~ttings from 

test wells were examined to determine if the red-!bed 

unit correlated with the "Pierce Canyon" of, Triassic 

n.ge or with the Dewey Lake of Permian age. 

Figure 9.1 shows the relations of the red beds directly 

11hove the Rustler Formation in Eddy County, N.Mex., 

to those in Loving County, Tex., and eastward into 

Glasscock County, Tex., and to the overlying and underlying rocks. Data used were obtn.ined by examination 

of cuttings from each well shown on the cross section. 

Well 7 is the type section of the "Pierce Canyon Redbeds" and well 11 is the type section of the Dewey Lake 

Redbeds. 

The red beds are com posed of pale-reddish-brown 

fine s~tndy siltstone and a few thin beds of reddishorange fine sandstone. The composition is remarkably 

uniform in texture and color. The beds generally are 

dotted with small round to subround green to gray reduction spots. Gypsum is the common cementing agent; 

light-colored mica is a common accessory mineral. 

The basal contact of the red beds with the underlying 

Rustler is nowhere exposed at the surface, hut the contact is clear and distinct in the subsurface. The change 

from red siltstone to the light-colored anhydrite and 

gypsum of the Permian evaporite sequence cannot be 

overlooked in an exa.mination of sample cuttings, or mistaken by drillers. The top of the anhydrite is ma.rked 

on radioactivity logs by a sharp decrease in natural 

radioactivity. 

The contact of the red beds with over lying formations 

of Triassic or younger age is difficu It to determine. It 

DELAWARE BASIN CENTRAL BASIN PLATFORM MIDLAND BASIN 

0 0 (.) 8 0 0 0 u 

;;< 0 0 u u ooU u u 0 0 ~ u u u ~ ~ u 

T ~ <((,!) p:: p:: z 0 ~ :><Z (.!) ~ ~ p:: p:: z u u < u ~- z ~ ~ 0 0 < ~ en >< < ~ E-<~ > ~ ~ E-< E-< ~ en ~ ~ 0 z z u u ~ ~ < ~ ~ ~ ::. ~ ~ ~ ~ ~ 

~ ~ ~ 

z (.!) 

Santa Rosa Sandstone 

3600' 

nta Rosa Sandstone Rocks of 

3200' 

2800' 

2400' 

2000' 

1600' 

1200' 

WELLS SHOWN ON SECTION 

1. USGS test hole 1 (Project Gnome) 

0 20 MILES 2. Continental Federal 1 W. J. Weaver 

LLL.LJ 3. Harrison 1 Rowley 

4. Ohio Oil Co. Federal 1 Sunshine Royalty 

5. El Cinco Products 1 Humble Madera 

6. J. E. Whitesides 1 J. E. Whitesides 

7. Pinal Dome 1 Means 

8. Carter Oil Co. & Pure Oil Co. 2C J. B. Walton 

9. Landreth Producing Corp. & Shell Oil Co. 1A J. L. Johnson 

10. Broderick & Calvert 1 Bryant 

11. R. R. Penn 1 Habenstreit 

INDEX MAP SHOWING LINE OF SECTION 

FrounE 9.1.-Geologic section showing relation of Dewey Lake Redbeds to "Pierce Canyon Redbeds," southeast New Mexico 

and west Texas. 
B-26 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

is not usually recognized by drillers. The contact is 

not always apparent from an examination of sample 

cuttings, although it is generally recognizable if the 

samples 'have been properly collected and prepared. 

As shown on figure 9.1, the red beds are overlain by the 

Tecovas Formation as far west as eastern Loving 

County, Tex.; northwest of these the red beds are overlain by the Santa Rosa Sandstone of Triassic age and 

the Ogallala Formation (Pliocene). 

The change from rocks of known Triassic age to red 

beds of Pet-mian or Triassic age is generally marked 

by a change from a dark purplish color to a dull reddish 

brown. Rocks of Triassic age generally contain fine 

angular sand gra.ins and much da.rk mica, 'vhich are uncommon in the red beds. Reduction spots are useful, in 

a general way, as a stratigraphic marker, although they 

are not limited to the red beds hut are found also in the 

overlying beds of Triassic age. However, the reduction 

spots are more abundant in the red beds, and when the 

spots are present in quantity the observer can search 

more closely for other diagnostic features of the red 

beds. 

Garza and Wesselman (1959, p. 18) report that in 

Winkler County, Tex., the top of the red beds generally 

is recognizable on gamma-ray and electric logs. The 

structural trough in Winkler County, shown on the 

cross section, was outlined by them from electric-log 

data. This trough. was formed by subsidence during 

removal by ground water of soluble salts in the underlying Permian rocks. The east edge of the- trough 

approximately overlies the buried Capitan reef, and 

the axis of the trough trends generally south, extending 

from Lea County, N.Mex., through the western part of 

Winkler County and southward into Ward County. 

The purpose of this paper is to point out that the red 

beds overlying the Rustler Formation in southeast New 

Mexico and the Dewey Lake Redbeds overlying the 

Rustler in west Texas appear to be a single lithologic 

and stratigraphic unit, and that, to the writer, the 

lithology, color, and apparently conformable relation 

with the Rustler Formation suggest that the red beds 

are of Permian age. In view of these relationships, 

only one name should be used for this unit. The name 

Dewey Lake Redbeds is well established in the literature and is used by industry for this unit in New 

Mexico as well as Texas, and no question has been 

raised as to its validity or age designation. Also, the 

age designations of Permian, Triassic, and Permian or 

Triassic given the red beds called "Pierce Canyon" in 

geologic literature have been confusing. Accordingly 

the name Dewey La.ke Redbeds is used herein for the 

post-Rustler red-bed-unit. 

REFERENCES 

Adams, J. E., 1935, Upper Permian stratigraphy of West Texas 

Permian Basin: Am. Assoc. Petroleum Geologists Bull., v. 

19, no. 7, p. 1010-1022, 2 figs. 

Garza, S., and Wesselman, J. B., 1959, Geology and groundwater resources of Winkler County, Texas: Texas Board of 

Water Engineers BUll. 5916, 200 p., 8 pls., 15 figs. 

I.ang, W. B., 1935, Upper Permian formations of Delaware basin 

of Texas and New Mexico: Am. Assoc. Petroleum Geologists 

Bull., v. 19, n<>. 2, p. 262-270, 7 figs. 

--1937, The Permi-an formations of the Pecos Valley of 

New Mexico and Texas: Am. Assoc. Petroleum Geologists 

Bull., v. 21, no. 7, p. 833-898, 29 figs. 

Page, L. R., and Adams, J. E., 1938, Stratigraphy, Eastern Midland Batsin, Texas [abs.] : Am. Assoc .. Petroleum Geologists 

Bull., v. 22, no. 1Z, p. 1709. 

--1940, Stratigraphy, Eastern Midland Basin, Texas : Am. 

Assoc. Petroleum Geologists Bull., v. 24, no. 1, p. 52-64, 

2 figs. 

10. VOLCANIC ROCKS OF OLIGOCENE AGE IN THE SOUTHERN PART OF THE MADISON RANGE, MONTANA 

AND IDAHO 

By WARREN HAMILTON and EsTELLA B. LEoPOLD, Denver, Colo. 

The south end of the Madison Range is composed of 

Oligocene tuffs and flows that overlie rocks ranging 

from middle ( ? ) Precambrian to Early Cretaceous in 

age and that are overlapped by Pliocene(?) and Pleistocene rhyolite tuffs of the surrounding YellowstoneSnake River volcanic province (fig. 10.1). This article 

is based upon reconnaissance made as part of the geologic study of the region of the Hebgen Lake earthquake of 1959. A summary of the volcanic geology has 

been published (Hamilton, 1960). 

The Oligocene rocks, exposed in the mountains south 

of Targhee Pass, make a bedded sequence about 1,000 

feet thick of rhyolite welded tuff and mafic alkaline 

lava. This part of the Madison Range is a fault block 

.. _ 
':-· 

.~ 

. .., 

' 

ARTICLE 10 B-27 

....., 

RANGE=:::.: 

~!~t.~;~~N~\~~~;Dt~')l~;~:;·i·, i1Yii'11111 111 

CENTENNIAL 

MOUNTAINS 

5 

Pr~\fertiary rocks 

'---~ 'o 

B~~-?» ~~,~~ o''\ 

0 5 10 MILES 

FIGUUE 10.1.-Geologi<: outline map of the south end of the Madison Range and Yicinity, I~aho, Montana, and Wyoming, 

showing distribution of volcanic rocks of Cenozoic age. Oligocene fossil flora were collected at locality marked 

by +, and chemically analylr.ed rock samples were collected at localities marked by X. Volcanic rocks of Cenozoic 

age are not shown in the Gravelly Range, Centennial Mountains, or Madison Valley. Stippled pattern indicates 

alluvium . 

in which the Oligocene volcanic rocks dip gently eastsoutheastward, complicated by minor faults and local 

folds. Exposures are poor owing to thick colluvium 

and dense forest. 

Welded rhyolite tuff forms about half the sequence. 

The tuff varies from glassy to thoroughly devitrified 

and contains abundant small phenocrysts of clear sanidine and a few phenocrysts of quartz and oligoclase; no 

biotite or hornblende was seen. Welding is generally 

dense a,nd secondary flowage apparent. The specimen 

nnn.lyzP,d chemically (see ta,ble, No. 3) is silicic, moderately nJuminous, and luts a moleculnr ratio of K 2 0 to 

Na,..!O of 3: 2, a little lower than that of Nockolds' (1954, 

p. 1012) average calc-alkaline rhyolite. Relative to 

Nockolds' average, this ~·hyolite tuff is low in both cal629660--62--3 

cium and magnesium. Relative to the amounts of some 

minor elements in rhyolite and dacite glass from many 

areas in the "\Vestern States (Coats, 1956), this sainple is 

intermediate in content of fluorine, lanthanum, lead, 

niobium; and tin; moderately high in zirconium; low in 

beryllium; and very low in boron. The chlorine content 

is high.· 

Flows of mafic alkaline rocks are interbedded with 

the rhyolite tuff. Near the top of the sequence, a distinctive flow of trachya.ndesite and another of leucite 

basanite, each about 150 feet thick, can be traced for 

several miles. Flows with the appearance of open-textlired basalt are present but were not studied petrographically. No intermediate rock of andesitic or 

dacitic composition was recognized. 
B-28 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

Chemical analyses of volcanic ror;ks of Oligocene age in the southern part of the Madison Range, Mont. 

[Major oxides determined by rapid colorimetric methods by Paul Elmore, Ivan Barlow, Samuel Botts, and Gillison Chloe, Washington, D.C., 1961. .Fluorine and chlorine 

determined by Vertie C. Smith, Denver, Colo., 1961. Other minor elements determined by semiquantitative spectrographic methods by Paul R. B!lmett, Denver, Colo., 

1961; values reported as midpoints of logarithmic-third divisions. All determinations are given in weight percent] 

MAJOR OXIDES 

1 2 3 1 

Si02------------ 48. 6 52. 6 75. 6 B _____ 0. 003 

Al20a----------- 10. 2 13. 9 12. 6 Ba ____ . 15 

Fe20a- _-------- 3. 4 6:6 1.0 Be ____ . 00015 

FeO _____ - ------ 5. 4 2. 0 . 76 Ce ____ <. 01 

MgO ___ - - - - - - - - 12. 4 5. 8 . 07 CL ___ . 02 

CaO ______ - _ - - - 7. 8 7. 9 . 59 Co ____ . 003 

N a20 ______ - _ - - - 2. 6 2. 3 3. 6 Cr ____ . 07 

K20----- - - - - - - - 2. 0 4. 4 5. 1 Cu ____ . 007 

H2o _____ ------- 5. 9 2. 7 . 36 F _____ . 05 

Ti 02 ___ ------- - . 70 . 76 . 12 Ga ____ . 0007 

P20s----------- . 76 . 62 . 02 La ____ <. 002 

MnO ____ ------- . 16 . 14 . 04 Mo ___ <. 0002 

TotaL _______ 99. 9 99. 7 99. 9 

1. Leucite basanite. Euhedral phenocrysts of leucite, augite, 

and s.ubordinate olivine comprise about half the rock, and 

are set in glass that is dark gray in hand specimen and 

pale green in thin section. Leucite occurs as 1-mm trapezohedra. Stubby prisms of augite (+2V=65°) as long as 

5 mm are greenish black in hand specimen and light green 

in thin section. Colorless olivine has 2V =90°. No phenocrysts ate altered o:r embayed. Magnetite is sparse. .The 

glass is clear and nondevitrified, except for small brown 

radially structured amygdules of an unidentified low-birefringent material with or without isotropic cores. Collected by forest road on west slope of hill 7890, SW~ sec. 

3, T. 14 S., R. 4 E. Field No. YS-17; lab. Nos. 158053 and 

H3308. 

2. Iddingsite-augite trachyandesite. Grayish-ref\ holocrystalline 

groundmass, consisting of andesine (Anw) laths, granules 

of alkali feldspar, augite, iddingsite, and magnetite, and 

The trachyandesite has a distinctive grayish-red holocrystalline groundmass of andesine and alkali feldspar, 

with subordinate augite and iddingsite, and is conspicuously studded with phenocrysts of greenish-black 

augite. Iddings ( 1895) coined the name "shoshonite" · 

for similar rocks in the Oligocene volcanic sequence of 

the Absaroka Range. There is no disseminated hematite; the red color is due to iddingsite, as is shown in 

the analysis (table, No. 2) by a high Fe.z03 :FeO r~tio. 

The leucite basanite is a dark-gray rock ·studded 

densely with large phenocrysts of augite and olivine 

and smaller ones of leucite, set in a matrix of dark 

glass. The glass wetithers to a brownish-yellow surface, 

against which the phenocrysts are conspicuous, but in 

fresh rock the glass is not devitrified. The phenocrysts 

are fresh, sharply euhedral, and show no embayment, 

corrosion, or reaction rims. This rock is identified as 

basanite, although no plagioclase is present, because of 

its chemical composition (table, No. 1); calculations 

suggest that plagioclase would have formed had the 

glass crystallized. Reic~tive to most leucite-bearing 

rocks, however, this specimen is low in aluminum and 

potassium. It is chemically similar to some of the lavas 

of Vesuvius. 

MINOR ELEMENTS 

2 3 1 2 3 

<O. 001 <O. 001 Nb ___ <O. 0005 <O. 0005 0. 003 . 15 . 07 Nd_ ~ _ <· 005 <. 005 . 007 . 00015 . 0003 Ni_ ___ . 015 . 003 <. 0002 <. 01 . 015 Pb ____ . 0007 . 0007 . 0015 . 01 . 13 Sc ____ . 003 . 003 <. 0005 . 003 <. oooz Sn ____ <. 0002 <. 0002 . 0007 . 03 . 00015 Sr_--- . 15 . 15 . 003 . 015 . 0007 v _____ . 015 . 03 <. 0005 . 10 . 08 y ----- . 0015 . 0015 . 007 . 0007 . 0015 Yb ____ . 00015 . 00015 . 0007 

<. 002 . 007 Zr_--- . 007 . 007 . 03 

<. 0002 . 0003 

interstitial clay ( ? ) , is studded with euhedral prisms, 2-7 

mm long, of greenish-black augite. There are fewer 

phenocrysts of normally zoned labradorite, and abundant 

pseudomorphs of red iddingsite after small phenocrysts and 

granules of olivine. Collected from bluffs above forest 

road, SE1,4 s.ec. 1, T. 14 S., R. 4 E. Field No. YS-12; lab. 

Nos. 158051 and H3306. 

3. Rhyolite welded tuff (dark-gray pitchstone in hand specimen). Abundant small phenocrysts of clear sanidine, and 

subordinate ones of oligoclase and high quartz, lie in brown 

glass formed of mashed shards that show conspicuous 

secondary flowage. The glass contains microlite needles of 

pyroxene ( ?) and rare granules of magnetite. The glass 

shows no devitrification except for sparse incipient spherulites. By forest road at altitude of 7,000 feet, SE% sec. 

2, T. 14 S., R. 4 E. Field No. YS-14; lab. Nos. 158052 and 

H3307. 

Like many mafic-alkaline rocks, the trachyandesite 

and the basanite have relatively large amounts of barium and strontium. They have a rather high fluorine 

content, but the amounts of other minor elements are· 

comparable to those in most basaltic rocks. 

Soft tuffaceous siltstone and a little gray to buff sandstone and mudstone are interbedded with rhyolite tuff 

in the lower part of the sequence near its north boundary. The sediments have an aggregate thickness of 

about 200 feet. Tuffaceous siltstone ·collected from a 

cut along a logging road 6 miles west of West Yell owstone, Mont. (fig. 10.1), in the SE% sec. 34, T. 13 S., 

R.. 4 E., at USGS Paleobotany Locality D-1430, yielded 

pollen as listed below according to genus and USGS 

code species : 

Gymnospermae 

Podocarpaceae 

cf. Podocarp1t8; V2S/sm-8, V2L/sm-12 (podocarpus) 

Pinaceae 

Abies cf. A. lasiocarpa Nuttall; V2L/p-1 (fir) 

cf. A. concolor (Gordon) Coopes; V2S/sm-4 

Picea, cf. P. engelmanni Engelmann ; V2Sjsm-5 

(Engelmann? spruce) 

A. 

l' 
... 

.,. 

ARTICLE 11 B-29 

P·intts Y2S/sm-10 (pine) 

Tsuga cf. T. rnertensiana (Bongard) Sargent; 

Tsng-1 (hemlock) 

Tnxodiaceae 

cf. Sequoia a/finis Lesquereaux; Tax-p--1 

(sequoia'?) 

Gnetncene 

Ephed·ra cf . . E. nevadensis Watso~·; Gn-7 (ephedra) 

.Angiospermae 

Gramineae, undetermined (grass) 

Snlica<.:eae 

cf. Sal·ix; 03-rt-13 (willow) 

Juglandaceae 

Oa·rya; P3-sm-40, P3-sm-14a (hickory) 

Pte·roca·rya; P5-sm-5, · P6-sm-:-2 ( lingnut) 

Betul11ceae 

JJ etttla; :P3-sm -12 (birch) 

A.l'IMts; P5-sm-1, P4-sm-3 (alder) 

cf. Ost1·ya; P3-sm-43 (hornbeam) 

Ulmf¥!ene 

Dlnws or Zel"ko·1:a.; P4-foss-1, P~foss-1 (elm) 

Aquifoliaceae 

Jle:c; C3P3-p-4 (holly) 

Rosacette ; 03-st-2 

Family and generic affinities not certain : 

cf. E'llcomon·ia,; 03-sm-18 

cf. Platanus; 03-r-21 (sycamore?) 

cf. Liq·ni(la?nbar ,· P3-sm-42 

cf. 'l.'·il·ia; BCP3-r-7 (linden?) 

Stcphanop01·opollenites; P5-sm-4 (a pollen-form 

genus) 

Four of the cerbtinly identified genera ( Oa1·ya, PteToca'rya, [llmtt8 or Zelh~ova, and /lex) do not now live in 

the region. The pollen species of Salix ( ~), Platantl8 ( ?) , 1',ilia (?), a.nd StephanoJJOT01Jollenites have 

been found in the 'Vestern States only in sediments of 

Oligocene age, including the Florissant Lake Beds of 

Colorado and the 'Vhite River Group of 'Vyoming. 

~1ost of the other plants are known from strata of both 

Oligocene and ~Eocene ages in the region, although 

several have not been found previously in the region 

in rocks of either age. An Oligocene age is probable, 

and a 1noist-temperate climate is indicated. 

Lapping onto the Oligocene and pre-Tertiary rocks of 

the southern part of the Madison Range a.re rhyolite 

tuffs of the Snake River-Yellowstone volcanic pt~ovince 

(fig. 10.1) of Pliocene and Qmtternary volcanism. The 

young rhyolite is genera1ly on low ground about the 

base of the mountains-porous Pleistocene rhyolite 

laps across the Madison R~1>nge frontal fault from the 

basin of Henrys Fork of the Snake River-although 

Pliocene(~) rhyolite has been considerably uplifted 

north of Targhee F ass. Constructional surfaces are 

preserved on large areas of these young rhyolites~ 

whereas they are lacking on· the Oligocene rocks. 

Alkaline ma.fic rocks are limited to the Oligocene sequence, but as some of the rhyolite of ·that sequence is 

similar to welded tuff of the Yellowstone volcanic 

province the two assemblages may have been confused 

in part. 

REFERENCES 

Coats, R. R., 1956, Relationship of uranium and other trace 

elements to post-Cretaceous vulcanism: U.S. Geol. Survey 

TEI-159, 66 p., issued ·by U.S. Atomic Energy Comm. Tech. 

Inf. Service, Oak Ridge, Tenn. 

Hamilton, Warren, 1000, Late Ceno7-oic tectonics and volcanism 

of the Yellowstone region, "\Vyo.ming, Montana, and Idaho, 

in Billings Geol. Soc. Guidebook 11th Ann. Field Conf., West 

Yellowstone-earthquake area, 1960: p. 92-105. 

Iddings, J. P., 1895, Absarokite-shoshonite-banakite series: 

Jour. Geology, v. 3, p. 935-959. 

Nockolds, S. R., 1954, Average chemical compositions of some 

igneous rocks: Geol. Soc. America Bull., v. 65, p. 1007-1032. 

11. RADIOCARBON DATES RELATING TO A WIDESPREAD VOLCANIC ASH DEPOSIT, EASTERN ALASKA 

By ARTHUR T. FERNALD, Washington, D.C. 

A conspicuous blanket of volcanic ash, first described 

by Schwatka (1885, p. 196) and Dawson (1889, p. 43b46b), covers a wide area in eastern Alaska and southern 

Yukon Territory. It generally occurs at or near the 

surfn.ce of the ground, ~ut in certain localities it has 

been buried by sever~tl feet of loess and organic material. 

The distribution and thickness of the ash have been 

m~tpped in detail by Bostock ( 1952, fig. 1). 

Capps (1916, p. 69-75, 81-83) estimated the age of 

the ash to be 1,400 years in the vVhite River valley, 

where it is overlain by 7 feet of peat. He based this 

estimate on a calculn.ted accumulation rate of 1 foot of 

peat in 200 years determined from the ages of trees, tts 

shown by their annual rings, growing on a constantly 

thickening moss mat. He had observed that the trees 

send out successively higher root branches as the permafrost table, which is related to the thickness of n1oss, 

rises. 

The 1,400-year age is remarkably close to radiocarbondated peat samples that indicate the ash fell between 
B-30 GEOLOGICAL SURVEY RESEARCH 19 6 2 

1,750 and 1,520 B.P. (Before' Present). The samples 

were collected from layered peat that overlies and 

underlies the ash in an exposure in the upper Tanana 

River valley. A pit dug in an interduue hollow within 

a stabilized dune field exposes, from top to bottom, (a) 

16 inches of peat with admixtures of silt, (b) 6 inches 

of white ash, (c) 2 inches of peat, and (d) gray-brown 

dune sand. The sample (I-276) 1 from the bottom 2 

inches of the upper peat bed is dated at 1,520+100 B.P. 

The sample (I-275) 1 from the lower bed has a date of 

1,750+ 110 B.P. 

Another radiocarbon-dated peat sample, collected 

from within the flood-plain deposits of the upper· 

Tanana River, gives a maximum age of 2,000+250 years 

B.P. for the ash fall. The cut bank exposes, from top 

to bottom, (a) 12 inches of layered peat, (b) 42 inches 

of bedded silt and fine sand with organic debris, (c) 30 

inches of white ash with thin beds of gray silt, and (d) 

6 inches of layered peat. The sample (W-978) 2 was 

cqllected from the middle part of the lower peat bed. 

The age of the ash provides an important reference 

point in the interpretation of the surficial geology of the 

upper Tanana River valley, particularly the flood-plain 

deposits. The ash is not present on or within the 

deposits of the slip-off slopes of the Tanana River 

but it is preserut on all low terraces. It has been re: 

worked into the deposits of parts of the flood plain 

that are intermediate between the slip-off slopes and the 

low terraces, as in the cut bank described above. 

REFERENCES 

Bostock, H. S., 1952, Geology of northwest Shakwak valley, 

Yukon Territory: Canada Geol. Survey Mem. 267, 54 p. 

Capps, S. R., 1916, The Chisana-White River District, Alaska: 

U.S. Geol. Survey Bull. 630, 130 p. 

Dawson, G. M., 1889, Report on an exploration in the Yukon 

District, N. W. T., and adjacent northern portion of British 

Columbia: Canada Geol. Survey Ann. Rept., v. 3, pt. 1, 

rept. B ( 1887-88) , 277 p. 

Schwatka, Frederick, 1885, Along Alaska's great river: New 

York, Cassell & Co., 360 p. 

1 Dat~d by Isotope~, Inc., Westwood, N.J. 2 Dated by U.S. Geological Survey Radiocarbon Laboratory. 

SEDIMENTATION AND SEDIMENTARY PE'/'ROLOGY 

12. ORIGIN OF SPHERULITIC PHOSPHATE NODULES IN BASAL COLORADO SHALE, BEARPAW 

MOUNTAINS, MONTANA 

By W. T. PEcoRA, B. C. HEARN, ,JR., and CHARLES MILTON, Washington, D.C. 

STRATIGRAPHY 

Spherulitic phosphate nodules occur in the Fall River 

Sandstone Member at the base of the marine Colorado 

Shale in the Bearpaw Mountains, north-central Montana. Virtually only the basal 30 feet of black fissile 

shale contains these nodules, and none have been found 

elsewhere in the stratigraphic section in this region. 

Interbedded with the black shale are thin beds of very 

fine grained thinly laminated sandstone that contain 

surficial casts of worm trails and· similar "spaghetti" 

markings. In, the upper, more sandy part of the member, which is some 300 feet thick, molds and prints of 

mollusks collected by W. T. Pecora and Joe H. Kerr in 

1952 were identified by W.A. Cobban, of the U.S. Geological Survey, as I nooeramu,s bellev'lWn8is Reeside., 

Ostrea larimeren8is Reeside, ,and Ostrea noot'llten8is 

Reeside, which are indicative of Albian ag~~ 

In an easterly distance of 30 miles along the Bearpaw 

Mountains structural arch, spherulitic nodules have 

been found wherever the contact between the Kootenai 

Formation and overlying Colorado Shale is well exposed. In the eastern part of the mountains, near 

Cleveland, several domes in an area of about 60 square 

miles afford excellent exposures, whereas in the western 

part, metamorphism has somewhat inhibited liberation 

of the nodules from enclosing rock. 

Black shale enclosing the phosphatic nodules is nonfossiliferous and free of other nodules or concretions ' such as those of carbonate, pyrite, or barite that occur 

in shale at other stratigraphic horizons in the region. 

The shale is laminated and composed of the typical 

ultra fine grained platy minerals (clay and mica) and 

angular to subrounded grains of quartz. Chemical 

analyses of unweathered basal shale that was free of 

.... 
ARTICLE 12 B-31 

phosphatic nodules and sandstone (tables 12.1 and 12.2) 

show very little phosphorus; the samples were collected 

along a trench 30 feet long. A pyrite content of 0.04 

percent is indicated by assigning all the S in the analysis to FeSz. The amounts of organic mUJtter ( 1.91 

percent)· and sulfur ( 0.02 percent) are substantially 

less than those reported by Rubey ( 1930, p. 8) for 

black shales higher in the Colorado Shale equivalents 

in the Black Hills region. .Poverty in C02 characterizes 

all these black shales. 

TABLE 12.1.-Chemical analyses of basal 30 feet of Colorado Shale 

and composite 'samples of fragments of phosphatic silt rind and 

internal spherulites of phosphatic nodules, Suction Creek, 

Bearpaw Mountains, Mont. 

[Analysts, with exceptions noted in footnotes: Black shale, P. L. D . Elmore and 

K. E. White; black rind and spherulites, L. M. Kehl] 

Black shale Rlack rind Spherulites 

Si02---------------------- Ah0a--------------------- Fe20a -------------------- FeO ________________ _____ _ ~gO ______ ___ ___________ _ Cao __________ ____ ____ __ _ 

N a20 _ - - - - --------------- K20 __ ___ ___ _____________ _ H2o- ________ _____ _____ ___ } H20+ ____ _____ ___________ _ 

Ti02--- ------------------ P205 --------- ------------ F ___ _____________ _______ _ s _____ ______ ______ ______ _ ~no ____________ ___ _____ _ BaO ____ ___ _____________ _ c _______ _____ ___________ _ C02- -_--- _------- ___ -_- __ 

Less 0 for F ____ __ ________ _ 

' Analyzed by E. J. Tomasi. 2 Replicate, 1.89. a Replicate, 2.15. 4 Analyzed by J. J. Fahey. 

61. 4 

19. 1 

2. 5 

3. 1 

1.4 

. 54 

. 53 

2. 4 

6. 2 { 

1. 1 

. 16 

4 <· 02 

. 12 4 1. 91 

. 05 

100. 53 

19. 46 

5. 13 

. 99 

. 83 

. 50 

37. 81 

. 35 

. 67 

. 46 

1. 78 

. 41 

27. 71 1 2 1. 93 

. 03 

. 09 

. 08 1 • 80 1 1. 22 

100. 25 

. 81 

99. 44 

4. 46 

1. 10 

7. 02 

. 47 

. 30 

46. 22 

. 16 

. 04 

. 35 

1. 65 

. 07 

33. 92 1 3 2. 25 

. 04 

. 08 

. 00 1 • 49 1 • 90 

99. 52 

. 95 

98. 57 

TABLE 12.2.-Semiquantitative spectrographic analysis of 10 

phosphate nodttles ancl enclosing black shale, Suction Creek, 

B earpaw Mountains, Mont. 

[Analyst: Harry Bastron] 

10 nodules 

o.x _________________ _ Mn, 'l'i 

.ox _____ ·___________ _ Ba, Sr, Zr, Y, La 

.oox ________________ Cu, Zn, Co, Ni, Cr, v 

.ooox _______________ Ag, sc 

Shale 

Ti 

Mn, V, Sr, Zr, La 

Cu, Zn, Co, Ni, Ga 

Sc 

NOTE.-Equivalent uranium (by B. A. McCall) 0.001 in 

nodules, 0.002 in shale. 

SPHERULITIC PHOSPHATE NODULES 

The phosphatic nodules are typically "bumpy" and 

"warty" (fig. 12.1) and have a maximum diameter of 4 

inches. Most of them range from lj2 to 2 inches in size 

and are globular to spheric in form. The nodules are 

conspicuously strewn on weathered surfaces or nested 

in soft shale, but trenching below grass-roots level reveals their isolated, random distribution in the shale, 

without preferential orientation. Nodules are easily 

removed intact from their original sites in unweathered 

shale. Laminae in the shale abut sharply against each 

nodule at its equatorial region and arch over and under 

at the polar regions. Laminae or bedded structures are 

absent in the nodules themselves. The spherulitic character of the nodules is observed only in broken specimens. Even in their densest concentration the nodules 

make up less than 2 percent of the black shale. 

J!..,IGURE 1.2.1.-Globular phosphate nodule from basal Colorado 

shale, Suction Creek, Bearpaw Mountains, Mont. 

INTERNAL STRUCTURE 

Sawed or broken nodules show two principal lithologic features-a homogeneous, black, phosphatic silt 

that forms a peripheral zone or "rind," and one or more 

internal phosphatic spherulites (fig. 12.2). Some 

nodules, particularly those of simple, spheric form and 

of small size, contain but one spherulite; most, however, 

contain several ·that are imbedded in phosphatic silt. 

The warty and bumpy nodules contain many spherulites, with each protuberance indicative of a spherulite. 

As many as 20 to 30 have been counted in single specimens. No direct relation exists between size of nodule 

and proportion of phosphatic silt to spherulite. Every 

one of hundreds of nodules examined shows spherulitic 

development. In many well-weathered specimens, the 

black envelope is absent and the surface of the nodules 

is pitted. In aggregate spherulites, the black matrix 

is like the rind in appearance and composition. The 

contact between spherulite and black rind within the 

nodules (fig. 12.2) is commonly marked by yellow-white 

veins. The central part of a spherulite either is a void 

that is lined with a botryoidal crust or it is filled with 

other minerals. 
B-32 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

FIGURE 12.2.-Polished slab of a phosphate nodule showing phosphatic rind, spherulites, and veins. 

COMPOSITION 

A grab sample of 13 nodules, analyzed by H. F. Phillips and P. W. Scott, of the U.S. Geological Survey, 

contains 33 percent P20s. 

The matrix phosphatic silt enveloping the spherulites 

within each nodule is nonfossiliferous, structureless, and 

homogeneous, and it is composed of very fine grained 

angular quartz grains and mica in an opaque matrix. 

Locally, coarser quartz grains are abundant. A chemical analysis of selected fragments of this silt (table 

12.1) reveals less Si02 than the shale, but more CaO, 

P20s, F, and C02. Supplementary X-ray examination 

by J. M. Axelrod and Z. S. Altschuler of the U.S. Geological Survey establishes the presence of carbonatefluorapatite. The fact that apatite is the only identified 

phosphate mineral to account for the peculiar chemical 

composition of the silt suggests that it must exist as a 

microcrystalline cement in the black silt of the nodules. 

The spherulites, on the other hand, are composed of 

well-crystallized carbonate-fluorapatite in three habits: 

( 1) Prismatic, elongate, and radially developed to form 

the spherulite itself; ( 2) veins and patches of microbotryoidal apatite parallel to or traversing the spherulitic fibers; and ( 3) mammillary, botryoidal crusts 

that line cavities and cracks in the spherulites. A 

chemical analysis of selected fragments of spherulites 

(table 12.1) shows high P205 and F contents. 

Among the veins in the nodules, those that are 

typically curvilinear septa between the spherulites and 

black rind are composed of chlorite, apatite, quartz, and 

pyrite. The apatite normally forms a crust along both 

borders of these veins. Similar veins occur in, or project from the septa into, both the rind and spherulites. 

Some are composed only of apatite or of apatite and 

one or more vein minerals. 

Quartz diminishes in amount in phosphatic silt that 

is but partly spherulitized. Petrographic relations at 

the termini of spherulitic fibers (fig. 12.3) against the 

FIGURE 12.3.-Photomicrograph showing spherulitic growth of fibers in phosphatic silt of nodule (3.5 X 2 em). 
ARTICLE 12 B-33 

black silt in the envelope or interior part of nodules 

strongly suggest in situ growth of the fiber by replacement or by recrystallization of the homogeneous phosphatic silt. 

The cavities in the central part of a spherulite are 

lined, like the veins, with a thin layer of botryoidal 

apatite with or without chlorite, pyrite, and quartz. 

Some mtv.ities are filled or partly filled with pyrite, 

which alters to limonite. Rttrely, barite is the cavityfining mineral, instead of pyrite. Both pyrite and· 

barite have not been seen in the same cavity. 

EFFECT OF MET AMORPHISM 

Thermal metamorphism of shale to hornfels in some 

places within the mountains has effected changes in 

the phosphatic nodules. Secondary quartz-chlorite 

veins are more abundant. Pyrite and limonite are 

rarely preserved although vestiges remain in some 

places. Better crystallization of the. apatite characterizes heat-altered nodules, for well-terminated, 

gemmy crystals of apatite occur in many cavities in 

associntio11 with tablets of chlorite but are unknown 

. in the unmetamorphosed spherulites. The phosphatic 

siltstone rind and matrix of the spherulites is "blacker" 

and carbonaceous bands and areas are locally 

accentuated. 

ORIGIN OF SPHERULITIC STRUCTURE 

V\T e believe that the nodules were originally homo1 O'eneous phosp 1atlc . s1. 'I t' . "bl d" ty concre IOns 1n u,e mu 

( = bhH~k shnJe). The carbonate-fluorapatite in the 

rnatrix later recrystallized to form spherulites resulting 

in a net loss of volume that permitted veins and cavityfilling mineralization. Quartz and . chlorite in veins 

can well be a product of internal recrystallization, but 

locally abundant pyrite requires derivation of sulfur 

from an external source. 

Field rehttions show that the spherulitic structure 

developed prior to the thermal metamorphism and deformu.tion thn.t accompanied igneous intrusions in 

rniddle Tertiary time; but early transformation of origimtlly ·homogeneous phosphatic silt to spherulites by 

some process of static metamorphism (diagenesis) is 

n.ll that can be concluded from our information. 

OTHER OCCURRENCES OF PHOSPHATIC SPHERULITES 

Phosphatic spherulites are well known in the basal 

pa,rt of the Thermopolis Shale (=basal Colorado 

Shale) in Park County, 1Vyo. (Pierce and Andrews, 

1940, p. 121) and were described as dahllite by McConnell ( 1935). ~L R. l{]epper (written coml1U.lnication, 1955) has provided spherulitic apatite nodu1es 

from basal black shale ( =Skull Creek ( ~) of the Colorado sequence) about 50 feet above a basal sandstone 

member (=Fall R-iver(~)) that overlies the l(ootenai 

Formation in Broadwater County, southwestern Montana. The existence of phosphatic nodules in basal 

black shale of the Lower Cretaceous sequence over 

several hundred squ:are miles thus provides a welldefined stratigraphic datum and poses a regional problem in sedimentology. 

Spherulitic phosphate nodules in Silurian shale in 

the Dneister River basin of the Podolia Province, 

Russia, reported by Schwackhofer ( 1871) and O'Reilly 

(1882) and described as a new mineral "podolite" by 

Tschirwinski (1907) ·were shown by Schaller (1912) 

to be structurally identical with dahllite. A sample 

(No. 103116) provided to us by the U.S. National 

Museum is identified as carbonate-fluorapatite 

(=francolite) and is virtually identical with the Wyoming spherulites. · Spherulitic phosphate nodules ·in 

Cretaceous and yOl~nger formations in the eastern part 

of the Donetz basin are reported by Orekhov ( 1958). 

Spherulitic nodules may be more widespread than heretofore reported in the geological literature . 

ORIGIN 

The occurrence of spherulitic phosphate nodules poses 

a dual problem: ( 1) Origin of the original homogeneous discrete nodules, and ( 2) development of the 

spherulitic structure. We believe that abundant information exists ii1 the geologic literature to suggest that 

these nodules formed as concretions at numerous nucleation loci in unconsolidated mud on the sen floor by 

precipitation of microcrystalline carbonate-fluorapatite 

from sea water. '" e seek some hydrogeochemical process by which this phenomenon can form discrete concretions randomly distributed within "blue mud" over 

hundreds of square miles, and conclude that geologic 

relations provide the best clues. 

Marine shale of Cretaceous age, stratigraphically 

hio-her than the spherulitic phosphate horizon in the 0 • 

Bearpa w Mountains, contains calcareous concretiOns 

with varying proportions, of Ca, Mg, Fe, and Mn. Many 

of these concretions, septarian. or homogeneous, contain 

unbroken delicate fossil shells, like Baeul'ites, and were 

probably formed before compaction of the shale was 

completed (Clifton, 1957). An analogy in authigenic 

process for origin of the calcareous and phosphatic 

concretions at different horizons in the Colorado Shale 

is likely, although carbonate and phosphate concretions 

are not formed at the same horizon. Mutual exclusion 

has also been noted by Abele m1d McGowran ( 1959, 

p. 311) for Lower Cambrian phosphate nodules in South 

Australia. 
B-34 GEOLOGICAL SURVEY RESEARCH 19 6 2 

GEOLOGIC CONSIDERATIONS 

Phosphorites are widely distributed in the geologic 

column. Most of them," however, are phosphatic shales 

interbedded with sandstone, limestone, chert, or ghiuconitic greensand and are characterized by phosphatized 

fossil fragments, oolitic pellets, or smooth pebble-like 

units with rock, mineral, or fossil nuclei. Fossil fragments commonly are entirely replaced by phosphate or 

are armored by pelletal colloform apatite. 

Phosphatic nodules dredged from the sea floor 

(Murray and Renard, 1891; Dietz and others, 1942; 

Emery and others, 1952) at depths up to 11,000 feet are 

slabby to rounded and composed of rock, mineral, bone, 

and foram fragments cemented and coated by microcrystalline phosphate. The nodules are most abundant 

on shelves and banks near continental borders where 

cold and warm water currents meet. One nodule from 

the Coronado Bank, provided to us· by F. R. Shepard, 

is composed of a heterogeneous mixture of subangular 

detrital fragments (quartz, plagioclase, hypersthene, 

hornblende, tourmaline, sphene, biotite, and porphyritic 

andesite) in a matrix of dark submicroscopic carbonate 

fluorapatite containing irregularly distributed threadlike areas of greenish chlorite. Neither spherulitic 

structure nor carbonate is present in the nodule. 

SOURCE OF PHOSPHORUS. 

Phosphate to form concretions in the Colorado Shale 

was most likely derived from sea water tr~nsgressing a 

broad shelf area in Early Cretaceous time rather than 

from alteration of excreta or calculi of marine animals. 

Many investigators have recorded a systematic variation of the phosphoric acid content of sea water as a 

function of temperature, depth, pH, and season (Matthews, 1917; Atkins, 1928). · Surface oceanic waters, 

through the activity of organisms, become impoverished 

in plant nutrients such as phosphate and nitrate, and 

deeper waters become enriched by "mineralized" organic matter falling to the sea bottom. Thomsen ( 1931, 

1937) reported about 100 to 200 mg per m3 P 20 5 at 

depths of about 3,000 m in several oceans, and Atkins 

( 1925, 1928) reports an increase from 8 mg per m3 

P205 at 100 ~ depth (T=15.1 °C) to 88 mg per m3 

P205 at 3,000 m depth (T=3.1 ° C) in the Atlantic Ocean 

between the Canary Islands and Lisboa. 

Kazakov (1938, 1950) stated that his experimental 

studies of the equilibrium system Ca0-P20 5-H20 and 

Ca0-Pt05-HF-H20-C02 suggested that precipitation 

of phosphate probably does not occur in the· phytoplankton zone on oceanic shelf areas, and that all the 

phosphate precipitated below that zone would be apatite in association with calcium carbonate. We do not 

support Kazakov's conclusion, however, that precipitation of calcium carbonate must precede that of apatite 

in sea water. C02 in apatite analyses, normally assigned to CaCOa as a separate phase mixed with apatite 

(Kazakov, 1938), is currently interpreted· (Altschuler 

and others, 1952) to be a component of a single structural phase. Bottom m"!lds containing organic matter, 

apatite, and sulfide would require, with reference to the 

Eh-pH diagram of Krumbein and Garrels ( 1952), a 

hydrogeochemical environment of pH above 7 but less 

than 7.8, and of Eh in the negative region (Swanson, 

1961). Higher pii and positive Eh would favor precipitation of carbonate and sulfate. In the mud-bottom 

habitat represented by the basal Colorado black shale, 

any preexisting CaCOa phase would not be in equilibrium and would be dissolved, replaced, or armored by an 

apatite aureole, according to . our interpretation. As 

indicated by the Cretaceous system in Montana and 

Wyoming, and as earlier noted by McKelvey and others 

( 1953) for part of the Phosphoria Formation of Permian age, first carbonate-fluorapatite, and later CaCOa, 

were precipitated as the transgressive sea ascended the 

shelf. 

CONCLUSIONS 

Phosphate nodules in basal marine Colorado Shale 

in the northern Great Plains of Montana and "\Vyoming 

record a special situation of a widespread transgressive 

shelf sea where bottom muds were accumulating beyond 

the influence of nearshore turbulent conditions and at 

a depth greater than the base of the zone of photosynthesis. Environmental hydrochemical conditions of the 

bottom slimes and water are low pH, reducing conditions, high partial pressure of C02, and high concentration of Ca, _P, F, and H 2S. Only soft-bodied 

animals were present. Precipitation of carbonatefluorapatite occurred first as a concretionary microcrystalline cement in silt prior to final compaction of the 

bottom mud shale. The phenomenon is most likely a 

result .of saturation in P 20 5 caused by a rise in pH and 

temperature to disturb the apatite solution equilibrium 

in upwelling ocean water. -These ·concretions later recrystallized diagenetically and developed apatite 

spherul1tes and secondary veins. 

REFERENCES 

Abele, C., and McGowran, B., 1959, The geology of the Cambrian 

south of Adelaide: Royal Soc. South Australia Trans., v. 82, 

p. 301-320. . 

Altschuler, Z. S., Cisney, E. A, and Barlow, I. H., 1952, X-ray 

evidence of the nature of carbonate-apatite [abs.] : Geol. 

Soc. America Bull., v. 63, p. 1230-1231. 

...... 
.J"r 

• 

-J .. 

ARTICLE .13 B-35 

Atkins, \V. R. G., 1925, The phosphate· content of fresh and salt 

waters in its relationship to the growth of algal plankton: 

Marine Bioi. Assoc. Jour., [United Kingdom], v. 13, 

p. 119-150. 

--- 1928, Seasonal variations in the phosphate and silicate 

content of sen water: Marine Bioi. Assoc. Jour., v. 15, 

p. 191-205. 

Clifton, H. E., 1957, Carbonate conct·etions of the Ohio shale: 

Ohio .Tour. Sci., v. 57, p. 114-129. 

Dietz, R. S., Emery, K. 0., and Shepard, F. P., 1942, Phosphorite deposits on the sea floor off southern California : Geol. 

Soc. America Bull., v. 53, p. 815-847. 

Emery, K. 0., Butcher, \V. S., Gould, H. R., and Shepard, F. P., 

1952, Submarine geology off San Diego, California: Jour. 

Geology, v. 60, p. 511-549. 

Kazakov, A. V., 1938, ~rhe phosphorite facies and the genesis 

of phosphorites, vn Geological investigations of agricultural 

ores U.S.S.R.: Sci. lust. Fertilizers and Insectofungicides 

'l'rans. (U.S.S.R.), no. 142, p. 95--113. (Special issue in 

l!Jnglish published for 17th Internat. Geol. Cong.) 

---1950, Fluorapatite system equilibria under conditions of 

formntion of sedlmentnry rocks: Akad. Nauk SSSR Inst. 

Geol. Nnuk 'l'rudy, Vyp. 114, Geol. Ser. no. 40, p. 1-21. 

Krnmbein, \V. C. nnd Garrels, R. 1\:l., 1952, Origin and classification of chemical sedi.ments in terms of pH and oxidationreduction potentinls: Jour. Geology, v. 60, p. 1-33. 

Mntthews, D. J., 1917, On ,the amount of phosphoric acid in the 

sen wtlter off Plymouth Sound: Marine Bioi. Assoc. Jour., 

v. 11, p. 251-257. . 

McConnell, Duncan, 1935, Spberulitic concretions of dahllite 

from Ishnwoon, \Vyoming: Am. Mineralogist, v. 20, p. 693-

698. 

McKelvey, V. 1D., Swanson, R. \Y., and Sheldon, R. P., 1953, The 

Perminn phosphorite deposits of western United States in 

Giulhnm, P. I.J. R., ed., Paper XI in Origine des Gisements 

de phosphates de chaux: Internat. Geol. Cong., 19th, Algiers, 1952, Comptes rendus, sec. 11, pt. 11, ·p. 41>--64. 

Murray, .J., and Renard, .A. F., 1891, Report on the scientific 

results of the exploring voyage of· H.M.S. Olwlle'ltger, 1873-

76, Deep sea deposits, p. 396-400. 

O'Reilly, J. P., 1882, The phosphorite nodules of Podolia: Royal 

Soc. Dublin Proc., v. 4, p. 215--222. 

Orekhov, S., 1958, Mineralogy and structural types of phosphorites of the Rostov region [translation of abstract] : 

Uchenye Zapiski Rostov-na Donn Gosudarst Univ., v. 53, 

p. 273-287. 

Pierce, \V. G., and Andrews, D. A., 1940, Geology and coal resources of the region south of Cody, Park County, Wyoming; U.S. Geol. Survey Bull. 94:1-B, p. 99-175. 

Rubey, \V. \V., 1930, Lithologic studies of fine-grained Upper 

Cretaceous sedimentary rocks of the Black Hills region : 

U.S. Geol. Survey Prof. Paper 165--A, 54 p. 

Schaller, \V. T., 1912, 'I'he .Probable identity of podolite with 

dahllite in Mineralogic notes, series 2:. U.S. Geol. Suney 

Bull. 509, p: 96-97. 

Schwackhofer, Fr., 1871, Ueber die Phosphorit-Einlagerungen 

an den Ufern des Dniester in russich und osterreichisch 

Podolien und in der Bukowina : K. K. Geol. Reichsanstalt 

.Jahrb., v. 21, p. 211-230. 

Swanson, V. E., 1961, Geology and geochemistry of uranium in 

marine black shales, a review: U.S. Geological Survey Prof. 

Paper 356-C, p. 67-112. 

Thomsen, H., 1931, Nitrate and phosphate contents of Mediterranean water : Danish Oceanographic Expedition Rept., 

1908-10, v. 3, misc. papers, no. 6, 14 p. 

---1937, Hydrographical observations made during the Dana 

Expedition 1928-1930 : Dana Repts., no. 12, 46 p. 

Tschirwinski, W., 1907, Uber Podolite, ein Neues Mineral: Centralbl. Mineralogic, p. 279-283. 

13. STREAM DIRECTIONS IN THE LAKOTA FORMATION (CRETACEOUS) IN THE NORTHERN BLACK HILLS, 

WYOMING AND SOUTH DAKOTA 

By WILLIAM J. MAPEL and CHARLES L. PILLMORE, Denver, Colo. 

The Lakota Formation of Early Cretaceous ~1-ge is 

100 to 250 feet thick in the northern Black Hills. It 

consists hugely of sandstone, siltstone, and claystone deposited on the flood plains of streams. The formation 

and its regional stratigraphic relations in the Black 

II ills have been described by vVaage ( 1959), Mapel and 

Gott ( 1959), and Post and Bell ( 1961). 

Sandstone beds in much of the Lakota Formation 

are conspicuously crossbedded in sets a few inches to 

about 3 feet thick. At places the crossbeds dip as steeply 

as 30°. The crossbedded sandstones are mostly medium 

to coarse gt:nined and at. many places contaip lenses of 

granules and small pebbles. 

'I' he dip directions of the cross beds were determined 

at 65 localities between Devils Tower and Newcastle on 

the west side of the Black Hills and at 20 localities near 

Aladdin at the north end of the Black Hills (fig. 13.1) 

to establish the direction of flow of streams that deposited the sediments. Dip directions of from 10 to 20 

sets of crossbeds were averaged. to find the dip direction 

at each locality. Directions from place to place are 

greatly diverse, but fairly definite trends become apparent if the dip directions are averaged for localities · 

grouped according to geographic location, stratigraphic 

. position, or both. Four such groupings are shown on 

figure 13.1 and a statistical analysis of the results is 
B-36 GEOLOGICAL SURVEY RESEARCH 19 6 2 

T. 

53 

N. 

T. 

52 

N. 

T. 

51 

N. 

T. 

50 

N. 

North 

South 

ALADDIN AREA 

R. 65 W. 

Devils Tower 

T. 

49 

N; 

R. MW. 

T. 

56 

N. 

T. 

55 

N. 

T. 

54 

N. 

Crook'Courity --weston couiit_y __ 

Outcrops of the Fall River, Lakota, and 

Morrison FOrmations, and the outline of 

the area examined, Black Hills 

T. 

48 

N. 

T. 

47 

N. 

T. 

46 

N. 

\ \ 

- X f-. Aladdin 

R. 63 W. R. 62 W ~ 

R. 

EXPLANATION 

J 

Average dip direction of crossbeds. 

Dot shows locality; number shows 

stratigraphic unit. 

North South 

Fall River Formation 

~}Lakota .) - l J'or-

-- mation 

Morraon l'o:rution 

61 w. 

Diagrammatic section showing stratigraphic units in the Devils TowerNewcastle area for which dip directionS 

of crossbeds were determined; units 

not differentiated in the Aladdin area. 

Uneven lines show disconformities. 

\ Inyan Kara 

Mountain 2 

2\) 

1/ 

'1 

1--

1/ \11 ~ l{ / ...._..... 

1/ 

f1 1 

l 

t~ 

1/ 

10 15 Miles 

,~!' 0 oc:: ~ ~ g North ~·~u 

Oi:z:~ I >- .... " !II: :;,IQ __ 

•0 Ill) 

!f ~ T. 

8 

I._ N. 

I 

R.60W.~. 

North 

South 

North 

South 

North 

South 

DEVILS TOWER-NEWCASTLE AREA 

FIGURE 13.1.-Dip directions of crossbeds, northern Black Hills. Map and diagrams summarize dip directions of 

1,184 sets of crossbeds at 85 localities. 

.... 

·~ 
"""' 

ARTICLE 14 B-37 

given in the table below. A resultant dip direction of 

about N. 60° W. was found in an area south of Devils 

Tower in and near Tps. 49 to 51 N., Rs. 64 and 65 W. 

(stratigraphic unit 2) . In the other three areas analyzed, resultant dip directions vary from N. 40° E. to 

N. 75° E. and average about N. 60° E. Trends to the 

northwest and to the northeast or east also can be read 

from figure 13.2, where all the measured dip directions· 

are plotted. 

Statistical analysis of data 

Number 95-percent Stand- ConsistGroup of Resultant confidence ard df'vi- ency measure- dip direction interval ation ratio 1 

ments (degrees) 6degrees) 

Devils Tower-Newcastle area: Unit!_ _______ 359 N.400 E. ±9 84 0. 34 Unit 2 ________ 492 N.60° w. ±9 100 . 22 Unit 3 ________ 112 N.75° E. ±15 82 . 37 

Aladdin area _______ 221 N.45° E. ±12 94 . 27 

1 Obtained by dividing the length of the resultant direction 

vector by the number of measurements. 

The data indicate a complicated local pattern of 

stream flow such as would result from meandering 

streams that flowed generally northward. Similar 

conclusions regarding the direction of stream flow have 

been made for areas in the southern Black Hills by 

Russell (1928, p. 135), who reports a dominant northwestwn,rd dip of crossbeds in the Lakota near Hot 

Springs, and by Brobst (1956), who reports a northwestwnrd alinement of stream channels south of 

Newcastle. 

REFERENCES 

Brobst, D. A., 1956, Channel sandstones, southern Black Hills, 

in Geologic investigations of radioactive deposits-SemiSouth 

FIGURE 13.2.-Summation of dip directions of all cross· 

beds measured, northern Black Hills. 

annual progress report, June 1 to Nov. 30, 1956: U.S. Geol. 

Survey TEI-640, p. 102-108, issued by the U.S. Atomic 

Energy Comm. Tech. Inf. Service, Oak Ridge, Tenn. 

Mapel, W. J., and Gott, G. B., 1959, Diagrammatic restored 

section of the Inyan Kara group, Morrison formation, and 

Unkpapa sandstone on the western side of the Black Hills, 

'Vyoming and South Dakota: U.s.· Geol. Survey Mineral 

Inv. Field Studies Map MF-218. 

Post, E. V., and Bell, Henry, III, 1961, Chilson member of the 

Lakota formation in the Black Hills, South Dakota and 

Wyoming: Art. 349 in U.S. Geol. Survey Prof. Paper 

424-D, p. D173-D178. 

Russell, W. L., 1928, The origin of artesian pressure: Ecpn. 

Geology, v. 23, no. 2, p. 132-157. 

Waage, K. M., 1959, Stratigraphy of the Inyan Kara group in 

the Black Hills: U.S. Geol. Survey Bull. 1083-B, p. 11-90. 

14. FORMATION AND DEPOSITION OF CLAY BALLS, RIO PUERCO, NEW MEXICO 

By CARL F .. NoRDIN, JR., and WILLIAM F. CURTIS, Albuquerque, N. Mex. 

The environment of the Rio Puerco in New Mexico 

is ideally suited to the formation of clay balls. The· 

stream is characterized by ephemeral runoff from local 

storms of short duration and high intensity. Clays 

derive"l from weathered shales, primarily the Chinle 

Formation of Triassic age and the Mancos Shale of 

Cretaceous age, are readily available on the denuded 

watershed. Flows carry extremely high concentrations 

of fine materials in suspension. 

Deposits of clay balls 'vere observed at a reach of the 

Rio Puerco near Bernardo in 1961 (fig. 14.1). During 

the summer, the sand bed of the channel was impregnated with clay to a depth of about 0.5 foot (fig. 14.2A). 

By early fall, a headcut had moved upstream through 
B-38 GEOLOGICAL SURVEY RESEARCH 19 6 2 

N 

I 

1000 0 1000 2000 FEET I I I I I I 

,.---- ---, 1 

I 

I 

I 

LrI 

I 

I 

I 

I 

_____ j 

FIGURE 14.1.-Sketch map of study reach, showing deposition 

pattern of clay balls. 

the study reach, cutting a trench about 3 feet deep and 

30 feet wide in the channel (fig. 14.2B). The cut exposed numerous deposits of clay balls. 

The clay balls are of two types--armored and unarmored. Those that formed on and moved over the 

clay-impregnated bed are not armored (fig. 14.20) 

and contain negligible amounts of sand and pebbles. 

Those that formed on and moved over the sand bed 

are armored with sand and pebbles in a clay matrix 

(fig. 14.2D, E). Armor comprises 15 to 75 percent of 

the weight of the balls. Bell ( 1940) found a close relation, between surface area and weight of armor for 

mud balls observed in Las Posas Barranca, Ventura 

Co~u1ty, Calif. A siinilar relation was found for the 

armored clay balls of the Rio Puerco, although the 

weight of the armoring for a given surface area was 

about llh times as great as that found by Bell. 

Some of the balls have no perceivable internal structure, some have concentric structure, and some have 

laminated structure. Some of the cl_ay balls have a 

composite structure; for example, a structureless core 

with concentric layers of clay or armor or both (fig. 

14.2E) or a lamipated core (fig. 14.2F) surrounded by 

concentric layers. 

Most of the balls show no core structure. There is 

no evidence to suggest that the cores remained dry 

during formation and transportation, as was found by 

Bell (1940). Rather, the lack of structure suggests 

that the core material may have been damp at the time 

of formation and that the plastic material was deformed sufficiently during transportation to destroy all 

vestiges of structure. Conversely, cores that have definite structure (fig. 14.2F) certainly must have remained 

dry on the interior during the period of formation and 

transportation, otherwise these structural features 

would have been distorted or destroyed by plastic deformation. 

Curve A on figure 14J3 is the size distribution of core 

material of the clay balls. Curve B shows the size distribution of typical suspended-sediment samples collected in flow over the clay-impregnated bed. Curves 

A and B are similar. They indicate that the cores of 

the balls are formed :from clay that was carried in suspension during flow and was deposited in depressions 

of the bed. Curve 0 shows the size distribution of the 

clay-impregnated layer of the bed and is very close to 

the size distribution of the sediment forn1ing the banks. 

Curve 0 indicates that the material comprising the clay 

balls is not derived primarily from bank sloughing or 

from headcutting through the clay-impregnated bed. 

The cores of the balls contain about 65 percent clay, 

whereas the material from bank sloughing and from 

headcutting through the clay-impregnated bed contains 

less than 30 percent clay. CurveD shows the average 

size distribution of bed material that is not impregnated 

with clay. Curve E shows the average size distribution 

of the armor from the clay balls. Two points of interest 

are notable in curve E : The armor contains about 40 

percent silt and clay as binding material, and more than 

15 percent of the al'lllor consists of material coarser than 

1 mm. However, sieve analysis indicates that material 

coarser than 1 mm forms less than 0.2 percent of the 

bed material. 

Clay balls selectively accrete the coarser portion of 

the bed material probably because angular, coarse 

particles penetrate farther into the ball and adhere to 

the clay more firmly than do the sinaller, well-rounded 

sand grains. 

The size distribution of the clay balls was determined 

in the field by measuring the diameter of 406 of the 

balls selected at random from 3 separate deposits. The 

maximum size observed was 400 mm (about 16 inches). 

The size distribution, shown in figure 14.4, is almost 

precisely log-normal. The slight tendency for a distri-

-, 

I~ 
ARTICLE 14 

A 

B 

c 

... - - 2 - t:>-

~; -"' - "-

D 

E 

F 

FIGURE 14.2.-Study reach and clay balls, Rio Puerco near Bernardo, N. Mex. A, Study reach, view upstream, 

summer. B, Study reach showing trenching, fall. 0, Typical unarmored clay balls. D, Deposit of armored 

clay balls. E, Concentric structure, armored clay ball. F, Laminated structure, core of clay ball. 

B-39 
B-40 GEOLOGICAL SURVEY RESEARCH 19 6 2 

a:: 

0.001 

Clay 

0.004 I Silt 

0.062 2.0 

Sand I Gravel 

99~----~~r------.--.~--~~-.----~~-, 

95~----~~~----~~--~,_~~~~--T-~ 

~ 80~~~~~----~q_-1~~--~~------T--; u: 

1- 60 

ffi40~--~~~~----~~------;-~------T--1 

~20~----~~~--~~-1------;-~------T--; 

LIJ 

~ 5~----~~r-----;-~------;-~------~-, 

1~-----L--~----~~~----~~~----~-7 

0.001 0.005 0.01 0.05 0.1 0.5 1.0 5 10 

DIAMETER, IN MILLIMETERS 

FIGuRE 14.3.-Typical particle-size m_stributions. 

bution skewed toward the smaller sizes probably reflects the difficulty of accurately measuring the smallest 

sizes. The median diameter is 50 mm, and there was no 

difference in the size distribution of the three deposits. 

All of the balls exhibited a high degree of sphericity. 

In the reach studied, the clay balls were deposited 

with remarkable regularity (fig. 14.1) in groups or bars, 

roughly parallel to the channel. The distance between 

deposits ranges from 4 to 8 times the channel width. 

This pattern of deposition corresponds closely to the 

pattern of meanders or riffles given by Leopold and 

Wolman (1960), who show that the .meander wavelength or twice the distance between successive riffles is 

approximately 10 times the channel.width. 

Clay balls probably will be formed if the following 

three conditions are satisfied: . 

1. A source of clay material is availa?le. 

2. Fragments of source material possess sufficient 

strength to maintain their identity. 

3. The flow is strong enough to move the fragments 

and to maintain motion until th£>,y are rounded to form 

clay balls. 

After every flow, clay is deposited in depressions of 

the bed. When dried, this material cracks and curls, 

and the fragments formed may range in size and shape 

from paper-thin flakes to polygonal chunks several feet 

thick. Thus, flakes formed by surface cracking are 

available in sizes that will be moved by flows of almost 

any intensity. 

The deciding factor for the formation of clay balls 

is the requirement that the source material possess 

sufficient strength to maintain its identity for the duration of the flow. The strength of the cb.ys of the Rio 

Puerco depends mainly on the water content. The 

material may range in moisture conditions from dry 

sheets, which develop maximum strength through an 

99 

95 

80 a:: 

LIJ 

z 

u: 60 

1-

z 

~ 40 a:: 

LIJ 

~ 20 

5 

1 

10 

/ 

ll 

v 

~v 

1/ 

L ~ 

v· 

20 40 60 80 100 200 400 600 

DIAMETER. IN MILLIMETERS 

FIGuRE 14.4.-Size distribution of clay balls. 

entire range of plastic material to a liquid slurry. Clay 

balls do not fC!rm after prolonged periods of flow, unde:r 

which conditions source material either is not available 

or is saturated and does not meet the strength 

requirements. 

REFERENCES 

Bell, H. S., 1940, Armored mud balls-their origin, properties, 

and role in sedimentation: Jour. Geology, v. 48, no. 1, p. 

1-31. 

Leopold, L. B., and Wolman, M. G., 1960, River meanders: 

Geol. Soc. America Bull., v. 71, p. 769-793. 

..-.: 
... 

... 

ARTICLE 15 B-41· 

15. ESTIMATING POROSITY FROM SPECIFIC GRAVITY 

By PHILIP CoHEN, Carson City, Nev. 

Work done in cooperation with the Nevada Department of Oon8ervation and Natu,ral Resources 

As a part of a hydrologic study, 115 samples of the 

unconsolidated deposits of a 40-mile segment of the 

flood plain n.nd terraces of the Humboldt River, Humboldt County, Nev., were collected in the summer of 

1960. Eighty-two undisturbed samples were collected 

by 1n.e~u1s of a 2-inch-diruneter Pomona core barrel; 

33 disturbed srunples also were collected. All of the 

snmples were collected from a depth less than 20 feet 

below ln . .nd surface. 

For all samples the dry unit weight (apparent specific gravity) m1d the 1\Verage unit weight of the particles 

comprising each sample (absolute specific gravity), 

were determined n.t the Hydrologic Laboratory of the 

Ground Water Branch of the Survey at Denver, Colo. 

From these data, porosity was determined by the foLlowing formula: 

where n = porosity, in percent by volume; 

y 8 = average unit weight of the particles comprising the sample in grams per cubic 

centimeter (absolute specific gravity) ; 

yr~ = dt·y unit weight of the dry undisturbed 

or repacked sample, in grruns per cubic 

centimeter (apparent specific gravity). 

The absolute specific gravity of the samples was 

determined by the pycnometer method (ICrumbein and 

Pettijohn, 1938, p. 501). The dry unit weight of the 

undisturbed cores was determined by measuring the 

volume and weighing the oven-dried cores; the dry 

unit weight of the disturbed samples was determined 

by measuring the volume and oven-dried weight of 

sa.m.ples that were repacked in the laboratory. 

It is apparent frmn the above equation that a graph 

with porosity as the abscissa, and dry unit weight as the 

ordinate will plot as a straight line for samples having 

the sn.me a.bsolute specific gravity ( a.verage unit weight 

of pn.rticles). This rela.tionship is true irrespective 

of other factors such as particle size, partic.le sha.pe, 

degree of assortment, sedimentary structures, or degree 

of compaction. For mineralogically or lithologically 

heterogeneous deposits, the points will tend to be scattered-the degree of scattering being related to differences in the absolute specific gravity of the samples. 

Figure 15.1 is a graph showing the rela.tion of porosity and dry unit weight of the samples of the Humboldt River valley. The points on the graph tend to 

define a straight line and fall in a very narrow band, 

indicating that the absolute specific gravity of the 

samples does not vary substantially. The deposits of 

the flood plain of the Humboldt River contain ma.ny 

different minerals and rock types derived largely from 

the erosion of Qua.ternary and Tertiary alluvial fa .. ns 

and Pleistocene lake deposits. It appears from the 

graph that the older deposits were thoroughly reworked 

and mixed by the Humboldt River, causing the resulting flood-plain deposits to have a fairly constant absolute specific gravity. 

Dry unit weight is equal to the average unit weight· 

when porosity is equal to zero (see equation), and the 

approximate average unit weight of the particles comprising all the samples can be obtained by extending 

the line shown in figure 15.1 so that it intersects the 

ordinate. Thus, the average unit weight of particles 

of the samples plotted is about 2.67. 

The aforementioned relations between porosity and 

dry unit weight can be useful in future hydrogeologic 

studies in the Humboldt River valley. In the present 

area of study, it is possible to use figure 15.1 to estimate 

·porosity from dry unit weight with an approximate 

accuracy of + 1.5 percent. This degree of accuracy is 

adequate for the present study. In order to estimate 

porosity from dry unit weight in other areas it ·will 

be necessary to determine dry unit weight, absolute 

specific gravity, and porosity of a sufficient number of 

samples to define the relation between these parameters. 

Once this relation is defined, it is necessary only to 

determine dry unit weight in order to estimate porosity. 

The relation between porosity and dry unit weight 

also may be useful in other areas where lithologic and 

stratigraphic control permits an accurate estimate of 

average unit weight of particles. If this value alone 

is known for any deposit, a straight-line graph similar 

to figure 15.1 can be drawn showing the relation between 

the dry unit weight and the porosity of the deposit. 

From the equation, it is apparent that the line must 
B-42 GEOLOGICAL SURVEY RESEARCH 1962 

2.7 

\ 

\ 

2.6 \ 

\ 

\ 

\ 

2.5 \ 

\ 

\ 

\ 

2.4 \ 

\ 

\ 

\ 

2.3 \ 

\ 

\ 

0:: 2.2 \ 

LLI \ 

t- \ 

LLI \ 

2 2.1 \ i= 

z 

LLI 

0 2.0 

0 

iii 1.9 .. ~ 

0 

0:: 1.8 LLI 

a.. 

(/) 

~ 1.7 

c:( ,•. 

0:: 

(!) 1.6 

z ·;· 

.... 1.5 ~ .. ~ ·- LLI ., 

~ 1.4 .. .... - z 1.3 ~ : 

... >-

0:: 1.2 

0 ... 

. :·•. 

I. I 

1.0 

0.9 \ 

\ 

•\ 

\ 

0.8 \ 

\ 

\ 

\ 

0.7 

0 10 20 30 40 50 60 70 

POROSITY, IN PERCENT 

FIGURE 15.1.-Relation between porosity and. dry unit weight in the Humboldt River Valley, Humboldt 

County, Nev. 

·~ 
; 

~~-

ARTICLE 16 B-43 

:intersect the abscissa, or zero dry unit weight line, 

where porosity equals 100 percent, and the line n1ust 

intersect the ordinate, or zero porosity line, at. the 

value of the ~werage unit weight of particles (absolute 

specific gravity) for the deposit. 

.At present, dry-unit-weight data are being collected 

by means of the nuclear density meter in many areas . 

.A few determinations of dry unit weight (apparent 

specific gravity) then may make' it possible to obtain 

~1 fttirly accurate estimate of the porosity and the absolute specific gravity of all the materials tested with 

the meter by use of a plot similar to that described. 

,,-•• 

The absolute specific gravity of any sample represented 

by a point plotted on a graph similar to figure 15.1 

could be ascer:ta.ined by drawing a straight line fron1 the 

100-percent p9rosity value on the abscissa through the 

point to the ordinate~ The dry-unit-weight value at 

the point of intersection of the line and the ordinate 

is equal to the absolute specific gravity of the sample. 

REFERENCE 

Krumbein, W. C., and Pettijohn, ~"'. J., 1938, Manual of sedimentary petrography: New York, Appleton-Century-Crofts, 

549 p. 

16. RELATION OF VOLUMETRIC SHRINKAGE TO CLAY CONTENT OF SEDIMENTS FROM THE SAN JOAQUIN 

VALLEY, CALIFORNIA 

By A. I. ,JOHNSON and D. A. l\{oRRis, Denver, Colo. 

More than 300 "undisturbed" samples taken from 

depths as great as 2,000 feet from 3 core holes in the 

Los Banos-l(ettleman City area, California, were 

analyzed in the Hydrologic Laboratory of the Geological Survey as part of an investigation of the 

physicaJ character of sediments in an area subject to 

land subsidence in the San Joaquin Valley (InterAgency Committee on La.nd Subsidence in the San 

.Joaquin Valley, 1958). 

Atterberg ( 1911) and Goldschmidt ( 1926) found 

thn,t plasticity is a function of the finer particles in a 

sediment mass. Therefore, the consistency limits and 

indices should vary according to the clay content. The 

relation of the liquid and plastic limits. a.nd of the 

pnsticity index to c1ay content has been shown (Atterberg, 191.1; Terzaghi, 1926; Russell and vVehr, 1928; 

and Baver, 1948). This paper sho\vs the close relationship between clay content and volumetric shrinkage. 

''Then fine-grained sediments are deposited in ·water, 

the mass has the appearance of a. dense fluid. I.f the 

water content of this mass is progressively i·educed, 

the sediment mass wHl pass from the liquid state, 

through a plastic state and a semisolid state, to-a solid 

state. The water content, in percent of dry weight, at 

the transition between the liquid and plastic states is 

called the liquid limit, at the transition between the 

plnstic and semisolid states is called the plastic limit, 

nnd at the transition between the semisolid and solid 

states is called the shrinkage limit. A decrease in 

629660-62---4 

volume of the sediments takes place continuously as the 

water content decreases to the shrinkage limit, which 

is the maximum water content, in percent of dry weight, 

at which a reduction in water content produces no 

further decrease in volume of the sediment mass. Volumetric shrinkage is the decrease in volume, in percent 

of dry volume, of the sediment mass when the water 

content is reduced from the liquid limit to the shrinkage limit. Volumetric shrinkage is computed by the 

equation 

Vs= ('wr,-~os)R, 

where V~=volumetric shrinkage, in percent of dry 

volume; 

wL= liquid limit, iri percent of dry . ~veight; 

'Ws=shrinkage limit, in percent of dry. weight; 

R =shrinkage ratio, in grams per cubic 

centimeter. 

The shrinkage ratio is defined as the ratio of a given 

change in volume, expressed as percent of the dry volume, to the corresponding change in water content 

above the shrinkage limit,· expressed as percent of the 

weight of the oven-dried soil. 

· The clay content (particles sma1ler than 0.0004 mm) 

was determined by the hydron1eter method. Clay content and volumetric shrinkage are plotted against 

depth (fig. 16.1) for one of the three core holes. A 

close comparison between clay content and volumetric 

shrinkage was also noted for the other twu core holes. 

The relation of clay content to volumetric shrinkage 

· for samples from all three core holes in the Los Banos-
B-44 

0 

GEOLOGICAL SURVEY RESEA:RCH 1 9 6 2 

..... 

UJ 

UJ 

LL. 

200 

400 

0 600 -~ 

.LJ' 

~ 800 LL. 

0:: 

:::> 

(j) 1000 

0 

z 

~ 1200 ~ 

0 

..J 

~ 1400 

:t 

..... 

~ 1600 

0 

1800 

2000 

0 

\ 

ll 

r-- ~---~ 

< t:::. 

r---I-"'" 

~ 

~ 

... 6::::: . 

A ~ ;-

lllllt. 

-~ 

~ ~ 1-

-...~ -

\ ~ ~ 

~, 

J 

I 

I(_ t-.... 

~"""-!-

20 40 60 

CLAY CONTENT, 

IN PERCE~T OF 

DRY WEIGHT 

0 

l\ 

Ll 

r---r-1\. 

~~ ~ 

4~ 

~ -- ~ 

-~ L 

-~~ 

I' -r--.... 

r 

.v 

{_ 

... j"-......_ 

/~ 

~ 

.L 

1-'-~ 

~ 

40 80 

VOLUMETRIC 

SHRINKAGE, 

IN PERCENT OF 

DRY VOLUME 

120 

FIGURE 16.1.-0lay content and volumetric shrinkage of samples from core hole 19/17-22.11,2. 

Kettleman City area is plotted in figure 16.2, which 

shows that the decrease in volume in a sediment mass 

is proportional to the percentage of clay. AJO-percent 

increase in clay content causes an approximate increase 

of 20 percent in volumet:r:ic shrinkage. The relationship indicated by the trend line in figure 16.2 may be 

represented by the equation 

Vs=2.1(0-10), 

where Vs=volumetric shrinkage, in percent of dry 

volume; 

0 =clay content, In percent of dry weight. 

100~--~----~----~--~-----p----~--~ 

~ 20~--~ .. ._~-----+----~----~----~----1 

..J 

() 

0~--~----~---a----~--------~--~ 0 20 40 60 80 100 120 140 

VOLUMETRIC SHRINKAGE, IN PERCENT 

OF DRY VOLUME 

FIGURE 16.2.-Relation of volumetric shrinkage to clay content 

for samples from three core holes in the Los BanosKettleman City area, California . 

This relationship thus makes it possible to estimate the 

volumetric shrinkage by determining the clay content 

of samples of the sediments. 

REFERENCES 

Atterberg, A., 1911, Uber die physikalische Bodenuntersuchung, 

und Uber die Plastizitat der Tone: Internat. Mitteilungen 

fUr Bodenkunde, Band 1, Heft 1, p. 7-9, p. 10-43. 

Baver, L. D., 1948, Soil physics: 2d ed., New York, John Wiley 

and Sons, Inc., p. 101-124. 

Goldschmidt, V. M., 1926, Unders.Oekser over Lersedimenter: 

Beretning om Nordiske Jordbrugs forskeres Kongress i 

Osla: Nordisk Jordsbrugsforskning, 4-7, p. 434-445. 

Inter-Agency Committee on Land Subsidence in the San Joaquin 

Valley, 1958, Progress report on land subsidence investigations in the San Joaquin Valley, California, through 1957: 

Sacramento, Calif., 160 p., 45 pls. 

Poland, J. F., and Davis, G. H., 1956, Subsidence of the land 

surface in the Tulare-,Vasco (Delano) and Los BanosKettleman City area, San Joaquin Valley, California: Am. 

Geophys. Union Trans., v. 37, no. 3, p. 287-296. 

Russell, J. C., and Wehr, F .. M., 1928, The Atterberg consistency 

constants: Am. Soc. Agronomy Jour., v. 20, p. 354-372. 

Terzaghi, Karl, 1926, Simplified soil tests for subgrades and 

their physical significance : Public Roads, v. 7, p. 153-162. 

··' 

•• 
ARTICLE 17 B-45 

GEOMORPHOLOGY 

17. LOWER PLEISTOCENE PRAIRIE DIVIDE TILL, LARIMER COUNTY, COLORADO 

By D. V. HARRIS and R. K. FAHNESTOCK, Fort Collins, Colo. 

Work done in cooperation with the Colorado State University Geology Department 

A large. glacial deposit forms the divide between 

the North Fork of Rabbit Creek and the upper drainage of theN orth Fork of Cache la Poudre River in the 

Front Range of northern Colorado. It is located on 

the borders qf the Livermore and Home quadrangles 

in Sees. 5, 12, and 17, T. 10 N, R. 72 W, 30 miles northwest of Fort Collins (fig. 17.1). The deposit was first 

described by Ray (1938/ 1940) and by Bryan and 

Ray ( 1940). Other features probably of glacial origin 

are the Red Feather and Creedmore Lakes (fig. 17.1). 

1 Ray, L. L., 1938, Geomorphology and Quaternary chronology of 

northeastern Colorado : Harvard Univ. Ph. D. thesis. 

FIGURE 17.1.-Relief map showing location and geologic setting of the Prairie Divide Till of Ray (1938) and a similar glacial 

deposit (X). Horizontal lines delineate areas of sedimentary rocks; vertical lines indicate possible source areas of igneous 

marker rocks ; unlined areas are underlain by granite and schist of Precambrian age (after Lovering and Goddard, 1950) . 

The rectangle marks the area covered by figure 17.2. The major canyons cut since Prairie Divide time are those of the 

Cache la Poudre River and the Laramie River. 
B-46 GEOLOGICAL SURVEY RESEARCH 1962 

The sul.'face of the main body of this deposit is a 

high, flat, treeless prairie lying at an altitude of 7,900 

to 8,000 foot. A ridge extends 3 miles down valley from 

the dissected east edge of the main body of till (fig. 

17.2). The ridge was formed by streams that cut their 

valleys along the contact between the till and granite, 

leaving a ridge of till. In the broad preglacial valley 

shown in-figures 17.2 and 17.3, small patches of drift 

remain on the valley sides at an altitude as low as 

6,700 feet. Another large deposit occupies the tributary valley to the south. 

Figure 17.3 shows profiles of the Prairie Divide deposit and the North and Middle Fork valleys of Rabbit 

Creek. Location of these profiles is shown on figure 

17.2. Longitudinal profile A shows the high treeless 

prairie and the long ridge. B extends across the main 

valley and the till ridge. At 0, downvalley from the 

till deposits, the valley is broad in distinct contrast 

with the narrow, V-shaped valley of the Middle Fork 

of Rabbit Creek to the south, shown in profile D. 

Boulder till is exposed in road cuts and gully banks 

within the deposit. Many of the boulders are deeply 

weathered, but other boulders, apparently of the same 

rock type, are essentially unweathered. A few cobbles 

are altered to green plastic clay. The upper 8 to 18 

inches of the till is noncalcareous, but at many places 

a caliche zone is developed 2 to 3 feet below the surface. 

Most of the material in the deposit comes from areas 

of Precambrian rocks (mainly granitic and metamorphic rocks) shown in figure 17 .1. However, two rock 

types, felsite and red sandstone, indicate that the ice 

moved from the Cameron Pass area (fig. 17.1) 35 

miles northeast to Prairie Divide. According to John 

A. Campbell (oral communication) the only outcrops 

of the red sandstone (Chugwater) at higher elevations 

than the till occur about 2 miles north of Cameron 

Pass. The volcanic area near Cameron Pass is a possible source of the felsite, but more probably it was 

derived from small bodies of Tertiary intrusive rocks 

south of Red Feather Lakes, in direct line from Cameron Pass to Pairie Divide. 

The topography over which the ice traveled must 

have been radically different from the present topography (fig. 17.1) or from that of Wisconsin time when 

the canyons directed ice movement. If the canyon of 

the Cache la Poudre River, which is as much as 2,000 

feet deep, had existed at the time of the Prairie Divide 

deposition, it would have directed the flow of the ice to 

the east. In addition, the form of the present canyon 

would be similar to the valley of Lake Chelan (Willis, 

1903) because of extensive erosion by through-flowing 

ice. Prairie Divide would then be unlikely to contain 

thick, extensive glacial deposits. 

Prairie Divide Till fills a broad valley (fig. 17.3, 

profiles B and 0) cut below the Rocky ~1ountain surface formed during the Pliocene prior to the 1nain 

canyon -cutting cycle (fig. 17 .3, profile D) . From work 

elsewhere in the Southern Rocky Mountains, VanTuyl 

and Lovering (1935), Atwood (1937), Wahlstrom 

FIGURE 17.2.-Aerial mosaic of the Prairie Divide deposit. Most of the treeless 9-reas are covered by till. Letters refer to the 

sections shown on figure 17.3. Bar in center foreground represents a distance of about 1 mile. 

• 

1 
·~ 

,-

ARTICLE 17 B-47 

1ooo·-P\ A~ 7500'~ ~ ~ 

7000'~ B 0 6500'~ c 

A EXPLANATION 

8000' B - ~-~ 

~ LLLJ 

Till Bedrock 

7500' 

7000' 

0 1 MILE 

DATUM IS MEAN SEA LEVEL 

FIGURE 17.3.-Longitudin.al and transverse profiles of the Prairie Divide deposit and the North and Middle Fork Valleys 

of Rabbit Creek. Location of sections is shown on figure 17.2. 

(1947), Ives (1953), and Richmond (-1957) concluded 

that lower Pleistocene glaciers were icecaps rather than 

valley glaciers. The position of Prairie Divide Till 

with respect to its source area substantiates this interpretation. 

A deposit of bouldery material at least a square mile 

in area, and closely resembling the Prairie Divide Till, 

lies about 8 miles southeast of Prairie Divide at the edge 

of the Colorado Piedmont (fig. 17.1, X). This deposit, 

located on Lone Pine Creek, is tentatively correlated 

with the Prairie Divide deposit. If these 2 deposits 

are contemporaneous, this lobe of the ice sheet covered a large area and moved downslope t.o altitudes 

as low as 6,300 feet. 

Future work may establish age relationships between 

the Prn.irie Divide Till, the till at Lone Pine Creek, 

and the high pediment in the Colorado Piedmont. The 

fact thnt the Prairie Divide ice traveled at least 35 

miles suggests that farther south, where the high country lies within 20 miles of the mountain front, deposits 

of this ice sheet should be sought as far east as the 

mountain front and, in selected areas, even beyond. 

REFERENCES 

Atwood, W. W., Jr., 1937, Records of Pleistocene glaciers in the 

Medicine Bow and Park Ranges (Wyoming and Colorado) : 

Jour. Geology, v. 45, no. 2, p. 113-140. 

Bryan, Kirk, .and Ray, L. L., 1940, Geologic antiquity of the 

Lindenmeier site in Colorado : Smithsonian Misc. Colin., 

v. 99, no. 2, pub. 3554, 76 p. 

Ives, R. L., 1953, Anomalous glacial deposits in the C<>lorado 

Front Range area, Colorado: Am. Geophys. Union Trans., 

v. 34, no. 2, p. 22()-226. 

Lovering, T. S., and Goddard, E. N., 1950, Geology and ore 

deposits of the Front Range, Colorado: U.S. Geol. Survey 

Prof. Paper 223, 319 p. 

Ray, L. L., 1940, Glacill'.l chronology of the southem Rocky 

Mountains: Geol. Soc. America Bull., v. 51, no. 12, p. 1851-

1917. 

Richmond, G. l\f., 1957, Three pre-Wisconsin glacial stages in 

the Rocky Mountain region: Geol. Soc. America Bull, v. 68, 

no.2,p. 239-262. · 

Van Tuyl, F. M., and Lovering, T. S., 1935, Physiographic development of the Front Range: Geol. ·soc. America Bull., v. 46, 

no. 9, p. 1291-1350. 

'Vahlstrom, E. E., 1947, Cenozoic physiographic history of the 

Front Range, Colorado: Geol. Soc. America Bull., v. 58, 

no. 7, p. 551-572. 

Willis, Bailey, 1903, Contributions to the geology of Washington:· 

U.S. Geol. Survey Prof. Paper 19, p. 58-63, 81-83. 
B-48 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

18. LATE PLEISTOCENE AND RECENT EROSION AND ALLUVIATION IN PARTS OF THE COLORADO RIVER 

SYSTEM, ARIZONA AND UTAH 

By MAumeE E. CooLEY, Tucson, Ariz. 

Work done in cooperation with the Bureau of Indian Affairs 

Most valleys and canyons on the Colorado Plateau 

contain alluvium which ranges in thickness from 25 to 

200 feet. At least five cycles o£ downcutting and alluviation o£ Pleistocene age record the entrenchment o£ 

the streams in the Colorado River basin. The total 

cutting that occurred during Quaternary time was 

between 800 and 1,500 feet and that during late Pleistocene and Recent time was between 100 and 300 feet. 

The Quaternary events are listed on figure 18.1. 

Period 

and 

epach 

Etosional or 

depositional 

event 

ifi~~ .. c\:•u~ll~'~:.~ ;--

Abundance of 

associated 

eolian 

dePOsits 

Fluvial 

conditions 

Deposition by scour· 

and·fill action; runoff 

concant,cated in 

channels and as 

~-~· llleet floodina 

~3 (rou(lhly . ----- - iiit'Pcisitio'; bY slcnw:- -

correlative with moving water, and in 

Naha formation Rare swamps; runoff 

~ of Hack, 1942) spread out on 

Associated fossil 

and cultural dePOsits 

and Christian 

calender years 

1925 An(IIO· 

American 

firm and 

1905 ranch and 

Navajo and 

1880 Paiute 

utilization 

1850 

Navajo 11nd 

Paiute 

Pueblo IV 

~ !Z t------~------ _ _fl~e!~-·--- ffi ~ Erosion 1 ' 1--c_o_m_mo_n-+ __ R_a.;...pid_ru_no_ff--+ 

~ ~ t--U-ni-t 4-(-ro-u(l-hly.J DePOsition by slow· 

1300 

Pueb~lll 

llOO 

Pueblo II 

o correlative with Rare to llld fltst·movina Pueblo 1 upper part of common watllr; runoff partly 

Tseai formation concentrated in Basketmaker 111 

~-!f!!c~~~2~- ------ -~~~e~s _____ ~soo-----4 

1--

w 

Erosion 

~---------

Unit 5 (rou(lhly 

correlative with 

lower part of 

Tse11i formation 

of Hack, 1942) 

Erosion 

~ Glaciofluvial, 

o alluvial, and 

0 terrace dePOsits, 

:n end the 

~ Jeddito Formation 

1:L. of Hack, 1942 

Probably 

rare to 

common 

Same as unit 4 

~A.D. 1 

1 chipped stone 

toql 

1:~~~iin-to ---------- ~ ~bout iooo lf.c. au~tndant Rapid runoff "" 5000-6000 B.C. 

DePOsition by 

fast-.and slow· 

movin11 water 

Remains of 

tarae mammals 

FIGURE 18.1.-Chart showing late Pleistocene and Recent erosional and depositional events in parts of the Colorado River 

system. 

Most alluvial sediments in the valleys and canyons 

are indicated to be o£ late Pleistocene age by the presence o£ fossils o£ large mammals near the Little Colorado River (Reiche, 1937; Hack, 1942; Lance, 1960) 

and by the relations o£ the deposits and stream terraces 

to the glaciofluvial deposits in the nearby mountains. 

The fossils were found only in: the Jeddito Formation 

and in the terrace deposits along the Little Colorado 

River. Geologic mapping indicates that glaciofluvial 

sediments described by Sharp ( 1942) on San Francisco 

Mountain extend downstream and grade into terrace 

deposits along Deadman Wash and the Little Colorado · 

River. The lower gravel terraces along the San Juan 

and Animas Rivers can be traced into the glacial-outwash deposits in the San Juan Mountains (Atwood 

and Mather, 1932, p. 131). 

Most deposits o£ late Pleistocene age in the Colorado 

River system consist predominantly o£ sand and gravel, 

although muddy and sandy deposits were laid down by 

some streams. The type o£ deposit is related to the 

strea~ regimen and to periglacial and glacial activity 

within the drainage area. Streams that have a sizeable 

part o£ their headwater areas above 7,500 feet, such as 

the Colorado, San Juan, Little Colorado, and Escalante 

Rivers, and Deadman Wash, tended in Pleistocene time 

to deposit gravelly sediments much coarser than those 

laid down in Recent time. Streams that head below 

7,500 feet, such as ,Jeddito Wash and Castle Creek, 

deposited a relatively small amount of gravel, and the 

gravel, at least locally, is finer than that in the Recent 

alluvium. 

The Pleistocene deposits form terraces, anq. possibly 

are preserved beneath Recent alluvium, along the Colorado, Little Colorado, and San Juan Rivers and along 

the lower parts of the larger tributary streams (figs. 

18.2A, B). In the upstream reaches o£ the tributaries, 

post-Pleistocene cutting exposed only the upper part 

o£ the Pleistocene deposits (figs. 18.20, D). 

Recent time is represented by 5 alluvial units and by 

2 prominent and 2 secondary cycles o£ erosion and 

arroyo £ormation (fig. 18.1). 

The age o£ Recent events has been interpreted £rom 

associated cultural material, which ranges from Basketmaker III , to the present land utilization, or since 

about A.D. 500 (R. H. Thompson, oral communication, 

1961). However, nearly all the cultural deposits that 

can be used £or dating are related to or are embedded 

within unit 4 and are only indirectly related to the 

other depositional and erosional events o£ Recent time. 

lTnit 4 forms the bulk of the Recent alluvium in the 

arroyo walls o£ most washes o£ the Colorado Plateau. 

The lower parts of the exposures usually contain crossbedded sand and gravel beds which intertongue 

laterally with and grade upward into sandy silt and 

silty sand layers. Buried soils containing carbona-

.... , 

.-

'J 

·""fl 

). 
-t 

160' 

120' 

80' 

40' 

r 

Navajo 

Sandstone 

, 

Channel of 

Colorado River 

0'~---------------------------------------------L 

160' 

140' 

120' 

100' 

80' 

60' 

40' 

20' 

A. Colorado River in Glen Canyon, Ariz. and Utah 

Rocks of 

Mesaverde 

Group 

I I 

\ 

Unit I s- II ~/ -2/ -~ 

\ Unit 1 .......... _...._ / ~' 1 

\""----_.../ ~ / 

' e / '-.. Pleistoc.e(' / ........ ____ / .,... 

I 

I 

I 

I 

o•._ __________________________________________ ~ 

D. Escalante River 15 miles upstream from Escalante, Utah 

160' 

120' 

80' 

40' 

Navajo Sandstone Navajo Sandstone 

0' F.~;:-;::=:-;-::=---:~:::--:.:::~~~___1 F. Lake Canyon, Utah, 5 

miles upstream from 

mouth 

G. Lake Canyon, Utah, 2 

miles upstream from 

mouth 

~ 

120' 

100' 

80' 

60' 

40' 

20' 

0' 

50' 

40' 

~ 

Channel of little 

Colorado River 

,~, 

Umt ·' 4~\. ,, Units 1-3 1 / 

Late Pleistocene(?)-\-.._ "~'------~ I Chinle 

alluvium \ / Formation 

-"'" 

\..._// 

--~~==~~------~ B. Little Colorado River near Cameron, Ariz. 

200' 

160' 

120' 

80' 

40' 

I 

Tsegi I 

Fm I 

(unit 4)1 

I 

'/·-/.._ ... / 

Unit 1 --

Navajo Sandstone 

o·~·------------------------------~ E. laguna Creek in Marsh Pass, Ariz. 

(modified from Hack, 1942, fig. 46) 

~ .. ~~",;;IV Living cottonwood '"' . .!.lj;\'·.~· t "i~' ~r( , ,4 o;\ ree Q~~i~_,.J 11-f-,- li-'""''"li.''- ·-!: 

30' ,n. .... 

20' Unit 4 

10' 

0'~----------------~---------------------------L H. Moenkopi Wash near Cameron, Ariz. 

180' 

120' 

60' 

·r-

\ \ .,A~f I ~ \ Unit 4\-\ \ I $'0 / 

\ (?) ,,. '..:-.-~o': ..... / 

Mancos \ Unitl ---- Mancos 

Shale ' Jeddito Formation Shale 

0

, 1 , (Pleistocene) .... 1 

C. Jeddito Wash, Ariz. (modified from Hack, 1942, fig. 30) 

Monticello0 I N 

1 ~} ~~ .... 

nnnnanui)~ 

(' 'iS{ - \ 0.1 E Kayenta · .. 

'O ~( -c I ~..d I ~: 'r . .,Q . ~~ '-~ t-t~k.~... 0 1' -E ~~·· : H· wa.sh. ~-· . ..:' ~~ Cameron ~~{ 

NEW MEXICC?~'!> 

/y 

Ship~ i RIVER 

v-s> 

:1 ~ tv ziL 1 

~:::i II ~.>- ~~ \S' 

B-r.- ,./ 

..to.&Jc;; ~~··· -~~ -n.fl. T' _::r-· . .., ~ . ~"l b'l'";.·-·· \.. 7 . / 

"':, ... F. San '>~q;, .. Je~~~'\:c 

Pt..,tJ,, I 

. tf2.il Window Rock~ ,.,U 

I 

25 O I ~~"', .. ra~flscci·, t !:/" 

Flagstaff ... ~z, , ..... 

INDEX MAP SHOWING LINES OF PROFILES 

FIGURE 18.2.-Profiles showing late Pleistocene and Recent alluvial and terrace deposits in parts of the Colorado River drainage system, Arizona and Utah. 

The sediments of Recent age consist in descending order of units 1, 2, 3 (Naha Formation of Hack, 1942), and units 4 and 5 (Tsegi Formation of Hack, 

1942). The sediments of late Pleistocene age consist of glacio:fluvial, alluvial, and terrace deposits, and the Jeddito Formation of Hack, 1942. 

> 

1-1 

~ 

a 

t'4 

t"J 

.... 

00 

td 

~ 
B.-50 GEOLOGICAL SURVEY RESEARCH 19 6 2 

ceous material and very thin mud beds are scattered 

throughout the unit. The upper few feet of the unit 

usually contains considerable interbedded eolian 

material. 

Unit 5 (fig. 18.2A), the oldest alluvial unit of 

Recent age, is beneath unit 4 in small exposures in 

Glen Canyon and possibly in other areas. It is lithologically similar to unit 4, although it is more firmly 

cemented. In some places a channeled erosion surface 

separates units 5 and 4, and in others their contact 

appears to be gradational. Evidence is insufficient at 

present to determine whether the channeled surfaces 

represent a regional or a local event. 

Deposition of unit 4 was terminated by an erosional 

episode which may have started as early as A.D. 1100; 

erosion seems to have predominated during the A.D. 

1200's, although in a few drainages no evidence of erosion during this time span was found. Stripping seems 

to have predominated during the earlier part of this 

erosional cycle, and deep channeli1_1g and arroyo cutting 

were restricted to the later part. In areas away from 

the deep channels, the erosion surface had slight relief; 

the channels were cut from 10 to 20 feet below the general level of this surface and are about two-thirds as 

deep and one-fifth as wide as the present arroyos formed 

in the same area. 

Terraces were formed on unit 4 deposits during- erosion in the A.D. 1100's and 1200's along the Colorado 

River along most reaches of the Little Colorado and 

San Juan Rivers and along parts of tributary drainages, such as Harris Wash, J eddito Wash, Laguna 

Creek, and Lake Canyon (fig. 18.2A, B, 0, E, and G). 

In most places along the tributary streams the overlying sediments of unit 3 were deposited over the entire 

valley floor (fig. 18.2F, H). 

Unit 3 contains a relatively large amount of carbonaceous material. It is composed mainly of very thin 

to thin-bedded sediments ranging from mud to silty 

sand. Gravel, prominent crossbedding features, and 

wind-deposited material are uncommon. The unit contains buried soils, and usually a prominent soil is the 

uppermost bed. In· many exposures unit 3 is represented only by this soil zone. 

Units 5, 4, and 3 are probably roughly correlative 

with the Tsegi and N aha Formations defined by flack 

(1942) (fig. 18.20, E). Hack (1942, p. 51) noted that 

locally in Jeddito Valley, the Tsegi is separated by 

an erosion surface into a lower part and an upper part, 

which probably correlate with units 5 and 4, respectively. The N aha probably correlates with unit 3. 

However, the correlations are tentative and the names 

N aha and Tsegi have not been extended beyond the 

areas where they were originally defined. 

Events associated with the present episode of arroyo 

cutting abruptly terminated the deposition of unit 3. 

The earliest event was deposition of a thin mantle of 

sand and gravel (early unit 2). This was followed by 

the main cutting of the arroyos which occurred generally between about A.D. 1850 and 1900 (Bryan, 1925; 

Gregory and Moore, 1931, p. 143). Locally, deposits of 

late unit 2 were laid down within the confines of the 

arroyo, partly burying living cottonwood trees (figs. 

18.2D, H). These deposits form low alluvial terraces 

whose heights approximate· those of high floods (fig. 

18.2H). Most arroyos have widened since the main 

cutting, and at the present time some may be aggrading 

in a few places in the Defiance uplift-Chuska Mountains 

area. 

The alluvial units were deposited under different 

fluvial conditions. Sediments of unit 3 were laid down 

by sluggish streams, and gravels in units 1, 2, and 4 

by more vigorous streams (fig 18.1). The division of 

late Quaternary time into three broad periods of alluviation separated by periods of erosion (Bryan, 1940) 

can be recognized in many canyons and valleys, 

although the number, magnitude, and duration of the 

erosional and depositional events differ from drainage 

to drainage and along reaches of the same drainage. 

REFERENCES 

Atwood, W. W., and Mather, K. F., 1932, Physiography and 

Quaternary geology of the San Juan Mountai~s, Colorado: 

U.S. Geol. Survey Prof. Paper 146. 

Bryan, Kirk, 1925, Date of channel trenching in the arid Southwest : Science, v. 62, p. 338--344. · 

--1940, Erosion in the valleys of Southwest: New Mexico 

Quart., v. 10, p. 227-~2. 

Gregory, H. E., and Moore, R. C., 1931, The Kaiparowits region, 

a geographic and geologic reconnaissance in parts of Utah 

and Arizona: U.S. Geol. Survey Prof. Paper 164. 

Hack, .J. T., 1942, The changing physical environment of the 

Hopi Indians of Arizona: Peabody 1.\iuseum Papers, v. 35, 

no. 1. 

Lance, J. F., 1960, Stratigraphic and structural position of 

Cenozoic fossil localities in Arizona : · Arizona Geol. Soc. 

Digest, v. 3, p. 155-160. 

Reiche, Parry, 1937, Quaternary deformation in the Cameron 

district of the Plateau province: Am. Jour. Sci., 5th ser., 

v. 24, p. 128-138. 

Sharp, R. P., 1942, Multiple Pleistocene glaciation on San 

Francisco Mountain, Arizona: Jour. Geology, v. 50, p. 481-

503. 
..,.· 

ARTICLE 19 B-51 

19. RELATIONS OF ALLUVIAL-FAN SIZE AND SLOPE TO DRAINAGE-BASIN SIZE AND LITHOLOGY IN 

WESTERN FRESNO COUNTY, CALIFORNIA 

By WILLIAM B. BuLL, Sacramento, Calif. 

Work done in oooperation with the California Department of Water Resources 

Along the western border of the San Joaquin Valley 

in western Fresno County, Calif., the relations of the 

area and slope of uJluvi~~l fnns to the area and lithology 

of their drainage bn.sins have basic and applied significance. The relations illustrate some fundamental 

concepts of fan morphology, and they demonstrate 

the effect of drainage-bn.sin lithology on the areal 

extent and thickness of deposits susceptible to nea.rsurface subsidence when wetted. Near-surface subsidence is a phen01nenon that seriously hinders engineering and ~tgricultural operations on cedain alluvial 

fans. 

The fan slope used in computing quantitative relations is the avernge overall slope from the apex of the 

fan to the outer margin, where the fan conlesces with 

another fan or with the deposits of rivers in the trough 

of the San Joaquin Valley. Radial profiles drawn near 

the middle of the fans from n.pex to foot were used to 

help determine the lower end of the slope to be measured. The fan boundaries were determined by contour 

maps, aerial photographs, and tests of the gypsum 

content of 400 core-hole samples. The gypsum content 

of fan deposits whose drainage basins are underlain 

predomimtntly by clay-rich rocks is about five times 

that of fnn deposits whose drainage basins are underlain predominantly by sandstone. Lithology of the 

bedrock in the drainage basins of the area has been 

described in detail by the writer (Bull, 1961a). 

The fans studied range in size from 0.4 to 260 square 

miles. Figure 19.1A shows that all the fans derived 

from drn.inage basins underlain mainly by mudstone 

and shale and half of the fans derived from drainage 

basins underlain mainly by sandstone are larger than 

their drn.irmge basins. The plotted points scatter moderately about straight lines described by the equations 

shown on the figure. On the logarithmic graph the 

slopes of the lines (0.88) are equal, showing that fan 

area increttses in about the snJne exponential manner as 

drainage-basin area incren.ses, despite appreciable differences in lithology. The coefficients of the equations 

(1.3 and 2.4) show that, on the nverage, fans derived 

from drainage basins eha.racterized mainly by mudstone and shale are roughly twice as large as the fans 

derived from drainage basins . of comparable size 

characterized mainly by sandstone. 

The fans studied range in overall slope from 0.0035 

( 0° 12') to 0.029 ( 1° 40'). Figure 19.1B shows that 

the overall fan slope decre~tSes with an increase in 

drainage-basin size. In drainage basins of comparable 

size, all but the smallest fans of mudstone and shale 

drainage basi11s slope more steeply than fans of sandstone basins. Tl~e apexes of .fans of mudstone and 

shale drainage basins are, on the average, 520 feet 

above the trough of the San Joaquin Valley, whereas 

the apexes of fans of sandstone drainage basins have 

an average height of 400 feet above _the valley trough. 

These relations indicate that, for drainage areas of 

comparable size, fans derived from mudstone and shale 

are not only larger, as shown by figure 19.1A, but also 

thicker than fans derived fr01n sandstone. Presuma.bly, these differences may be attributed largely to the 

greater erodibility of the mudstone and shale. 

· The relation of fan area to fan slope for the fans 

studied is shown in figure 19.10. In general, fan slope 

decreases with increasing fan area. The fans derived 

from mudstone and shale drainage basins are: ( 1) 

steeper than fans of similar area that are derived from 

sandstone drainage basins, and ( 2) larger than fans of 

similar slope from sandstone basins. 

Irrigation has producec;l more than 10 feet of nearsurface subsidence on certain alluvial fans in western 

Fresno County and about 125 square miles has subsided 

or probably would subside if irrigated. This settling 

of the land surface is caused by the compaction of 

moisture-deficient clay-rich deposits by the overburden 

load as the clay bond supporting the voids is weakened 

by water percoiating through the deposits for the first 

time (Bull, 1961b). The magnitude of the subsidence 

is controlled by the thickness of the moisture-deficient 

deposits .and by such factors as overburden load and 

amount and type of clay . 
B-52 , 

.....J 

.....J 

<( 

a:: 

LJ.J '> 

(/) 

LJ.J 

.....J 

~ 

LJ.J 

a:: 

<( 

:::> 

0' 

(/) 

z 

u.. 

~ 

<i 

LJ.J 

a:: 

<( 

z 

<( 

LL... 

100 

10 

1.0 

GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

• Drainage basin underlain by 48 to 86 

percent mudstone and shale 

0 Drainage basin underlain by 58 

~o 68 percent sandstone 

0.3~--~--~~~~~----~~~~~~----~~--~~~U---~--~~~~LU 

0.1 1.0 10 100 1000 

DRAINAGE-BASIN AREA, A0 , IN SQUARE MILES 

0.003~----~~~~~~--~~~~~~~--~~~~~~~--~~~~~~ 

0.1 1.0 10 100 1000 

u.. 

V) 0.03 LJ.J 

Q_ 

0 

.....J 

(/) 

DRAINAGE-BASIN AREA, A0 , IN SQUARE MILES 

z 

<( 0.01~--------------~--------------~~~---------=~~--------------~ LL... 

.....J 

.....J 

<( 

a:: 

LJ.J 

> 

00.003L---~~_J~~~L---~~~_L~~L---~~~_L~~L---~~~_L~~ 

0.1 1.0 10 100 1000 

FAN AREA, A F• IN SQUARE MILES 

FIGURE 19.1.-Relations of fan area and slope to drainage-basin area and lithology in. western Fresno County. . .. ; 

'11 
~· 

.., 

ARTICLE 20 B-53 

The subsiding ·fans are associated with drainage 

basins that are underlain mainly by mudstone and 

shale. Subsiding fans are thicker and almost twice as 

large as nonsubsiding fn.ns derived from basins of comparable size. Thus the drainage-basin lithology directly affects both the potential areal extent and the 

potential amount of near-surface subsidence. 

REFERENCES 

Bull, ,V. B., 196la, Alluvial fans and near-surface subsidence 

in western Fresno County, California: U.S. Geol. Survey 

open-file report, 264 p. 

--1961b, Causes and mechanics of near-surface subsidence 

in western Fresno County, California: Art. 77 in U.S. Geol. 

Survey Prof. Paper 424-B, p. B187-B189. 

20. RECENT GROWTH OF HALEMAUMAU, KILAUEA VOLCANO, HAW All 

By DoNALD H. RICHTER, JAMES G. MooRE, and RoBERT T. HAUGEN, Hawaiian Volcano Observatory, 

Hawaii, and National Park Service, Washington, D.C. 

Work aone in cooperation with the U.S. National Park Service 

Halemaumau is a nearly circular crater indenting the 

relatively flat floor of the summit caldera of Kilauea 

Volcano on the island of Hawaii (fig. 2().1). In historic time Halemaumau, or the general southwest area 

of the caldera it presently occupies, has been the principal site of IGlauea's summit activity and is generally 

regarded ns overlying .the main magma conduit leading 

0 q , , .... 

CONTQ.It INTf.RVAL. I.OOOFtU 

----l--19' 

''6' ,,,. 

I 

FIGURE 20.1.-Map of the island of Hawaii showing the Kilauea 

caldera and the inner crater of Halemaumau . 

to the summit. Presently 550 feet deep and averaging 

3,400 feet in diameter, Halemaumau continues to enlarge year after year by slides and rockfall off its precipitous and highly fractured walls. This paper, 

based on mapping and measurement of cracks arou11d 

Halemaumau's rim, is a study of the crater's growth 

through the period 1928 to 1961. 

In the 140 years that has elapsed since Kilauea was 

first visited, Halemaumau has had a complex history. 

Between 1823 and 1890, a period marked by four great 

collapses involving almost the entire caldera floor, the 

general area of present-day Halemaumau contained a 

number of active lakes of lava that intermittently filled, 

overflowed, and drained away~ About 1905, Halemaumau became identifiable as a single crater-the famous 

"fire-pit" of Kilauea-and for almost 20 years there 

was a dazzling display as liquid lava circulated in a 

lake 1,500 feet in diameter. In 1924 the lava lake suddenly drained away, and a series of violent steam 

eruptions, resulting from the penetration of ground 

water into the heated conduits beneath the caldera, 

blasted from Halemaumau. These eruptions and concurrent collapse left Halemaumau more than 1,300 feet 

deep and over 3,000 feet in diameter, essentially its 

present wi~th. Since 1924, 11 separate eruptions (the 

last in July 1961) have added to the fill in the bottom of 

the crater. 

During the enlargement of Halemaumau in 1924 a 

number of peripheral cracks developed around the 

crater, leaving the rim unstable and subject to landslides. The 'subsequent gradual enlargement of the 

crater has been largely controlled by these cracks, which 

bound the successive slide blocks. The cracks are nearly 
B-54 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

vertical at the surface, but they probably dip steeply 

toward the crater at depth. On the nortlnvest rim, 

where the crater outline is chordlike, rather than arcuate, the cracks continue far back of the edge and tend 

to complete the pit's circular outline.. 

Figure 20.2, an outline map of Hale.maumau, shows 

the progressive enlargement of the crater during 3 consecutive intervals (1928-45, 1945-62, 1952-61) in the 

400 0 

33-year period between 1928 and 1961. The. 1928 outline is based on a topographic survey made. by R. M. 

Wilson ( J aggar, 1930) ; the 1945 outline on an aerial 

photomosaic; and the 1952 and 1961 outlines on planetable mapping and triangulation by G. A. Macdonald, 

W. E. Benson, and the authors. The. precision of 

matching each successively older outline with the. 1961 

outline decreases because. of the. removal of re.CognizN 

400 800 FEET 

---Rim of crater wall (Nov.l961) 

Base of crater wall 

•' .· .. ··:·:·.· . 3 

. ·.:.: Yi-.:>·\~f.:·<:': :\':'i\u~iiF;~: . 

FIGURE 20.2.-0utline map of Halemaumau showing major peripheral cracks and rim recession due to landsliding between 

1928 and 1961. Recession is divided into three periods: 1, 1928-45; 2, 1945-52; and 3, 1952-61. Positions of measured 

lines plotted on figure 20.3 is shown by lines 1-5. 
ARTICLE 20 B-55 

n.ble features by sliding. Since 1928 the crater opening 

on the cnJdera floor has grown in area from 942,000 to 

998,000 sqmtre yards, an increase of 56,000 square yards 

or uJmost ()percent (see table below). The average anlnutl growth for the 3 time intervals varies from 1,300 

to 2,200 square yards per year. Average· annual growth 

throughout the entire 33-year period is 1,700 square 

yards per ye~tr, equivalent to a rate of rin1 recession 

nveraging 1.5 feet per year. However, as is shown in 

.figure 20.2, the growth pattern has been neither consistent nor regular, and some 15 percent of the original 

1928 r.itn still remains standing. Greatest attrition has 

occurred on the east, northeast, south, and northwest 

parts of the crater, where the rin1 has retreated as much 

as 150 feet in the last 33 years. 

lnc1·ease in area of lialemaurnau d~tring the period 1928-61. 

Area Increase Rate Rate of rim 

Year (square yards) (square yards) (square yards recession (feet 

per year) per year) 

1928 ___________ 942,000 

22, 000 1, 300 1. 1 1945 ___________ 964,000 

14, 000 2,000 1.7 

1952 _____ ------ 978,000 

20, 000 2, 200 2. 0 

1961_ ____ ------ 998, 000 

33-year aver- n.ge ________ ---------- ---------- 1, 700 1.5 

For rnn,ny years the width of individual cracks 

around I-Ialemaumau has been periodically measured 

in an attempt to correlate the opening of cracks with 

volcanic activity and, in the interest of public safety, 

to ascertain which areas along the crater rim are likely 

to collapse. The pattern of crack development determined from these individual'measurements, however, is 

not consistent. Most of the cracks, if they are not lost 

in collapse, ha,ve opened irregularly since the measurements beg:n.n, with unaccountable periods of no change 

and even of measurable closing. l\1oreover, some 

cracks have shown a marked increase in opening preceding an eruption (Macdonald, 1955) while others 

ha.ve shown an increase following eruption (Jaggar, 

1930). 

In the belief that measurements along lines perpendicular to the crater rim and spanning a number of 

peripheral cracks might be more definitive, measurements were begun in the fall of 1959 along three lines 

normn.l to the rim (fig. 20.2, lines 1, 2, 3). The 3 lines, 

which average about 80 feet in length were measured 

from before the 1959 sumtnit eruption until after the 

1960 flank eruption. In l\1ay 1960 the rim-end pins of 

two lines fell into the crater on large slides. The 

dramatic increase in the length of all lines, culminating 

in the slides of May, is shown graphically in figure 20.3. 

Plotted on the same base are the eruption periods and 

the east-west component of ground tilting at Uwekahuna, 1 mile northwest of the center of Halemaumau. 

The tilt plot is a measure of the slight, deformation, 

measured in radians, of the· earth's surface in the 

IGlauea summit region caused by the accumulation and 

movement of magma within the volcano from Ap~·il 

1959 to November 1961. In response to the gradual 

accumulation of magma, pi·eceding and during periods 

of summit activity, the summit region tumesces. 

Detumescence occurs when magma from within the 

volcano drains away into the rift zones, often producing a flank eruption (Eaton and Murata, 1960). 

Clearly, the accelerated rate of crack growth (fig. 20.3), 

began with the great detumescence of the dome in January 1960; there was no measurable effect on the length 

of the lines during the tumescence in October, November, and December 1959. Additional measurements 

along two new lines (fig. 20.2, lines 4, 5) during the 

1960-61 period of tumescence and detumescence of 

IGlauea's dome are also shown on figure 20.3. As 

during the earlier observations, the relatively rapid 

tumescence, from the end of 1960 to September 1961, 

was not accompanied by a marked change in the length 

of the lines, but during the brief detumescence, in September 1961, the length of the lines increased measurably as rim cracks enlarged. 

Although slides and rockfalls off the wall of Halemaumau are almost daily phenomena, the long-line 

measurements on the crater's rim reported here indicate 

that the opening of peripheral cracks, and hence growth 

of the crater, accelerates during detumescence of the 

volcanic dome. The reason for this correlation of ac-

. celerated crack opening with beginning of detumescence 

is not fully understood. Quite likely the withdrawal 

of magma from beneath the summit area, resulting in 

the removal of vertical support, may also substantially 

reduce the lateral support at the base of the crater and 

initiate crack opening. This appeared to be the case 

in the detumescence of ,January-March 1960 when 

almost the entire floor of Halema.umau dropped 100 to 

350 feet. In the detumescence of September 1961, however, there was no evident physical change in the bottom 

of the crater. Strong, local earthqmtke activity accompanying detumescence is another factor that may play 

an important role in the development of new cracks and 

the widening of existent cracks. 
B-56 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

1959 1960 1961 

MONTH~M~~~~J~~A~!~S~~O~!~N~!~D~~~J~F~!~M~!~A~!~M~!~~J~~A~!~S~!-O~!~N~~D~~~J~~F~~M~!~A~!~M~!~J~!~J~!~A~-S~!~O~!~N~ 

'<t 

'o 

X 

Ill 

c; 

0 

:0 

0 

a:: 

C\J 

0 

0 

0 

~ 

0 

A. ERUPTIONS: 

S, summit; F, flank 

8. GROUND TILTING AT 

UWEKAHUNA: 

1 

West (tumescence) 

East (detumescence) 

C CHANGE IN LENGTH 

OF MEASURED LINES: 

1 

Decrease 

Increase 

F s s s F 

- ·- - I 

4 

--- 5 

FIGURE 20.3.-Graph showing relations during period May 1959-November 1961 of: A, Kilauea eruptions; B, ground tilt at 

Uwekahuna in the Kilauea caldera area; and 0, changes, in the length of lines normal to the rim of Halemaumau. 

REFERENCES 

Eaton, J.P., and Murata, K. J., 1960, How volcanoes grow: 

Science, v. 132, p. 925-938. 

Jaggar, T. A. 1930, Rim cracks and crater slides: Volcano Letter 

283, p. 1-3. 

Macdonald, G. A., 195G, Hawaiian volcanoes during 1952: U.S. 

Geol. Survey Bull. 1021-B, p. 1-108. 

PALEONTOLOGY 

21. MARGINAL SEA OF MIDDLE EOCENE AGE IN NEW JERSEY 

By STEPHEN M. HERRICK, Atlanta, Ga.1 

Perfectly preserved specimens of llf arginulina vacavillensis (Hanna) and associated small Foraminifera 

in a test well in Camden County, N.J., suggest the presence of a sea in New Jersey in middle Eocene time 

similar to that of the Gulf coast. The nearest pre viously reported occurrence of this species was in a well 

in Liberty County, Ga. (Herrick, 1961a, p. 260). 

Previous to this, llf aTginulina vacavillensis had been 

1 Ruth Todd, U.S. Geological Survey, furnished the following significant identifications : Pseudouvigerina wilcoxensis and Ohiloguembelin(t 

martini at a depth of 360 to 362 feet; Globigerina boweri at 370 to 372 

feet; and Globorotalia bullbrooki and Truncatulinoides roheri at 380 to 

382 feet. 

1 
ARTICLE 21 B-57 

reported from western Florida (Herrick, 1961b, 

p. D239.) As this fossil was originally described from 

California (Ilanna, 1923) its discovery in New Jersey 

(Jig. 21.1) proves the distribution of this species in all 

the coastal plains of North America. 

EXPLANATION PENNSYLVANIA 

• __ ,__-~MD. -----·----- Known occurrence 

I I I~' v I ., 

!' c, 

A 

New discovery 

/,-

: VIRGINIA 

L -------- ----------- T 

,f' NORTH CAROLINA 

TENNESSEE ,.../' 

. l , ... ---""---, ------T·-- --r' ', I '• 

I ""\ \ '•"\.\ c:~~~~A \ \ ALABAMA \ GEORGIA ' 

) 

, 

\ 

I 

.----- ---"\.__-----~: 0 

I 

100 

I 

i 

200 MILES I 

FIOU!Ull 21.1 .. -Geogrnphic distribution of Mar,qinnlina vacavillcnsi.'! along the Atlnntic and eastern Gulf coasts. New discovery is in U.S. Geological Survey New Brooklyn Park 2 

well, Camden County, N.J. 

Sediments containing the Foraminifera found inN ew 

Jersey were probably deposited .in· a marginal moderately deep sea-on the order of 80 fathoms (vVermund, 

1961, .P· 1682-which ftuctua.ted at .intervals during 

rniddle Eocene time. In spite of these fluctuations the 

sea persisted .in New Jersey long enough for the deposition of approximately 140 feet of abundantly glauconitic sands, sandy clays, and marls, all of which 

are here regarded as t:he Manasquan Formation. These 

deposits bear a strong lithologic and faunal similarity 

to the 'Veches Greensand Member of the Mount Selman 

Formation of Texas and a strong faunal similarity to 

the Cook ~fountain Formation of Louisiana (Howe, 

1939). · In addition to Ill a'rginulina vacavillensis, many 

fonuniniferal species previously reported from the Cook 

~fountain Formation also are present in this microfauna (fig. 21.2). 

Str~t I Lithology umt J ~---r-r--4---f-----+- 0 FEET 

Age 

r-_ ,__ ____ ----_ f----_-_-_-_ 

,:::: f-=-=-=-=-::=- ·B -{Bulimina buchiana S Planulina depressa 

~ 5 ~==~===~= Cibicides concentricus 

~ < ! H~-~~~~~ ~ _-_-_-_-_-_ 

~ -:::=-:::=-=-=r-200 ~ ~-=~-=-=-=- ~ -{Karreriella mauricensis 

~ 1---r-,....-b~~~-:-1 Centtobulimina eximia 

~{{}.~/? :\{~:}\ Cibicides tallahattensis 

.)'.'.y_,:,.,:_ ·-.:_::·.: 

:/:.:\-}::}/ \\ J Rob1tlus inornatus ·\:(((.} ~y; :-::. ~ LRobulus alato-limbatus 

,:::: Wt::=;::/.:: . r Marginulina conrathi 

Q) ·B --I..Eponides beaberlene 

E S. -{Spiroplectammina znpoten.sis .f 5 Non_ion micrus 

·ca ~ ---.._r Robulus pseudovortex 

S ; l..Marginulina cf. variabilis ::s 

cr r-300- Abundant glauconite ~ ,:::: 

~ 

::I!S 

---Marginulina vacavillensis 

---Eponides m~xicanus 

-1 Spiroplectammina wilcoxensis 

Eponides dor.fi 

~~---+."'"T'T'T'TTTT"'"TT'T'1 Valvulineria scrobiculata 

,.. 

~ ><' a e Globorotalia wilcoxensis 0 ::s 

~~ ~i; ...:1!3: ~--­ '-':Jl 

EXPLANATION 

~ 

~ 

- D 

Sand Micaceous Glauconitic Glauconitic No sample 

lignitic clay sand, shelly calcareous 

clay 

FIGuRE 21.2-Log prepared from samvles from the upper part 

of U.S. Geological Survey New Brooklyn Park 2 well, Camden 

County, N.J. 
B-58 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

Ecologic studies of living ·organisms suggest that 

similar fossil species lived under similar environmental 

conditions. One may conclude from the evidence at 

hand, therefore, that a sea, similar to that known to 

have occupied the Gulf coast during middle Eocene 

time, also existed in coastal Georgia and New Jersey 

and probably in unreported intervening areas (the 

Carolinas and Virginia) . 

. As far as the writer is aware this paper constitutes 

the first recognition of middle Eocene Foraminifera 

this far north in the Atlantic Coastal Plain. Spangler 

and Peterson ( 1950, p. 61) in a paper on the geology 

of the coastal plain in the central Atlantic States, 

consider the Manasquan Formation to be early Eocene 

(Wilcox) in age. On the basis of a few molluscan fossils, a vertebrate fossil, a.nd a crab's claw, Miller (1956, 

p. 733) concludes that "the Manasquan Formation is 

mid-Eocene Claiborne in age." The age of the Manasquan has been considered by Loeblich and Tappan 

( 1957, p. 1113) to be earliest Eocene (Ypresian). On 

the basis of previous work and information presented 

in this article, the age of the Manasquan is considered 

to be early and middle Eocene. 

REFERENCES 

Hanna, G. D., 1923, Some Eocene Foraminifera near Vacaville, 

California: California Univ. Devt. Geol. Sci. Bull., v. 14, 

no. 9, p. 319-328. 

Herrick, S.M., 1961a, Well Logs of the Coastal Plain of Georgia: 

Georgia Dept. Mines, Mining, and Geology Bull. 70, 462 p. 

---1961b, A stratigraphically significant association of 

smaller Foraminifera from western Florida: Art. 376 in 

U.S. Geol. Survey Prof. Paper 424-D, P. D239 . 

Howe, H. V., 1939, Louisana Cook Mountain IDocene Foraminifera: Louisiana State Dept. Conserv., Geol. Bull. 14, 122 p. 

Loeblic.h, A. R., .Jr., and Tappan, Helen, 1957, Correla•tion of the 

Gulf and Atlantic Coastal Plain, Paleocene and lo.wer 

Eocene formations by means of planktonic Foraminifera : 

.Jour. Paleontology, v. 31, no. 6, p. 1109-1137. 

Miller, H. "r., Jr., 1956, Correlation of Paleocene and. Eocene 

formations and Cretaceous-Paleocene boundary in New 

.Jersey: Am. Assoc. Petroleum Geologists Bull., v. 40, no. 

4, p. 722-736. 

Spangler, W. G., and Peterson, .J. J., 1950, Geology of Atlantic 

Coastal Plain in New Jersey, Delaware, Maryland, and 

Virginia ; Am. Assoc. Petroleum Geologists Bull., v. 34, no. 

1, 99 p. 

Wermund, E. G., 1961, Glauconite in early Tertiary sediments of 

Gulf Coastal Province: Am. Assoc. Petroleum Geologists 

Bull., v. 45, no. 10, p. 1667-1696. 

22. RECENT DISCOVERIES OF THE CRETACEOUS AMMONITE HARESICERAS AND THEIR STRATIGRAPHIC 

SIGNIFICANCE 

By WILLIAM A. CoBBAN, GLENN R. ScoTT, and JAMES R. GILL, Denver, Colo. 

The Late Cretaceous ammonite H aresicera8 was found 

in the Niobrara Formation near Pueblo, Colo., in October 1961. Owing to its. association with the well 

known ScaJJhites hippocrepis (DeKay) of early Campanian age, H aresicera8 has been considered a guide 

fossil to that Cretaceous stage (Cobban and Reeside, 

1952, p. 1019, and correlation chart). The discovery 

of H aresiceras near Pueblo thus provides evidence of 

a long-suspected early Campania.n age for the upper 

part of the Niobrara of the central Great Plains ( J eletzky, 1955). The purpose of this paper is to discus~ 

the stratigraphic implications of this discovery and to 

bring up to date the known records of occurrences of 

H aresiceras. 

Haresicera8 was proposed by Reeside (1927, p. 17) to 

include ammonites that have compressed whorls, narrow mp.bilicus, flat venter. bordered by two rows of very 

small nodes, and subparallel flanks crossed by weak 

sigmoidal ribs. Reeside described three species: H. 

placentifonne from the Telegraph Creek Formation of 

Park County, Wyo., H. natroneme from the Cody Shale 

of Natrona County, Wyo., and H. fi~1wri from the 

Mancos Shale of Emery County, Utah. 

Haresiceras was first found by C. J. Hares in 1916. 

The genus is now known from 23 Geological Survey 

Mesozoic localities in the western. interior of the conterminous United States, 18 of which have been recorded in earlier reports. Reeside (1927, distribution 

table) listed 13 occurrences in Utah, Colorado, Wyoming, South Dakota, and Montana from rocks now assigned to the Mancos Shale, Cody Shale, Telegraph 

Creek Formation, and Gammon Ferruginous Member 

of the Pierre Shale. Five other· occurrences in the 

Cody Shale of central "\V'yoming have been recorded 

by Yenne and Pipiringos (1954), Hose (1955, p. 96), 

and l{eefer and Troyer ( 1956). 

.4 I 

.... 
• 

ARTICLE 22 B-59 

New occurrences of Il(//f'esioeras are listed below with 

their Geological Survey ~fesozoic catalog numbers: 

231,.77. NE1;4NE% sec. 13, T. 9 S., R. 61 E., Carter 

County, Mont. From gray 1 imestone concretions in 

Gammon Ferruginous Member of Pierre Shale about 

130 feet below Groat Sandstone Bed and 460 feet 

above top of Niobrara Formation. 11 aresice'ras placent'ifor·m,e. 

.D1847. T'hree miles north of Bear Butte in the NElJr 

NEl4. sec. 6, T. () N., R. 6 E., Meade County, S.Dak. 

From m.arlstone lens in lower part of Gammon Ferruginous Me1nber of Pierre Shale. Il a'resiceras nat'l·one'n8e. 

D181,..9. About 3.5 miles south of Alkali Creek in the 

N'V14. sec. 9, T. 4 N., R. 8 E., ~1eade County, S. Dak. 

From nmrlstone lens 50 feet above base of Gammon 

Ferrug.inous Meinbet· of Pierre Shale. 11 aresiceras 

nat'I'O'nense. 

D2827. Four miles north of Boulder in the S'V%SElj1 

sec. 1, T. 1 N., R. 71 ,V., Boulder County, Colo. 

From 28 feet below top of Niobrara Forrnation (base 

of upper yellowish-orange chalky limestone unit of 

Smoky }[ill Shale Member). Ilaresiceras natronen . .se ( ~) 

JJ3266. One mile east of Apishapa River on small 

spur at base of mesa. in the NE1;4SvV1;4N,V1;4 sec. 

23, T. 23 S., R. 59 ,V., Otero County, Colo. From 84 

feet below top of Niobrara Formation (platy yellowish-gray chalky limestone about 70 feet below upper 

yellowish-ontnge chalky 1 imestone unit of Smoky Hill 

Shale Member). H(u·esice?YlS plaoent'ifor"lne. 

The last :four localities are of exceptional interest in 

that they are the first records of 11 a1··esioe'ras in South 

Dakota east of the Black Fillls and in Colorado east of 

the Front Range. The two collections from east of the 

Black }[ills were made by Gill fr01n grayish-orangeweathering madstone in a partly calcareous shale unit 

assigned by the writers to the Gammon Ferruginous 

~feinbet· o:f the Pierre Shale but clearly transitional into 

Niobrara .I ithology. The fossils are chiefly impressions 

but include a few well-preserved uncrushed septate 

coils. 8caJJldtes aq'ttilaensis Reeside and a fine-ribbed 

:form of 80(lJJhites hiJJpom·epi,s (Del(ay) are associated 

with the Hm··esice?Yl8 at the Bear Butte -locality 

(D1847). The two collections from the Front Range 

area in Colorado were made by Scott frmn rocks of 

unquestioned Niobrara lithology. The collection from 

loeali.ty D2827 near Boulder consists of an impression 

of part of a very large specimen that does not show the 

venter. The strongly ribbed flanks suggest assignment 

to 11. 'na,t?··one'nse. The collection from Otero County 

(D326()) consists of rather poor impressions of 15 

weakly ribbed specimens assigned to fl. JJlacentiform~. 

629660-62-5 

These are associated with impressions of fragments of 

scaphites thn,t could be 8. hippoc'l'eJJis. 

H(f,'resiceras placentiforme a1i.d fl. natronense have 

not been found together. The holotype of H. placentiforme came from the Elk Basin Sandstone Member of 

the Telegraph Creek Formation in the Elk Basin oil 

field along the boundary of Montana and Wyoming 

where it was associated with coarse-ribbed forms of 

8ca1JhUe~ hizJpocrepis. The type of H. natronense 

came from the Cody Shale 200 feet below the Shannon 

Sandstone Me1nber in the Salt Creek oil field in N atrona County, vVyo. Fossil collections made subsequently by Gill at that locality show that a level 200 

feet below the Shannon Sandstone Member is near the 

top of the range of S. hippocrepis and that the late form 

of this scaphite is characterized by fine ribbing. The 

Eagle Sandstone of central and south-central Montana 

contains this type of scaphite. A preliminary study 

of the collectionR of If aresioeras from all localities in 

the western interior region shows that fl. plaoentijm"''ne 

is older than If. natronense and is associated w~th a 

coarser form of S. hizJpocrepis. Both coarse- and 

fine-ribbed forms of 8. hippocreJJis were figured by 

Grossouvre (1893, pl. 32, figs. 2, 3a, 3b; pl. 35, figs. 

6a-c; pl. 37, figs. 3a, 3b) and assigned to the Campanian. 

The Telegraph Creek Fonnation at Elk Basin overlies undifferentiated "Niobrara and Carlile Shales" 

(Dobbin and others, 1945). Farther east on the northwest flank of the Powder River Basin the Telegraph 

Creek is treated as a member of the Cody Shale and 

overlies the Niobrara Shale Member of the Cody which 

is in part calcareous (Richards, 1955, p. 55). The 

occurrence of H aresioeras JJlacentiforme in the Telegraph Creek Formation at Elk Basin and in the Niobrara Formation near Pueblo, Colo., shows that the 

top of the Niobrara rises in time in a southeasterly direction. That the Eagle Sandstone, which overlies 

the Telegraph Creek Formation, is also a time equivalent to the upper part of the Niobrara Formation is 

suggested by the occurrence of H. natronense associated 

with fine-ribbed forms of 8cazJhites hippocrepis in 

Niobrara and Pierre transition rocks on the east side 

of the Black Hills uplift and by the presence of what 

appears to be II. nat1·onense within the Niobrara Formation in Colorado. 

REFERENCES 

Cobban, W. A.; and Reeside, J. B., .Jr., 1952, Correlation of the 

Cretaceous formations of the Western Interior of the 

United States : Geol. Soc. America Bull., v. 63, no. 10, 

p. 1011-1044. 

Dobbin, C. E., and others, 1945, Geologic and structure map of 

the Elk Basin oil and gas field and vicinity, Park Oounty, 
B-60 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

~Wyoming, and Carbon County, Montana: U.S. Geol. Survey General Mineral Resources Map. 

Grossouvre, A. de, 1893, Recherches sur Ia Craie Superieure, 

pt. 2, Paleontologie, Les ammonites de la Craie Snpedeure: 

Mem. Carte geol. France, 264 p. [1894]. 

Hose, R. K., 1955, Geology of the Crazy Woman Creek area, 

.Johnson County, "W"yoming: U.S. Geol. Survey Bull. 102·7-B, 

p. 33-118. 

. Jeletzl\:y, J. A., 1955, Belemnitella p1·aeourrso'l·, probably from 

the Niobrara of Kansas, and some stratigraphic implications: .Tour. Paleontology, v. 29, no. 5, p. 876-885. 

Keefer, ,V. R., and Troyer, l\L L., 1956, Stratigraphy of the 

Upper Cretaceous and lower Tertiary rocks of the Shotgun 

Butte area, Fremont County, 'Vyoming: U.S. Geol. Survey 

Oil and Gas Inv. Chart OC-56. 

Reeside, J. B., Jr., 1927, The cephalopods of the Eagle Sandr 

stone and related formations in the 'Vestern Interior of 

the United States: U.S. Geol. Survey Prof. Paper 151, 

p. 1-87. 

Richards, P. 'V., 1955, Geology of the Bighorn Canyon-Hardin 

area, Montana and 'Vyoming: U.S. Geol. Survey Bull. 

1062, p. 1-93 . 

Yenne, K. A., and Pipiringos, G. N., 1954, Stratigraphic sections of Cody Shale and younger Cretaceous and Paleocene 

rocks in the 'Vind River Basin, Fremont County, 'Vyoming: 

U.S. Geol. Survey Oil and Gas I1iv. Chart OC-49. 

23. TRIASSIC FOSSILS FROM THE SOUTHERN KLAMATH MOUNTAINS, CALIFORNIA 

By N. J. SrLBERLING and W. P. IRWIN, Menlo Park, Calif. 

Fossils recently collected near the mutual boundary 

of Tehama, Trinity, and Shasta Counties in northwestern California confirm the Late Triassic age of 

some of the eugeosynclina1 rocks included by Irwin 

( 1960, fig. 3, p. 20-26) in the "Western Paleozoic and 

Triassic Belt" of the Klamath Mountains. Heretofore, 

the presence of Triassic rocks in this belt was indicated 

by its continuance northward into exposures of the 

Applegate Group, which was assigned a Late(?) Triassic age by Wells, Hotz, and Cater(1949, p. 3, 4), and 

by several small, poorly preserved specimens of the 

Triassic ammonite A rcestes in one of several collections 

made by Diller ( 1903, p. 344-356) in the southern 

Klamath Mountains. The new collection of fossils 

described here provides a relatively precise age determination for one locality in this large structurally and 

stratigraphically complex belt, and it demonstrates 

that well-preserved biologically and stratigraphically 

useful faunas can be found in these rocks, which for the 

most p~rt have not yet received detailed study. 

In May and October 1961, the writers attempted to 

relocate Diller's ammonite locality near White Rock, 

a prominent limestone outcrop on the divide between 

the drainages of the Sacramento and Trinity Rivers 

about 5 miles northwest of North Yolla Bolly Mountain. At the approximate location given by Diller a 

concentration of fossiliferous limestone float was found 

in an area underlain mostly by mafic volcanic rocks 

and thin-bedded radiolarian chert. Its localized occurrence near the crest of the drainage divide and its 

proximity to outcrops of limestone interstratified with 

volcanic rocks and chert indicates that this :fossiliferous 

float was derived more or less in place fron1 a .. sma..ll 

limestone lens which may have been only several inches 

thick and a few feet long. 

The fauna obtained from this locality (USGS Mesozoic locality M1140; see locality list at end of paper) 

is surprisingly diverse and well. preserved, although 

the cephalopods are mainly small immature specimens 

which cannot be identified positively as to species. Of 

foremost age significance are the ammonites, which 

include: 

Olionitites cf. 0. angulo8U8 (Mojsisovics) 

Lecanites sp. 

Styrites cf. S. vermetus (Dittmar) 

J uvavites sp. 

Arcestes sp. 

Oladiscites cf. 0. pusillus (Mojsisovics) 

11/egaphyllites cf.llf. jarbas (Munster) 

Placites cf. P. plaeoides (Mojsisovics) 

Mo.fsvarites cf. M. eugyrus (Mojsisovics) 

Also present are shell fragments of the pelecypod 

H alobia with ribbing like that of H. arztstriaca Mojsisovics; pectenid, pteriid, nuculid, and other pelecypods; 

indeterminate gastropods; orthoconic nautiloids; rhynchonellid, spiriferid, terebratulid, and lingulid brachiopods; and crinoid columnals. The ammonites for the 

most part belong to long-ranging genera including 

some that first appear in the upper Middle Triassic and 

others that range through the Upper Triassic. The 

association of ammonite genera, however, is distinctive 

and unlike that .of any other known fauna from the 

-· II 
-.. 

I~ 

... I 

ARTICLE 23 B-61 

Triassic of N oith America. The genera and species of 

ammonites represented are n1ost like those of the middle 

1\:a.rn in.n fauna. of the 1'nwhyce1Yt8 aonoides zone, 

described by ~iojsisovics (1893, p. 796-798; 1902, p. 

336-337) from the I-Ia.llstatt region of Austria. The 

arrunonites :from near 'Vhite H.ock thus represent a 

sornewlmt older part of the J(arni~ul than the rich late 

1\:a.rnia.n a.mmonite fauna, n1onographed by J. P. Smith 

(1927), fr01n the so-caJled I-Iosselkus Limestone about 

60 miles to the northeast in the easternmost J\]amath 

~fountains. 

'1'he fauna, from the limestone float at. loca..lit.y M1140 

:is markedly different from that of nearby larger masses 

of limestone, some of which have an outcrop area of 

several acres or more. These large limestone bodies, 

such as 'Vl1ite H.ock (USGS ~iesozoic localities ~11217 

a.nd ~11218) and a conspicuous limestone about 5 1niles 

to the northwest on the divide between I-Iayfork and 

Prospect Creeks (USGS ~1esozoic locality ~11216), consist of massive pure somewhat recrystallized organic 

detrital limestone bounded on all sides by volcanic 

rocks. Hecognizaole fossils are scarce, though fragInentary scleractinian corals, hydrozoans, bryozoa, and 

calcareous a.lgae were found in both limestorie bodies. 

Some of these fossils are indicative of an early Mesozoi~" 

age, but they provide no basis for detailed age 

assignment. 

LOCALITIES CITED 

[Alllocnlltles In southem Klamath MountainH>, Calif .. ] 

USGS MeRozoic loc. l\11.140. Near boundary between Trinity 

nnd Tehnma Counties about % mile west of "'hite Rock 

limestone. Float hlo<::ks of limestone found together on 

south side of ~aernmento Ynlley-Trinity RiYer drainage 

divide just downhill from low saddle on crest. Center of 

JjJ% sec. 1!), T. 28 N., H. 10 W., Dul.Jakelln l\ft. 15-min. quad. 

Collected. by N .. T. Silberling, D. h .)one:;, nnd W. P. Irwin, 

:\lay lHGl. [Possibly the same as loc. 705 of Diller (1003, 

p. 3H).] 

GSGS :\Iesozok loc. Ml2Hl. 'l'rinity County. Conspicuous 

limestone mass on north side near <::rest of ridge between 

Hayfork and Prospect Creeks. NEl4NEl4 sec. 4, ~r. 28 

N., R. 11 W. Dubakella Mt. 1G-min. quad. Collected by 

N .. J. Silherling and W. P. Irwin, Odober J!.)(il. [Apvroximately the smne as locs. 703 and 706 of Diller (1903, 

11· 346).] 

USGS Mesozoic: loc. l\f1217. Near boundary between Trinity 

and 'l.'ehama Counties. Isolated limestone mass about ¥10 

mile north of main 'Vhite Rock limestone outcrop area. 

On north side near erest of Sacramento Valley-Trinity 

River drainage divide. Center of ·w14 sec. 20, T. 28 N., 

R. 10 "\V. Dnhakella l\H. Hi-min, (JUHd. Colleded by N .. J. 

Silherling all(l W. P. Irwin, Odober 1001. 

USGS Mesozoic loe. M1218. Near boundary between 'l'rinity 

and Tehama Counties. Northeast end of main 'Vhite Rock 

limestone outcro11 area. On south side near crest of 

Sacramento Valley-'l'rinity RiYer drainage divide. Center 

of W% sec. 20, '1'. 28 N., R. 10 W. Dubakella Mt. 15-min. 

quad. Colleeted by N .. J. Silberling and W. P. Irwin, 

October 19tll. [Approximately the snrne as loc. 704 of 

Diller ( 1!)03, v. 344) . ] 

REFERENCES 

Diller, .J. S., 1903, Klamath Moutain seetion. Am . .Jour. Sci., ser. 

4, v. Hi, p. 342-3()2. 

Irwin, ,V. P., 1060, Geologic reeonnaissance of the northern 

Coast Hanges and Klamath Mountains, California: California DiY. Mines Bull. 179, 80 p. 

Mojsisovics, Ji}dmund von, 1803, Die Cephalor,oden der Hallstiitter Kalke: Ahh. geol. Reichsanst. Wien, Band 6, 

Hiilfte 2, 83G p., l)lS. 71-200. 

---1902, Die Cephalopoden der Halstiitter Kalke. Suppl.-

Heft: Abh. Geol. Heiehsnnst. 'Vieu, Band 6, Hiilfte 1, p. 17f,_ 

3G6, 23 pls. 

Smith, .J. P., 11)27, lJp1•er 'l~rinsgie mnrine invertebrate faunas 

of North America; U.S. Geol. Survey l'rof. Paper 141, 262 

p., 121 l)lS. 

\Vell~, F. G., Hotz, P. K, and Cater, :E'. "r., .Jr., 1!)49, Preliminary 

description of the geology of the Kerby quadrangle, Oregon; 

Oregon Dept. Geology amll\fineral· Industries Bull. 40, 23 p. 
B-62 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

GEOPHYSICS 

24. THERMAL REGIME IN THE RAISED DELTA OF CENTRUM S0, NORTHEAST GREENLAND 

By DANIEL B. l(RINSLEY, vVashington, D.C. 

Work done in COOJJet·ation with Air Force Camb·ddge Besr.arch Labm·atot·ies 

Centrum Sy> (lake), lat soo 10' N. and long 22° vV., 

occupies a northeast-oriented glacial valley that has 

been cut 2,:300 feet below an extensive plateau. The 

lake is 12 miles long and 2.5 miles wide near its midpoint (fig. 24.1) ; the surface of the lake is :328 feet 

above sea level. The principal tribut:u·ies, Saefaxi Elv 

and Graeselven 1 (rivers), originate at the margin of 

the Greenland Ice Cap 25 miles ''"est and southwest of 

the lake. The outlet into Lower Saefaxi Elv, at the 

east end of the lake, is 20 miles from the sea at Hekla 

Sun d. 

1 Provh;ional name. 

The bedrock surrounding the western two-thirds of 

the la.ke is part of a thick series of banded clark limestones and lighter dolomitic beds of Ordovician and 

Silurian age (Centrum Limestone). The beds eli p 

gently eastward but are tightly folded locally. East 

of the Centrum Limestone along an approximately 

· north strike, older dolomitic. rocks, most of which are 

of Precambrian age, have been thrust over the Silurian 

limestones (Frankl, E., 1954). 

Glacial and glac.iolacustrine deposits of variable 

thickness mantle the lower slopes and the high plate~tu 

above the lake. Rec.essional moraines on the plateau are 

~ 

~ 

0 

PRINCIPAL BODIES OF WATER 

GLACIERS AND ICECAPS 

RECESSIONAL MORAINES AND 

RELATED MARGINAL CHANNELS 

5 10 15 MILES 

00' 

FIGURE 24.1.-Map of the Centrum S~ area. 

'j 
:4·. 

i~l 

..... 

J 

\ 

ARTICLE 24 B-63 

convex downvaJley and, along with associated marginal 

cha.nnels which have been cut in the steep valley slQipes, 

have been traced westward to the margin of the Greenla.nd Ice Cap (I\.rinsley, 19()1). V\Tell-preserved lake 

tel.'races, as much us 256 feet above the present lake surface, overlie coarse morainal materials and grade into 

extensive lacustrine deposits of fine sandy red silt a.nd 

coai.'Ser ice-rafted materials at the outlet. of the .lake. 

Random shallow corings along the lake bottom. consist 

uniformly of fine red silt. 

Centrum 80 freezes over in late September, and the 

ice breaks up in ,June; the lake is generally ice free by 

late .July. There are no meteorological records for the 

winter months; the nearest weather station at Nord, 

127 miles northeast, has a considerably wetter climate 

so that extrapohttion is not reliable. Meteorological 

data collected during the field season of 1960, together 

with the reports of previous summer and winter visitors, suggest tha;t the ·Centrum 80 area is an arctic 

desert with a total annual precipitation of 4 to 6 inches. 

In 1960, mean daily air temperatures ranged from 

-20.0°C to 5.0°C in ~fay; -6°C to 13.0°C in June, 

and from 12.0°C to 14.0°C in July. The prevailing 

wind was from the west in May and June and from the 

/:····' 

southwest in .July. ~{ean wind speed was about 8 miles 

per hour fi·om ~{ay through J·uly. On .June 9, a windstorm from the north produced gusts of as much as 42 

miles per hour. 

A deltaic deposit formed by the coalescence of Snefaxi 

Elv and Graeselven, when the lake level was 24 feet 

higher tha.n at present., now occupies a triangular area 

between the tributaries at the west end of the lake (fig. 

24.2). This raised delta, the a,pex of which is oriented 

toward the east, is 1.2 miles long, m1d 1,500 feet wide at 

its midpoint. Nea,r the east end of the delta, the foreset 

beds dip 28° NE.; at the center the dip is 4° NE. The 

delta is composed of alternating layers of sand and sand 

with pebbles and granules of limestone and crystalline 

materials. l'he composition and structure of the delta 

indicate that it was constructed primarily from crystalline and sedimentary rocks carried by Graeselven from 

areas near the margin of the icecap (fig. 24.1). 

The deltaic deposits are covered with as much as 4 

inches of silty (eolian) sand containing dreikanter 

pebbles and granules. Neither clay sizes nor particles 

larger than a pebble have been observed in the delta. 

Low-center polygons ranging from 3 to 22 fee;t in diam-

,.///;.~~:·/ 0 300 600 900 1200 1500 FEET 

CONTOUR INTERVAL 2 FEET 

~.' 

r-: 

DATUM IS MEAN SEA LEVEL 

FIGURE 24.2.-Generalized map of the raised delta of Centrum S~. 
B-64 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

eter with borders rising as much as 4.7 inches are best 

developed in the east half of the delta. The west half 

is characterized by blowouts as nuich as ao inches deep, 

sand mounds 1 foot high, covered with low arctic plants, 

and wide gullies, most of which drain into Saefaxi 

Elv. Some blowouts are filled with water during the 

tTune thaw. 

Currently the delta is eroded by gullying during the 

snowmelt period (,June 1-15) and by lateral stream 

cutting from Saefaxi Elv and Graeselven. · Deflation 

during the snow-free period (,June 15 to September 15) 

is an important mechanism for surficial erosion. 

In May, the frost table was approximately 12 inches 

below the surface at the center of the delta and dipped 

gently to 16 inches below the surface at the northeast 

edge of the delta. On May 19, a hole 60 inches deep 

was dril1ed in the center of a. polygon which was located 300 feet frmn the east end of the delta (fig. 24.2). 

A thermocouple cable was lowered into the hole and 

17.SC15.0°-

w 12.5°-

c 

~ 10.0°- C> 

~ 

·Z 

w 7.50-

u 

en 

w 5.0°- w 

~ 

C) 

w 2.5°- c 

z 

.. 0.0°-

w 

~ 

:;:) 

~ -2.50-

w 

0.. -s.oo- ~ w 

..... -7~0-

·10.0°-

·~ ~ ~ 

thermocouples were placed 60, 36, 22.5, 20.5,- and 2 

inches below the surface; one thermocouple was installed 4 inches above the surface. At the time of the 

installation, the frost table was approximately 12 inches 

below the surface, but the thermal regime was disrupted 

by the drilling and the frost table was lowered locally 

as much as 4 inches within a 2-day period. The disruption of the thermal regime abated during the second 

week in .June, approximately 3 weeks after the installation (fig. 24.3). 

The following general chara.cteristics of the thermal 

regime may be inferred from the observed data., 

although the period of observa.tion wa.s relatively short 

and the disturbed ground did not have sufficient time 

for complete thermal stabilization. Ground tempera.-

tures start to rise as soon as the insulating snow cover 

has been removed ( about ~{a,y 15). Sublimation appears to be fa.r more important in snow removal than 

m.elting, consequently there is little downward tra.ns-

"""' ~ ~ 

EXPLANATION 

MEAN DAILY AIR TEMPERATURE 

-22.5 

GROUND TEMPERATURE 

NUMBER SHOWS POSITION OF THERMOCOUPLE ABOVE ( +) OR BELOW 

l-) GROUND SURFACE, IN INCHES 

-12.5°- ~ ~ ~ ~ ~ 

25 31 5 10 15 20 25 30 5 10 15 20 25 

MAY I JUNE I JULY 

FIGURE 24.3.-Air and ground temperatures in the raised delta of Centrum Sri. 

-~ l 

··, 
-( 

ARTICLE 25 B-65 

mission of heat :from melt water during this period. 

The rnnxirnum .increase in ground temperatures occurs 

between the last week in l\fay and the second week in 

.Tuly. After rn.id-,July the ground temperatures continue to rise slowly even though the air temperatures 

:fa.ll sha.rp.ly. The frost ta.ble on July 25 wus 30 inches 

below the surface at the thermocouple cable site. The 

fla.tten.i ng· o:f the ground-tem.pera.tnre curves during 

late .Tuly (fig. 24.3) suggests tha.t the permafrost table 

is probably a.t a. depth of 40 inches. Consequently, the 

active l~tyer is approximately 40 inches thick. 

REFERENCES 

Fdinkl, K, 1!>f4, Vorlnufige Mitteilung uber die. Geologie von 

Kronprins Christians Land : Meddelelser om Grjllnland, bd. 

116, ur. 2. 

Krinsley, D. B., 1961, Late Pleistocene glaciation in Northeast 

Greenhmd; Geology of the Arctic: Toronto, Toronto Univ. 

Press, v. 2, p. 747-751. 

~· 

25. MAGNETIC ANOMALIES AND ULTRAMAFIC ROCK IN NORTHERN CALIFORNIA 

By WILLIAl\f P. InwiN and GoRDON D. BATH, Menlo Park, Calif. 

Work done in cooperation with the California Di.vision of Mines and Geology 

Large positive ma.gnetic anomalies are shown by 

aerial traverses across the northern Coast Ranges, 

Great Valley, and I\Ja.math Mounta.ins of California. 

Seven r~connaissa.nce aeromagnetic traverses shown as 

line 13-13' through Ji-ll' (fig. 25.1) were flown by 

R. '"· Bromery in 1954 in conjunction with a geologic 

reeonnaissance (Irwin, 1960). Line A-A' is the western pnrt of a traverse flown from Denver, Colo., to Pt. 

Reyes, Cali:f. (Balsley, 1953). The area of contoured 

anomalies in the Great Valley (fig. 25.1) was flown 

dur.ing the period 1951 to 1954 (Grantz and Zietz, 1960). 

In both the northern Coast Ranges and J(la.math 

l\1ountn.ins the large positive anomalies are chiefly over 

~treas of ultramafic rock (fig. 25.1), and nearly all 

samples of ultramafic rock that were collected are 

strongly magnetic. Thus, the ultramafic rocks are 

thought to cause the principal anomalies. 

In t-.he southern part of the I\Jamath l\1ountains the 

linear bodies of ultrama.fic rocks generally reflect the 

prev:tiling northwesterly lithic and structural grain. 

The la.J'gest exposure of ultramafic rock, however, is an 

irregular area in the east-centra.l part of the province, 

crossed n.t its south end by traverse line F'-F' and 

slightly beyond :it-s north end by line G-G'. This large 

itTegu'lnr area is interpreted to be tl~e exposed crest of 

~t great, broadly arched, sheetlike mass of ultramafic 

n.nd gabbroic rock. Positive magnetic anomalies along 

traverse lines F'-F' and G-G' :u·e greatest in the general 

vicinity o:f this ultramafic nmss. Along line E-E', the 

m'uximurn high of the broad anomaly lies well east of 

the ensternrnost linear mass of ultrama·fic rock in the 

southern part of the Klamath ~1ountains. However, 

this seeming departure from the general pattern of 

positional correlation of magnetic anomalies and ultramafic rocks might be explained by the fact that this 

ultramafic mass is a sill that clips eastward, and thus the 

magnetic anomaly ma.y reflect a sheetlike extension of 

the sill at depth. 

The principal body of ultramafic rock in the northern 

Coast Ranges, exposed along the westen1 border of the 

Great Valley, separates rocks of the shelf and slope 

facies of late Mesozoic age on the east from chiefly 

eugeosynclinal rocks of late Mesozoic age on the west. 

It has a total length of more than 110 1niles from where 

it is crossed by traverse line A-A' to beyond line 0-0', 

although in the southern part it is discontinuous at 

many places owing to faulting. Large positive magnetic anomalies are shown along traverse lines A-A', 

13-B', and 0-0' where the lines cross this body of ultramafic rocks. These anomalies are on the west limb of 

the broad and generally stronger Great Valley anomaly. 

The Great Valley anomaly trends along nearly the 

entire length of the Great Valley for more than 300 

miles. Jenny (1932) reported that it extended along 

the valley from Red Bluff in the north through Stockton 

to Bakersfield in the south. Only the northern part of 

the Great Va1ley anomaly is shown on figure 25.1, indicated by the contoured are~t (Grantz and Zietz, 1960) 

and by the profiles along lines A-A' and B-B'. 

The Great Valley is underlain by a thick section of 

mildly deformed strata of late l\1esozoic and Cenozoic 

age, and along the anomaly the depth to .the basement 
B-66 

40"00' 

[00 GAMMAS 

VERTICAL SCALE OF 

MAGNETIC PROFILES 

25 

GEOLOGICAL SUR~EY RESEARCH 1 9 6 2 

122"00' 

0 25 MILES 

\ 

\ 

\ 

\ 

\ 

\ 

\ 

+ 

+ 

\ 

\ 

\ 

\ 

\ 

FIGURE 25.1.-Map of northern California showing aerial traverse lines A-A' through H-H', and outline of 

geologic provinces. Ultramafic rock·s are shown as black areas. Aeromagnetic profiles, with regional 

gradient (U.S. Coast and Geodetic Survey, 1955) removed, are plotted along the traverse lines. Line A-A' 

after Balsley (1953). Lines B-B' through H-H' observed and prepared under ·supervision of R. ,V. 

Bromery and J. R. Henderson. Contoured anomalies from Grantz and Zietz (1960). Traverse lines are 

not shown for the area of contoured anomalies. Contour interval 100 gammas. 

~) 

·~· 
+ 

ARTICLE 26 B-67 

complex has been established by drilling to range frorn 

approximate:Iy 1 to 3 1niles: Little is known regarding 

th.e kind of basement rock cored by drilling. Data 

a.vailable for 10 holes drilled along or near the crest 

of the anomaly, chiefly near Sutter Buttes, show the 

cored bn,sement rock to be chiefly intrusive rocks of 

interrnediate composition; 1 core was gabbro, and 1 

about 50 miles south of Sutter Buttes was ultramafic. 

Ultramafic rock buried at considerable depth along 

the lengt-h of the valley ma,y be the ca,use of the Great 

Valley anomaly. This relation is suggested chiefly by 

t·.he fact that the large anomalies are principally over 

a.reas oJ ultramaJic rock where the causative rocks are 

exposed. According to Grttntz and Zietz ( 1960), 

the rod:s producing the Great Valley anomaly at•e buried 

nhont: !) to 10 miles. but sharper, superimpo~;ed anomalies yield 

clepths that approximate the base of the Mesozoic and Tertiary 

sedimentnry rodu::. Becnuse they are magnetic and very large, 

the rock n1nsses which produee the broad magnetic highs are 

thought to be igneous. 

The ultramnJic rock, assuming that to be the cttuse of 

the Great Valley anomaly, must lie chiefly below a considerable thickness of basen1ent rock in addition to the 

late Mesozoic n.nd Cenozoic strata, judging from the 

difference between the known depth to basement and 

the depth to the anomaly-producing rock estimated by 

Grantz and Zietz (1960). J..JOcally, however, the ultramafic rock is part of the basement complex ~1t or near 

the interface of the basement and overlying strata., as 

shown by at least one well core, and thus might also 

account for the sharp local anomalies superimposed on 

the broad Great Valley anmnaly. 

REFERENCES 

Balsley, J. R., 1953, Total-intensity aeromagnetic profile from 

Denver, Colo. to Point Reyes, Calif.: U.S. Geol. Survey 

open-file report. 

Grantz, Arthur, and Zietz, Isidore, 19HO, Possible significance 

of broad magnetic highs over belts of moderately deformed 

sedim~ntary rocks in Alaska and California: Art. 158 in 

U.S. Geol. Survey Prof. PaJ)er 400-B, p. B342-B347. 

Irwin, 'V. P., 1960, Geologic reconnaissance of the northern 

Coast Ranges and Klamath Mountains, California: California Div. Mines Bull. 179, 80 p. 

.Jenny, ,V, P., 1932, Magnetic vector study of regional and local 

geologic structure in principal oil states: Am. Assoc. Petroleum Geologists Bull., v. 16, p. 1171-1203. 

U.S. Coast and Geodetic Survey, 1955, Total intensity chart of 

the United States: U.S. Coast and Geod. Survey, chart no. 

3077. 

MINERALOGY, GEOCHEMISTRY, AND PETROLOGY 

26. VANADIUM-RICH GARNET FROM LAGUNA, NEW MEXICO 

By RoBERT H. MoENCH, Denver, Colo. 

Wm·k (lone on behalf of the U.S. AtoHI-ic En.wgy 001nm,ission 

Vanadium-rich garnet has been identified as a constituent of it metamorphosed uranium-vanadium deposit in the Laguna mining district, about 15 miles west 

of Albuquerque, N. :Mex. The garnet occurs in one of 

several small deposits :in the Sandy uran:imn mine, about 

4 miles southeast of the village of Laguna. 

The presence of vanadium in ga.rnet was previously 

reported by Doelter ( 1916), who classed V20 3 as a rare 

component of calcium garnet and reported 0.09 and 0.24 

perc~nt V20a in 2 chemical analyses. According to his 

f.ormuln, (CaaV2Si:~Ot2) trivalent vanadium substitutes 

for aluminum and trivalent iron in the. calcium garnet 

series. ~1ore recently, Ba.dalov (1951) described a vanadium-rich grossularite that contains 4.52 percent V20 3 , 

the highest va.nadium content reported in garnet to date. 

This garnet is associated with vanadium-bearing tourmaline in the contact zone between quartz veins and 

vanadiferous graphitic hornfels. 

This paper presents preliminary data that establish 

the existence of the vanadimn-rich garnet (an unnamed 

new mineral) and describes its occurrence and geologic 

significance. The garnet is fine grained and can be 

separated iii pure fol'ln only with great difficulty. Spectrographic analyses reported here were made by Nancy 

M:. Conklin, of the U.S. Geological Survey, on a small 

quantity of the purified mineral. Complete chemical 
B-68 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

and mineralogic data will be presented at a later date 

after a quantity sufficient for complete chemical analysis has been separated. 

The Laguna district forms the east end of the southern San Juan Basin mineral belt (Hilpert and Moench, 

1960), one of the world's most productive uranilim 

regions. The largest uranium-vanadium deposits in the 

belt are in sandstones of the Morrison Formation, many 

smaller deposits are in the Todilto Limestone, and a few 

small deposits are in the Entrada Sandstone, all of 

Jurassic age. The sedimentary strata and some of the 

uranium-vanadium deposits of the district are cut by 

diabase sills and dikes, which metamorphosed the rocks 

and ore deposits for distances of a few feet from the 

contacts. The vanadium-rich garnet described here is 

·one of the products of this metamorphism. 

The Sandy mine is in an area where small uraniumvanadium deposits are found in the Todilto Limestone 

and Entrada Sandstone (Hilpert and Moench, 1960, 

p. 457-460). These deposits, the largest of which has 

yielded about 3,000 tons of uranium ore, contain about 

equal amounts of uranium and vanadium. 'Vhere unoxidized, the uranium is largely in coffinite and uraninite, and the vanadium is largely in vanadium clay, 

which is composed of interstratified mica (probably 

roscoelite) and montmorillonite mixed with some 

chlorite (identifications by John C. Hathaway, U.S. 

Geological Survey). Quantitative and semiquantitative spectrographic analyses show that the vanadium 

clay contains 7 or 8 percent vanadium. The clay is 

interstitial to sand grains of the Entrada Sandstone and 

em bays the calcite cement; it occurs also in thin laminae 

in the Todilto Limestone and along boundaries between 

the calcite grains. It is concentrated along small folds 

that formed while the limestone was being deposited. 

The sedimentary strata at the mine are nearly horizontal and have been intruded by many vertical diabase dikes, most less than 5 feet wide, and by sills that 

range from 1 to 75 feet in thickness. Metamorphic effects are conspicuous for several feet above and below 

sills more than about 15 feet thick. The metamorphic 

envelopes are best developed in the calcareous parts of 

the Entrada Sandstone and the Todilto Limestone and 

are marked by the presence of garnet, idocrase, diopside, biotite, plagioclase, epidote, and wollastonite. 

Garnet is the most widespread and abundant metamorphic mineral. Two types of garnet have been distinguished-andradite-grossul a rite and vanadium-rich 

garnet. The andradite-grossularite forms pale-green 

to reddish-brown dodecahedral crystals, occurs as granular aggregates in barren sandstone and limestone, and 

encrusts joints in barren sandstone and in ore. The 

garnet on joints does not contain much vanadium and 

gives X-ray powder patterns similar to standard andradite-grossularite patterns (l\iary E. 1\{rose, written 

communication, 1959). 

Vanadium-rich garnet was discovered in the prospect 

pit in a small uranium-vanadium deposit (fig. 26.1) on 

the contact between the Entrada Sandstone and the 

Todilto Limestone. The deposit is separated by 2 or 3 

feet of limestone from an overlying sill. The sill, 

largerly eroded in the vicinity of the prospect pit., was 

originally about 20 feet thick; garnet is present in a 

zone at least 5 feet thick below the base of the sill. In 

the pit, barren light-tan sandstone is sharply mottled 

and banded with uranium- and vanadium-bearing darkgray to black sandstone. The dark color is caused by 

vanadium clay. 

In thin sections of banded ore, garnet embedded in 

vanadium clay is distinctly darker than that in barren 

sandstone. This relationship was observed within the 

space of a single thin section. Preliminary tests made 

on a small separate ( 10 milligrams) of the darker 

garnet indicated a vanadium content of 21 percent (see 

table, sample G-2a). On the theory that this high 

vanadium content might be caused by impurities, a second and larger sample (25 milligrams) was separated 

and proved to contain 14 percent vanadium (table, 

sample G-2b). Though colored deep greenish brown 

Quantitative and semiquantitative spectrographic analyses of 

vanadium-rich garnet 

[M, major constituent. Nancy M. Conklin, analyst] 

Laboratory Field v AI Fe Mg Ca Ti Mn Ba Cr Cu 

serial No. No. 

--------- ---------- 256540 _______ G-2a I 21 7. I 4. 2 0.15 M 0.3 o. 3 0 0.003 0 289952 _______ G-2b I 14 7. 7. .3 M .15 .3 .007 .03 .007 

1 Quantitative spectrographic determinations; all others are semiquantitative. 

to brownish green, the analyzed material was clear, 

free from inclusions, and contained no visible impurities. It yielded an X-ray powder pattern (9-hour 

exposure) that shows only garnet lines similar in 

spacing and intensity to an andradite standard. 

The high calcium content. of both samples indicates 

that the garnet is a member of the calcium-rich series. 

In this garnet, vanadium, iron, and aluminum probably 

proxy for one another according to the formula 

Ca3 (V,Fe,Al) 2 Si3012· 

As the garnet formed in a uranium-vanadium deposit, one might expect it to contain uranium as well 

as vanadium, but. none was detected. The detection 

limit of uranium by spectrographic analysis is about 

0.05 percent, but as a dilution technique was used, a 

uranium content of somewhat more than 0.1 percent 

might have escaped detection. 

.. 

·~ 

+ 
... ARTICLE 26 B-69 

A 

6050' 

EXPLANATION 

Diabase H 

Todilto Limestone 

D 

Ent:-ada Sandstone 

0 

Outline of uranium·vanadium 

deposit in subsurface 

A' 

6050' 

6000' 

N 

u 

Cll 

Cll 

c( 

0:: 

::I 

...., 

5950' l 

5900' 

Pros.pect pit 

~~~~~::::~~~~~~::~~-~~~~~~~~~__j 5950' 

Uranium·v,nadium deposit 5900' 

~--------~------------------------------------------~~ 0 200 FEET 

CONTOUR INTERVAL 20 FEET 

DATUM ASSUMED 

FIGURE 26.1.-Geologic map and section of part of the Sandy milw, Valencia County, N. Mex. 

The vanadium-rich garnet is embedded in the darkest:. sandstone of the prospect pit and forms less than 

10 percent of the rock. It forms tiny grains ( 0.1 mm 

or .less in diarneter) many of which exhibit sharply 

defined dodecahedral faces. Viewed with a hand .lens, 

the garnet .is clen.r and dark greenish brown to brownish 

green. In thin section it is deep brownish green, is not 

visibly zoned, and is weakly birefringent. It 09curs 

together with brown vanadium cln.y in granular aggregates in the .interstices between detrital grains. Zoned 

garnets with deep-brownish-green cores and colorless 

rims have been found in other parts of the Sandy mine, 

bnt the presence of vanadium in these garnets has not 

yet been verified. 

The diabase dikes and sills have been inferred from 

stJ.'uctural evidence to be younger than the uraniumvanu.dium deposits (llilpert and Moench, 1960, figs. 11, 

17). The presence of vanadium-rich garnet in the contact metamorphic en vel ope further substantiates this 

age relationship, for the garnet must have formed at 

the expense of vanadium-bearing minerals in the ore. 

Vanadium clay is the only vanadium-bearing substance 

identified in the unoxidized ores of t.he district, and 

vanadium-rich garnet probably was a pt·oduct of a 

complex reaction involving vanadium clay, caleite, a.nd 

probably quartz. Other minerals may have acquired 

vanadium during the metamorphic reactions, but they 

have not been investigated. 

REFERENCES 

Bndalov, S. T., 1!151, Vanadium·bearing tourmaline and garnet: 

in Zaph;ki V sesoyuz. l\fineral. Obshchestva ( Mem. soc. 

russe mineral), v. 80, p. 212-213. 

Doelter, C., 1916, Granatgruppe, i·n Handbuch der 1\fineralchemie: Bd. II, 1915-17, p. 878-915. 

Hilpert, L. S., and Moench, R. H., 1960, Uranium deposits of 

the southern part of the San Juan Basin, New Mexico: 

Econ. Geology, v. G5, no. 3, p. 429-464. 
B-70 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

27. THORIUM AND URANIUM IN SOME ALKALIC IGNEOUS ROCKS FROM VIRGINIA AND TEXAS 

By DAVID GOTTFRIED, RoosEVELT MooRE, and ALICE CAEMMERER, 'Vashington, D.C. 

Certain types of aJkalic igneous rocks contain greater 

amounts of thorium and uranium than the ordinary 

calc-alkalic igneous rocks. 'Vithin the broad category 

of alkalic rocks, however, more systematic studies are· 

needed to enable us to correlate the chemical characteristics of contrasting suites with their thorium and 

uranium content. As part of a broad study concerned 

with the geochemistry of thorium and uranium in igneous rocks, analyses for these elements in 51 samples of 

a variety of alkalic igneous rocks from Virginia and 

Texas are presented in this article. 

Thorium was determined by the chemical method of 

Levine and Grimaldi (1958) and uranium by the fluorimetric method of Grimaldi and others (1952). The 

thorium and uranium results given in this report are 

believed to be accurate to about ± 10 percent. 

AUGUSTA COUNTY, VA. 

Three types of alkalic igneous rocks are predominant 

in the dike complex of Augusta County, Va.-nepheline 

( natrolite) syenite, teschenite, and picrite. These rocks 

are being studied by R. vV. ,Johnson, Jr., and Charles 

Milton, of the U.S. Geological Survey, who provided 

the samples, chemical analyses, and information on the 

petrographic characteristics of the samples. An earlier 

deseription of the dike complex was published by Watson and Cline ( 1913). 

TABLE 27.1.-Partial analyses of alkalic igneous rocks from 

Augusta County, Va. 

Si02 CaO Th u Sample Rock type (per- Na20+K20 (ppm) (ppm) Th/U cent) 

---- D-4a _______ Nepheline syenite _____ 57.9 0.02 87 10.4 8. 4 D-48 •. _____ _____ do _________________ 58.0 .03 53 14.0 3. 8 D-42 ...•••. Nepheline (natrolite) 57.8 .Ofi 60 20.0 3.0 syenite .I D-12a. _____ Nepheline syenite. ____ 57.7 .05 40 12.5 3. 2 

g_ ---------- Nepheline (natrolite) 57.7 .05 51 14.8 3. 4 syenite. 

D-2.------- Nepheline syenite _____ 58.3 .09 38 10.6 3. 6 

D-38b •••••• Nepheline (natrolite) 58.1 .02 49 14.1 3. 5 

D-70. ------

syenite. ____ .do _________ -------- 59.0 .01 42 12.1 3. 5 

D-3L ------ Nepheline syenite 1 ___ 57.4 .03 42 12.8 3.3 

D-22c. ----- _____ do ________ --------- 56.9 .02 40 10.3 3. 9 

D-18. ------ _____ do~--------------- 58.7 .07 30 22.0 1.4 D-6-St. 26__ Teschenite •• ____ ------ 51.2 1.4 20 4. 5 4. 4. 

D-14.- ----- ___ .• do _____ --------"--- 59.8 .10 33 8. 3 4.0 D-22b. _____ ...... do ....• ---~-------- 57. 1 . 51 39 11.5 3.4 D-24b. _____ _____ do ....• ---------- __ 55. 1 . 36 18 4. 4 4.1 

D-17-St. 23. _____ do ....• -----------_ 52.2 .fiO 13. 4 4. 4 4.0 

D-1-St. IL ___ •. do _________ -------- 51.8 1.4 21.0 5. 4 3. 9 D·-7 ________ _____ do _____ ------------ 62.9 . 29 13.9 3. 9 3. 6 

D-69 •.•.... _____ do ____________ ----- 51.1 . 93 11.1 3.2 3. 5 

D-8. ------- ____ .do _________________ 48.4 1.1 7. 1 2.8 2. 5 D-14b. _____ Picrite. _______ ------- _ 46.7 1.7 12. 5 3. 4 3. 7 

D-26. ------ n _____ do _____ -----------_ 44.7 2. 2 14.1 3. 0 4. 7 ___________ ___ •• do _____ • ___________ 45.7 2.1 9. 9 2. 6 3. 8 

D-12. ------ _____ do _____ ------- _____ 45.6 3. 4 7. 8 2.0 3. 9 

1 Float material. 

The syenites and teschenit.es a .. re closely related sp~ttially and genetically. The nepheline ( natrolite) syenites consist essentially of potassic felclspar-nephelinenat.rolit.e aggregates, with acmitic pyroxene and little 

hornblende or biotite. The tesehenites contain pla.g:ioclase, diopsidic pyroxene, almndant brown hornblende 

and biotite, ·and analcite. The few picrite instrusives 

consist mainly of olivine, pyroxene and biotite. 

87 

60r------T,-------.-,-----.,-------.-,----~~.~~~--. 

z 

Q 

..J 

..J 

50-

~ 40r 

a: 

w 

0.. 

(/) 

1-

a: 30 r- <( 

0.. 

z 

10-

. . 

. . -

-

-

-

o~----~~-------~~----~~~----~~-------~~----~ z 3 30~-----,,-------.-~------~r------.l-------.-,----~ 

..J 

~ 

a: 

~ 20f-

(/') 

1-

a: 

it 

z 10-

. .. . . 

:·· 

... . . 

I I I I L 

-20 -10 0 10 20 

POSITION t/3 Si02 + K2 0-CoO-FeO-MQO 

-

-

30 

FIGURE 27.1.-Variation diagrams showing distribution of 

thorium and uranium in alkalic igneous rocks from Virginln. 

T bl 1 . . CaO 

a e 27.1 gtves t. 1e s1hca content, the Naz0+J{20 

ratio, and the thorium and uranium content of 24 samples. These data. show a clear trend toward increasing 

-• 

+ 
~-

~--

\ . 

ARTICLE 27 B-71 

thorium and uranium in t-he more siliceous rocks, which 

. 7 s·o d l CaO con tam 5 to 59 percent 1 2 an mve a N· 0 + J( . a.z 2 0 

rat-io of less than 0.1. The syenites average about 48 

ppm of t-horium and 14 ppm of uranium. The most 

maJic rocks, t-he picrites, average 11 ppm of thorium 

and 2.8 ppm of uranium. Figure 27.1 shows a plot of 

the thorium and uranium data on a variation diagram 

of the type proposed by Larsen (1938). Figure 27.3 

shows the relation between the Th/U ratios of the rocks 

and their chemical composition. There appears to be 

no systematic variation of thorium relative to uranium 

bet" ween any of the rock types. 

BIG BEND NATIONAL PARK, TEX. 

The igneous rocks from the Big Bend National Park, 

Tex., area range from alkalic basalt containing about 

44 percent Si02 to riebeckite rhyolite and granite with 

about 7() percent Si02• The suite of rocks constitutes 

one of several alkalic subprovinces along the front of 

t;he Hocky ~1ountains extending from ~1ontana to 

l'exas. Brief discussions of the petrology and geologic 

set;t;ing of these rocks are given by Lonsda.le and ~1axwell ( 1949) and Maxwell and Lonsdale ( 1949). Igneous rocks from the Terlingua-Solitario region (Lonsdale, 1940) are very similar to most of the rocks of the 

Big Bend area. Table 27.2 lists the Si02 content, the 

CaO . l l 1 . d . N· O + l( 0 rat10, anc t:. 1e t wrmm an uran1um conr <12 . 2 

TABLE 27.2.-Partial analyses of alkalic igneous rocks from 

Big Bend National Park, Texas 

Si02 CaO Th u 

Sample H.ock type (per- Na20+K20 (ppm) (ppm) Th/U 

cent) 

----------

Ch689F-2 •. Qtmrtz sani:line 

intrusive. 

porphyry, 76.78 0.03 32 9. 4 3.4 

Ch2:i4 •.••• Hicbeckitc granophyrc, in- 77.47 . OS 45 16.4 2. 7 trusive. 

Ch203 ••••• H.icbcckitc microgmnitc 76.62 . 03 26 9.8 2. 7 

Ch232D ••• porphyry. 

Ric beekite granoph yrc, in- 75.94 .04 26 9. 0 2.9 

trusivc. 

Chi02B •••• Hicbcckit<' granite, intrusive 75. iO . 08 45 42 1.1 Ch746F •••• Ricbcckitc rhyolite __________ 75.09 . 04 41 16.4 2. 5 Ch707A-3 •. Pyroxene m icrograni te, in- 70.00 .14 24 7. 0 3. 4 trusive. 

ChU68F ••.• Hei bccki tc trachyte, extru- 69.14 . 04 40 19. 5 2.1 sive. 

Ch:l40B •••• Aegerine augite trachyte, 66.49 .12 11.3 1.9 5. 9 intrusive. 

Ch61B ••••.. AU!!itc soda trachyte, intru- 65.40 .11 11.6 3. 4 3.4 sivc. 

Chi47C •..• 'l'mchynndcsitc porphyry ___ 64.26 . 23 14.1 (l. 2 2.3 Ch577B •••• ••••• do. ______________________ 63.97 . 57 11.3 a. a 3.4 Ch47H ••••• A nalcite-sycnitc ... __ • __ • ____ 62.76 .10 10.9 3.4 3. 2 Ch726F •••• 'l'mchyandesite .. ----------- 58.60 . 70 9. 5 4. 3 2. 2 Ch258 ••••• Olivine sycnodiorite ...••...• 55.36 . 83 11.0 4. 4 2. 5 Ch727D ••• Basalt porphyry, extrusive ... 55.64 . 96 8. 3 a. a 2. 5 Cht76A •••• Analcite-andesine syenite ... 53.70 . 76 7. 5 2 . .') :t 0 Ch47A .•••• Syenogabbro .• __________ •••• 5:3.40 .83 4. 2 1.6 2.o Ch724 •• __ • Porphyritic olivine basalt, .52. 35 1.4 3.8 1.6 2.4 intrusi vc. Cht79 ••••• Analcite syenogabbro ••. ____ 51.04 1.1 5. 0 1.6 3. 1 Chl48 ••••• Olivine basalt intrusive ..••. 4\J. 90 1. .'i 3. 4 1.2 2.8 ChaS(i ••• __ _____ cto _______________________ 48.40 2. 2 3. 't 1.1 3.1 Chn\JD ••.• Analcite labradorite syenite. 48.51 1.1 4. 7 1.7 2. 8 Ch!i8!J •.••. Olivine basalt porphyry, 47.69 2. 0 2. r; 1.2 2. 2 extrusive. 

Ch8401L .. Basalt, intrusive ..••..••.••. 45.89 2.3 4. 7 1.9 2. 5 Ch243D ••. Nepheline basalt, intrusive .• 43.75 3.1 5. 4 2. 2 2. 5 

Chi. •••••• Porphyritic olivine basalt. .• 46.19 1.8 3. 9 1.9 2.1 

50 I I I I I 

.. z 

0 40 

:::::; -

..J 

~ 

a: 

UJ 

a.. 30 fen 

ta: 

c:t 

a.. 

z 20 

~ 

2 

a: 

0 10 :X: 

. . . - t- . . . . . . . . 0 I I I I I 

50 I I I I I 

z 

0 40 t- - :J 

..J 

~ 

a: 

UJ 

a.. 30 t- -

en 

ta: 

~ 

z. 20f-

~ 

:::l 

z 

c:t 

a: 10 t- :::l 

.. . . . 0

-30 

I • • .. 1 • ~. 1: I •, 

-20 -10 0 10 20 30 

POSITION 1/3 Si02 +K2 0-CaO-FeO-MgO · 

FIGURE 27.2.-Variation diagrams showing the distribution of 

thorium and uranium in alkalic igneous rocks from Big Bend 

National Park, Tex. 

tent for 27 samples. The samples and chemical data 

' were provided by the late Prof. ,T. T. Lonsdale, of the 

University of Texas. The siliceous rocks in the range 

from about ;-,(0 to 77 t s·o l CaO percen 1 2 · utve N O+Ir O a2 ~z 

ratios ranging from about 0.03 to about 0.1, indicating 

they are extremely lime poor. In these rocks the thorium content ranges from about 25 to 45 ppm and the 

uranium content from 9 to 45 ppm. Nearly all the 

rocks contain greater amounts of thorium and uranium 

than corresponding rocks of the calc-alkalic suites 

studied by Larsen and G:ottfried (1960). Figure 27.2 

shows the relation between the thorium and uraniun1 

content of the rocks and their chemical composition on 

a variation diagram. Both thorium and uranium show 
B-72 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

a rather systematic increase from the mafic to the siliceous rocks. The thorium to uranium ratio is nearly 

the same over the range of composition (fig. 27.3). 

Except for two samples, all the Th/U ratios fall between 2 and 3¥2. 

6 I I 

Virg\nia 

I I T 

8.4 

5r -

4-- .. . - . ::J 

. . .. .. ~ 31- - t2- -

II- -

0 I I I I 1 

6 I I I I .. 

5~ Big Bend National Pork, Tex. 

4 -

::J . . ....... . ..t::. 31- . - t- ' .. . 21-

II-

~30 I I I I I 

-20 -10 0 10 20 30 

POSITION 1/3 Si02 + K2 0-Ca0-Fe0-Mg0 

FIGURE 27.3.-Variation diagrams showing the thorium to 

uranium ratios in alkalic igneous rocks from Texas and 

Virginia. 

DISCUSSION 

Although the two alkalic suites of igneous rocks discussed here have significant differences in their mineralogic composition and in some chemical features, they 

CaO 

have similarities with respect to their low 

Na 2 0+ I\:20 

ratio and relatively high thorium and uranium content. The late differentiates of each suite contain 

about 2 to 3 times the amount of thorium and uranium 

found in the highly siliceous rocks of calc-alkalic provinces (Larsen and Gottfried, 1960). 

It is of interest to compare the data given in this 

report with those obtained on the subsilicic-alkalic 

igneous rocks of the Bearpaw ~fountains of ~fontana. 

Chemically the rocks of the Bearpa w ~fountains are 

characterized by a low 8102 content and a high l\: 20 and 

CaO content. The late differentiates of this province 

are syenites which average 14.3 and 4.1 ppm of thorium 

and uranium respectively (Larsen and Gottfried, 1960). 

Their thorium and uranium contents are somewhat 

similar to the amounts found in ]ate differentiates of 

calc-alkalic suites and significantly lower tha.n the 

amounts found in the lime-poor alkalic rocks discussed 

here. 

The data presented here and the previous studies by 

Phair (1952) and Larsen and others. (1955) indicate 

that the distinguishing characteristic of alkalic igneous 

rocks enriched in thoriun1 and uranium is tl~eir extremely low CaO content. Hence these studies provide 

a chemical guide for possibly delineating certain areas 

of alkalic igneous rocks that ·would be significantly 

enriched in thorium and uranimn. 

REFERENCES 

Grimaldi, F. S., May, Irving, and Fletcher, l\1. H., 1952, U.S. 

Geological Survey fluorimetric methods of uranium analysis: U.S. Geol. Survey Circ. 199, 20 p. 

Larsen, E. S., Jr., 1938, Some new variation diagrams for groups 

of igneous rocks: .Jour. Geology, v. 46, p. 505-520. 

Larsen, E. S., Jr., Phair, George, Gottfried, David, Smith, 'V. L., 

1956, Uranium in magmatic differentiation: U.S. Geol. Survey Prof. Paver 300, p. 65-74. 

Larsen, E. S., 3rd, and Gottfried, David, 1960, Uranium and 

thorium in selected suites of igneous rocks: Am. Jour. Sci., 

v. 258-A, p. 151-169. 

Levine, Harry, and Grimaldi, F. S., 1958, Determination of 

thorium in the parts per million range in rocks: Geochim. 

et Cosmochim. Acta, v. 14, p. 93-97. 

Lonsdale, .J. T., liMO, Igneous rocks of the Terlingua-Solitario 

region, Texas: Geol. Soc. America Bull., v. 51, v. 1539-1626. 

Lonsdale, J. T., and Maxwell, R. A., 1949, Petrology of Big Bend 

National Park, Texas [abs.], Geol. Soc. America Bull., v. 

60, no. 12, pt. 2, p. 1906. 

1\iaxwell, R. A., and Lonsdale, .John T., 1!H9, General geology of 

Big Bend National Pari\:, Texas [abs.] : Geol. Soc. America 

Bull., v. 60, no. 12, pt. 2, p. 1908. 

Phair, George, 1952, Radioactive Tertiary porphyries in the 

Central City district, Colorado, and their bearing upon 

pitchblende deposition: U.S. Geol. Survey TEI-247, 53 p., 

issued by U.S. Atomi<.: Energy Comm. Tech. Inf. Service 

Ext., Oak Ridge, Tenn. 

Watson, T. L., and Cline, .J. H., 1913, Petrology of a series of 

igneous dikes in central western Virginia: Geol. Soc. 

America Bull., v. 24, p. 301-334. 

.Jil; 
ARTICLE 28 B-73 

28. SALINE FEATURES OF A SMALL ICE PLATFORM IN TAYLOR VALLEY, ANTARCTICA 

By WARREN IIAMILTON, IRVING C. FRosT, and PHILIP T. HAYEs, Denver, Colo. 

Work supported by the National Science Foundation 

In Taylor Valley, at approximate lat. 77°43' S. and 

long. 162°15' E. in· South Victoria Land, the snout of 

the large Taylor Glacier rests against Bonney Lake 

(fig. 28.1). The lake is thickly frozen during most of 

the year, although in late December and January the 

ice melts in a band a few yards wide around the lake. 

Air temperatures are belo\v freezing except on occasional warm summer days, but ground-surface tempera-

. tures are ·above freezing more frequently. 

-r-- ... ·-

The glacier lies directly against the ice of the lake 

across most of its width ( Ha.milton and Hayes, 1961, fig. 

2). At the north side of the snout, however, a sloping, 

gently rolling platform of ice separates glacier and 

lake (fig. 28.1). The platform is triangular in plan, 

400 by 600 feet, with the obtuse angle at the junction 

of glacier and Jake ice; the platform rises gently toward the Recent. till of the valley side, and even more 

ge11tly up the valley. The platform is probably an ice 

McMurdo Sound 

FIGURE 28.1.-View north across the end of Taylor Glacier, showing location of the saline ice platform. The pictured area is 

4lh miles wide along Taylor Glacier and Bonney Lake. (U.S. Navy photograph.) 
B-74 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

delta, formed by ref~;eezing of melt-\Yater streams from 

th~ small Rhone Glacier and, to a lesser extent, from 

Taylor Glacier. Total relief of the platform is about 

6 feet. This ice platform has a fretted surface due to 

the aceumulation of saline waters on its surface, has 

numerous small saline pools upon it, and the till at its 

edge is thickly encrusted by halite. The iield study 

of the platform ,;.,ras made by Hamilton and Hayes on 

December 15, 1958, before there was appreeiable melting 

of the margin of Bonney Lake, at a time \Yhen the air 

temperature \\"as perhaps 00°F. This artiele \Yas 

largely prepared by J-Iamilton; chemieal analyses are 

by Frost. 

M:elt-\Yater streams from Taylor and Rhone Glaciers 

are entrenched in guJlies a,s deep as 3 feet in the ice 

platform. The surface of the platform is stained 

yellowish brown by minnte granules of iron oxide, in 

striking co11trast to the clean white ice of lake and 

ghcier. The surface is covered throughout by pinnacles of ice one to several inehes hig-h, with sulfatic 

water in the intervening depressions; 1nm1erous small 

pools several feet in diameter and a few inches cleep lie 

upon the ice (fig. 28.2). The pools are moderately 

FIGURE 2g.2.-Sulfl:lte-water pool, with dark precipitate of iron 

oxide and calc-ite, on platform of salt-pitted ice. 

dilute solutions of sodium sulfate and are floored by a 

loose, slimy precipitate of calcite and iro11 oxide. 

Water and sediment from one of these pools were 

colleeted in a single small eontainer and after several 

months were studied in the laboratory. The relative 

composition of solution and precipitate may have 

changed during the intervening months due to the uncontrolled temperatures. The filtered and dried solid 

has the appearance of yellowish orange silt. It consists of about 98 percent calcite in crystals 0.002 to 0.01 

mm long, mostly aggregated in ragged dusters near 0.1 

mm in diameter. Most crystals are anhedral, but some 

are bluntly terminated prisms and a fe'" are rhombohedra and other forms. Gypsum forms rare tablets 

0.05 mm long. Reddish-brown aggregates 0.005 mm in 

diameter of 0.001-mm particles of limonite constitute 

about 2 percent of the sample. The sediment is completely soluble, with effervescence, in cold dilute I-ICl, 

and alnmdant Fe ( OH) 3 is preeipitated from this solution when alkalized \Yith NH4 0H. A dry, untreated 

sample was analyzed by X-ray diffractometer by Theodore Botinelly, \Yho found the only peaks rising above 

background le\Tels to be of calcite. 

The sample solution was filtered from the sediment 

and analyzed by standard quality-of-water methods. 

It was found to contain: 

ANIONS CATIONS 

Equiva- Equiva- Weight lent parts Weight lent parts 

percent per liter percent per liter 

COa-2 ___ -- 0. 054 18 Na+1 ______ 0. 41 178 

HC03-t ___ . 061 10 K+I ___ ____ . 003 0. 8 

CL-1 _____ . 060 17 so4-z _____ . 79 165 Sum ____ 179 - --- Deficiency ________ 31 

Sum ____ 210 --- Sum ____ 210 

The solute is primarily sodium sulfate. The sample 

was too small (12 ml) for determination of ealeium and 

magnesium; the indicated cation deficiency \vould be 

balaneed if 0.060 weight pereent Ca+2 or 0.037 percent 

Mg+2, or an equivalent combination, were present. 

Total salinity is about 1.4 percent by weight. 

The edge of the ice platform is pitted by insolation 

holes, eontaining saline water, around boulders (fig. 

28.:1). Evaporites, mostly halite, as thick as 1 ineh enFIGURE 28.3.-Salt crust at margin of ice platform. An insolation hole about the boulder contains a saline pooL The 

boulder and the lower paTt of the till in the background are 

encrusted with halite and subordinate amounts of other salts. 

.. 

. .... 
1).-

ARTICLE 28 B-75 

crust the boulders and also form a surface crust and 

subsurface cal.iche in the till at the edge of the ice. The 

upper l.im it of salt deposition-the white l.ine near the 

top of figure 28.3---:-rises up valley (left) w.ith a 2° ·slope, 

p:u:n.llel to the surface of the ice platform; this line was 

about l foot; vertically below t-he 1 im it of water-saturn.t'ed till when studied. 

The salt crust disiHtegrates into firm fragments of 

su.nd and granule size when disturbed. Charles B. 

llunt exa.minecl a S<tmple petrographically and found 

about D5 percent of .it to be halite (NaCl) in rough 

0.1-nun cubes clouded by abundant rectangular holes. 

]~[e aJso recognized calcit-e ( CaC03 ) ; a polysynthetically twinned sulfate, probably polylutlite (l(zS04 · 

~fgS04 · 2CaSO 4 · 21CO) ; gypsum ( CaS04 · 7IIzO), 

fm·1ning the largest crystals .in the material; and an 

m't'horhomhic sulfn.t'e, perhaps epsom ite (:~1gS04 · 

7I:CO). Jiydration states of some of the salts may of 

course .lmve changed between times of collection and 

study. Sylvit·e (J(Cl) is possibly present as cubelets 

within lmlit·e cubes. No sodium sulfate was recognized. 

A rn.pid colorimetric test for nitrate by liunt indicated 

a. prob<t.ble content of about 0.1 percent NOa-2

• The 

a.ssernblage is much like salt crusts in Death Valley except that I}O polyhnlite occurs there, according to I:Iunt. 

The same salt; sample was analyzed chemically. 

About 18 percent of it is insoluble, l;trgely windblown· 

si.lt. The poJ:tion soluble after heating repeatedly on 

a. st·earn ba.t'h was analyzed with the following results: 

ANIONS 

ll'eioht 1Jer- cent of total Afolecular .9olnte 1Jercent 

0. 25 

. 52 

55. 2 

3. 1 

StlliL----------

0. 2 

.2 

45 

1.9 

47 

CA'l'IONS 

Weioht per- cent of total Afolecular solute percent 

Na+l ____ _ K-tl _____ _ 

Ca+2 ____ _ 

Mg+2_ ----

39. 7 

. 13 

. 77 

. 36 

Sum __________ _ 

Excess _________ _ 

50 

0. 1 

1. 1 

.9 

52 

5 

The cation excess is probably due to the determined 

values being too high for sodium or too low for 

chlorine. The soluble salt is about 95 molecular percent NaCl, 1.8 percent ~igSO<~, 1.5 percent CaS04, 0.5 

percent each. o:f CaC0:-1' NaHC03, and NazS04, and 0.2 

percent 1(280.,. T'his agrees reasonably well with the 

1n i nera.logic observations. 

.An inconspicuous salt crust is developed· around 

lnuch of Bonney Lake and along 1nelt-water stre~ims 

from Taylor Glacier . and other glaciers. Although 

629660-62-6 

salts must be more concentrated in the small proportion 

of 1 iquid water than in the ice, no water elsewhere about 

the lake or in other melt water was found to have the 

slightest saline taste. 1 

The composition and concentration of the solutions 

of the ice platform must fluctuate during the year to 

mainta.in equilibriwn with the adjacent ice, as air temperatures vary from perhaps -50° to +40°F. The 

solutions must have been near maximmn dilution when 

studied. 

The restriction of the saline solutions t-o the sloping 

ice pla.tfonn is puzzling. The platfonn appears to be 

an ice delta, formed largely by refreezing of melt 

water frmn Rhone Glacier, but nothing comparable to 

·its saline features was seen elsewhere in the region. 

The bright yellow-brown coloration of the ice by ferric 

iron is so conspicuous as seen frmn either the air or the 

ground that similar features could not have been over-. 

looked in the region visited. 

A preliminary concentration of the solution as a saline residumn after freezing is likely, the solutes 

remaining in the last-freezing portion. Evaporation 

must control the subsequent pt;ecipitation of calcite, 

~ron, and salts. Dry winds are nearly constant. 

Rhone Glacier drains an area of granitic rocks, sandstone, diabase, basalt, and surficial 1naterials (fig. 28.1) ; 

the exceptionally large quantities of dissolved matter 

apparently present in its melt water suggest that min-· 

eralized ground, perhaps pyritic, may underlie some 

part of that glacier. vVl!nclblown sa..It from the sea 

presumably_ adds sodium chloride in particular to the 

waters. 

REFERENCES 

Angino, E. E., and Armitage, K. B., 1962, Geochemical study 

of Lakes Bonney and Yanda, Victoria Land, Antarctica: 

Geol. Soc. America Abs. for 1961, Srlec. Rept. 68, p. 129 . 

1 Water as warm as soc was found in a layer at a de(}th of 40 feet 

in Lake Bonney, at an unS[)ecified distance below the ice, hy Angino and 

Armitage (1962) in December 1960. Although their analytical data 

ha ye not yet been IHJblished, they report "highly saline bottom waters'' 

(at a depth of about 100 feet?) having a Cl/S04 ratio of about 70: 1 

and a Mg/Cn ration of 16: 1, and they conchHle that this "indicates a 

prohahle sen-water origin for the dee()er waters." As the· respective 

mtios in sea wate•· nrc only 7:1 and 3:1 (Clarke, 1924, p. l27), the 

basis fot· the conclusion is nnclen•·; further, the sen. has not entet·ed 

'l'nylor Dry Valley during late Qnatet'IHll'Y time (P~w~. 1960; see also 

Ball and Nichols, 1960, p. 1704). :.l'he warm-temperatn•·e layer was 

attt·ibuted hy Angino and Armitage to a high geothermal gnulient or to 

warm springs in the lake bed,; however, no warm springs are known in 

the region, and some other explanation is more likely. 

·Ball and Nichols (1960) found efflorescent salt on unconsolidated ma.-

terials near l\lci\Iut·<lo Sountl a short distance northeast of the mouth of 

Taylor Dry Valley to consist of snhequnl amount~ of NaCI antl Na~S0 • 

They considered the citloride to have come in spray from the nearby sea, 

and the sulfate to have formed from sulfm·lc acid produced by the 

oxidation of pyrite. 
B-76 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

Ball, D. G., and Nichols, R. L., 1960, Saline lakes and drill-hole 

brines, McMurdo Sound, Antarctica: Geol. Soc. America 

Bull., v. 71, v. 1703-1708. 

Clarl{e, F. W., 1924, The data of geochemistry: U.S. Geol. 

Survey Bull. 770, 841 p. 

Hamilton, 'Varre11, and Hayes, P. T., 1961. Structure of lower 

Taylor Glacier, South Victoria Land, Antarctica: Art. 224 

'in U.S. Geol. Survey Prof. Paper 424-C, p. 0206-0209. 

Pewe, ~r. L., 1960, .Multiple glaciation in the ~:IeMurdo Sound 

region, Antarctica-a progress report: ;ronr. Geology, v. 68, 

p. 498--514. 

ANALYTICAL AND PETROGRAPHIC METHODS 

29. INDEX OF REFRACTION MEASUREMENTS OF FUSED HAWAIIAN ROCKS 

By D. B. STEWART, Washington, D.C. 

The relation of the index of refraction of fused rock 

and rock composition has been clearly demonstrated by 

Mathews (1951) and Callaghan and Sun (1956). A 

similar study of 19 Hawaiian rocks was made to evaluate the fusion method for the rapid determination of 

their Si02 content and for possible use to distinguish 

the differentiates of the tholeiitic and alkali basalt magmatic series. 

A uniform fusion procedure was developed from 

controlled experiments using different electrode configurations, arcing times, and arc current on differing 

amounts of sample of the same composition. Fig 29.1 

is representative of these experiments. The arcing 

process and subsequent cooling of the sample cannot be 

1.630 

n 

1.620 

1.615 

1.610 0 30 60 90 120 

TIME, IN SECONDS 

FIGURE 29.1.-Index of refraction (n) of homogeneous glass 

obtained by fusing 15-mg samples of powdered tholeiitic basalt 

for various times in air with a d-e arc current of 5 amp 

(black points) or 10 amp (circles). The starting material 

was glass (n=1.614) containing 10 percent magnesian 

olivine. 

considered controlled processes, so that a variation of 

index of refraction of 0.01 can occur in duplicate samples of hmnogeneous starting material because of 

incomplete fusion or partial recrystallization. Four 

samples were fused frmn eaeh rock studied: The value 

given is the average of at least three determinations, 

and the range of the observations is given as the estimated error. 

About a gram of representative rock was ground to 

-200 mesh, and a split of approximately 15 mg was 

placed in a cavity 0.140 inch deep and 0.140 inch wide, 

·with walls 0.022 inch thick cut in the end of a. 0.184 inch 

pedestal 0.3 inch long at the top of a 0.242 inch diameter 

carbon electrode. The sample ·was fused for 90 seconds 

in a 5-ampere 220-volt d-e arc with a gap of 0.1 inch. 

The water-cooled electrode holders resulted in cooling 

of the glass beads to room temperature .in about 15 

seconds. Index measurements were made to +0.002 on 

the crtished beads, using white light and freshly calibrated immersion oils. 

A suite representative of each of the Hawaiian differentiation series was selected by my colleague D. H. 

Richter, who discussed with me the conduct and signi-

:fic.a.nce of the investigation. The tholeiitic suite was 

from the 1959-60 eruption of l{i]auea which is to be 

described petrographically by IC .T. ~it1ra.ta and Richter 

at a later date. A sample believed identical to one 

described by l{uno, Yamasaki, Iida, and Nagashima 

(1957, p. 182) was studied, as ·was a sample w~th 52.04 

percent Si02 described by Murata and Richter (1961). 

The samples of the alkali basalt magmatic suite were 

collected by G. A. Macdonald as close as possible to the 

localities described by vVashington ( 1923a, 1923b) and 

Cross ( 1904). Possibly some of these samples are not 

chemically identical to the material analyzed, and this 

may contribute to the scatter of the data. 

I~ 
~. 

ARTICLE 29 B-77 

G E1 

\\ 

\\ 

\~ \ . \ 

-2~\u\ 20' 

1.53 \s \ 

1.52 \ \ 

1.51 \ \ 

46 48 50 52 54 56 58 60 62 

WEIGHT PERCENT Si02 

]fiOuln; 2n.~.-Plot of index of refraction ( n) against percent 

SiO~ for fu::;ed Hnwuiinn rock8. Large dots, tholeiitic series; 

boxes, ullmli IJasnlt :-:;eries; vertkal dimension represents 

rnnge of measurements. Line '1.'-1" is the least-squares line 

for the tholeiitic series, K-K' for the alkali basalt series and 

11.-A.' fo1· nil the rocks studied. Dnshed lines indicate standard 

devintions (a) for line il-.A'. 

The results are shown graphically on figure 29.2 and 

are compa.red with similar :investigations by others on 

figure 29.3. Straight lines computed by the leastsquares method (computations by Ralph Eicher, U.S. 

GeologicaJ Survey, using a. digital computer) for each 

rnagrna series and for all the specimens are plotted 

on .tigure 29.2. The regression coefficients a.nd standard 

dev.in.t:ions computed are 

tho.lei it"ic 1nagma. series: 

'\Teight percent Si02=202.15-95.019 n; standard 

deviation= 1.1 

nllmli basalt magma. ser.ies: 

'Veight percent Si02 = 301.69-156.06 n; sta.ndard 

deviation= 2.7 

n.ll specitnens studied: 

"Teight percent Si02=219.27-106.61.n; standard 

deviation =2.4 

The index of refrn.ction 1nea.surement is denoted by n. 

Yoder and Tilley (1957) determined the index of 

refraction of 3 tholeiites and 1 alka.li basalt fron1 Hawaii (analyzed by Tilley and Scoon, p. 63) after 

the samples were fused in sealed platinum capsules 

for 1 to 24 hours. The measurements reported by 

Yoder and Tilley are somewhat .lower than those reported here, possibly because of the different fusion 

method used. However, the least-squares line using 

both their data and all of the present data differs from 

the present data. only by a slightly smaller standard 

deviation. 

There is n. tendency for tholeiitic glasses to have a 

higher index of refraction than glasses with the same 

SiO:! content from the a.lkali basalt series. The over-

.ln.pping ranges of the two series preclude assignment 

of a.n unknown rock to either magmatic series. Moreover, the standard dev.iations are so great that even 

when the Si02 content is known independently, n1any 

IIa.waiian rocks cannot be confidently assigned to either 

series. The general curve derived frmn aU specimens 

studied shows that the fusion method can be used to 

estimate the silica content only to +4.8 percent within 

95 percent confidence limits. I-Iowever, the method 

may be useful for rough approximation of the composition of aphanitic or glassy rocks, such as groundmasses or some pum 1ces. 

The index of refraction of entirely fused tholeiitic 

roeks is 0.009 to 0.019 higher than that of the glass 

orig·inally present, reflecting solution of olivine, pyroxene and ores, oxidation of iron, and volatilization of 

alkalies and H20. 

The most si.liceous tholeiite studied was fresh vitreous rock eontn.ining 54.08 percent Si02 and having an 

original index of refraction of 1.569. 'Vashington 

(1023c, p. 341) found black glassy inelusions of lower 

index ( n near 1.56) in blocks ejected from IGlauea, 

and ~{acdonald ( 1949, p. 65, 76) reported that where 

only 3 to 5 percent interstitial glass remained, its index 

of refraction was less than 1.54.. Chapman ( 1947, p. 

108) reported interstitia] glass with n= 1.555 :in blocks 

ejected during the 1924 phrea,tic explosions at IGlauea, 

a.nd by reference to George ( 1924, p. 365) he estimated 

that this glass contained 53 percent Si02• Chap1nan's 

estimate of Si02 is lower than the present data would 

indica.te. The generally low index of refraetion of 

interstitial glass suggests that differentiation in the 

tholeiitic. series can produce roeks eonsiderably richer 

in Si02 than 54 percent. 

~{a thews ( 1951) proposed that a separate detenninati ve eurve be prepared for· every m~igmatie suite, while 

Callaghan and Sun ( 1956, p. 765) believed a single 

curve would suffice for all igneous rocks. The difference in the curves for tholeiitic and alkali basalt differ-
B-78 GEOLOGICAL SURVEY RESEARCH 19 6 2 

entiates found here lends support to l\1athews' hypothesis, even though the sca.tter and paucity of the data. 

makes it advisa-ble to use the single general curve for 

an unknown I-Ia:wa.iia.n specimen. Furthermore, the 

general I-Ia,waiian curve (fig. 29.3) is m.uch steeper than 

Callaghan a.nd Sun's general curve or the specific curves 

of l\1athews: The Hawaiian tholeiitic series yields 

n 

WEIGHT PERCENT Si02 

li,IGURE 29.3.-Plot of index of refraction (n) against percent 

Si02 for various artificial and natural glasses. 1, Hawaiian 

tholeii-tic series; 2, Hawaiian alkali basalt series; .A-A' general 

determinative curve for Hawaiian artifical glasses; B-B', 

general determinative curve of Callaghan and Sun (1956) 

(sub-parallel dashed lines indicate the range of their observations) ; 3, area coYered by determinative curves for three 

magma suites studied by Mathews ( 1951). 

higher values, and the a.lkali basalt series lower, than 

a.ny points reported by Ca.llaghan and Sun or l\1athews. 

This may be because the I-Iawa.iian rocks are not conbu11inated by siliceous country rock, which is one of 

the unique advantages in the study of I-Iawaiian 

magmatism. 

REFERENCES 

Callaghan, Eugene, and Sun, l\fing-Shan, 1956, Correlation of 

some igneous rocks· of New Mexico IJy the fusion method: 

Am. Geophys. Union Trans., v. 37, p. 761-766. 

Chapman, R. ,V. 1947, Crystallization phenomena in volcanic 

ejecta from Kilauea, Hawaii: Am. Mineralogist, v. 32, p. 

105-110. 

Cross, ·whitman, 1904, An occurrence of trachyte on the island 

of Hawaii: .Jour. Geology, .v. 12, p. 510-523. 

George, ,V. 0., 1924, The relation of the physical properties 

of natural glasses to their chemical composition: .Jour. 

Geology, v. 32, p. 353-372. 

Kuno, H. Yamasaki, K., Iida, C., and Nagashima, K., 1957, 

Differentiation of Hawaiian magmas: .Japanese .Jour. 

Geology and Geography, v. 28, p. 179-218. 

Macdonald, G. A., 1949, Petrography of the island of Hawaii : 

U.S. Geol. Survey Prof. Paper 214-D, p. 51-93. 

Mathews, \V. H., 1951, A useful method for cletermining approximate composition of fine grained igneous rocks: Am. 

Mineralogist, v. 36, v. 92-101. 

Mlirata, K. J., and Richter, D. H., 1961, Magmatic differentiation in the Uwekahuna Laccolith, Kilauea Caldera, Hawaii: .Jour. Petrology, v. 2, p. 424-437. 

Tilley, C. E., and Scoon, .J. H., 1961, Differentiation of Hawaiian 

basalts: Trends of Mauna Loa and Kilauea historic magma: 

Am. Jour. Science, v. 259, p, 60-68. 

\Vashington, H. S., 1923a, Petrology of the Hawaiian Islands, 

pt. 1, Kohala and Mauna Kea: Am. Jour. Sci., 5th ser., 

v. 5, p. 465-502. 

--- 1923b, Petrology of the Hawaiian Islands, pt. II, Hualalai· and Mauna Loa: Am .. Jour. Sci., 5th ser., v. 6, p. 

100-126. 

--1!)23c, Petrology of the Hawaiian Islands, pt. III, 

Kilauea and general petrology of Hawaii: Am . .Jour. Sci., 

5th ser., v. 6, p. 338-367. 

Yoder, H. S., Jr., nnd Tilley, C. E., 1957, Basalt magmas: Carnegie lust. \Vashington Year Book 56, p. 156-161. 

30. DETERMINATION OF SILICA IN TEKTITES AND SIMILAR GLASSES BY VOLATILIZATION 

By MAxWELL K. CARRON and FRANK CUTTITTA, Washington, D.C. 

Work llone in coope1·ation '!1Jith National .Aeronatttica.l a.nd Space A.dntini.lltration 

As part of a systematic investigation of the chemistry 

of tektites, methods are being devised that will provide 

accurate analytical results, allow the study of smaller 

tektite samples, and. conserve valuable museum specimens. This paper presents a volatilization method for 

the determination of silica that will furnish accurate 

analytical results comparable to those obtained by the 

conventional gravimetric (double HCl dehydration) 
II'-

ARTICLE 30 B-79 

or the spectrophotometric (molybdenum-blue) methods, perrnit the detennina.tion of Al, :Mg, Ca, Na, IC, 

Ti, .Fe, P, and ~1n in the same sample taken for the 

silica. determination, and be less time consuming than 

the conventional gra.vimetric procedure. 

An accurately weighed portion of tektite is digested 

with JIF .in a weighed pla.tinum crucible. Silicon :is 

volatilized as SiF4 n.t ste:nn-baJh temperature, and the 

resultant fluoride salts n.re converted to nitrates with 

concentrnted I:INOa. The :nitrates in the residue are 

decornposed with formaldehyde, evnpora.ted to dryness 

on a ste:un bath, and ignited to constant weight at 

7n0°C±15°C. 

The deeomposit.ion of nitrates -with formaldehyde is 

accomplished in two steps, a.s follows: 

4N03 -I-2CII 0~4N0;- -I-2H20+2C02· 

4NO;-• + 3CH 0~2N 2 + 3C0z + 02 + 3Hz0 

The residue contains the oxides of Al, Fe, Cn., ~1g, Nn., 

IC, Ti, ~fn, P, a.nd the trac('. constituents. These oxides 

u.re brought into solution by digestion with a mixture 

o:f I-IF· £[Cl0., followed by heating to fumes of 

liCl04 • Except for the determination of ferrous iron, 

one sample c:tll be used for the deterrnination of all the 

mttjor constituents of tektites. 

The method n.ppears to be especially suited to the 

detennina.tion o:f Si02 in tektites because of their low 

alkali. eontent n.nd almost complete absence of vohttile 

constituent·s such as C02 and J:CO. A correction must 

be mn.de for the oxidation of FeO ·to Fe20:~ after the 

finn.l .ignition to constant weight. 

P1··ooed'wre-T'o 0.2000 g of sample in a weighed 

platinum crucible, add 2 1nl of water and 4-5 ml 4~ percent lfF. Cover with n. plat.innm cover n.nd digest on a 

steam bath :for n.t least 2 hours. Uncover, evaporate the 

solution to about 2 ml, and add 5 ml cone JINOa. 

Evaporate the solution to dryness. Repeat the evaporation tw.iee with 5-ml adclitions of cone lTNOa. Add 

two !5-ml portions o:l: formaldehyde, and evaporate to 

dryness each time to destroy nitrtttes. Allow the second 

ev:tporation to proceed overnight. lfeat the partially 

covered crucible gent~lj in nn air bath, gradua.lly raising 

the temperature to full heat of the burner. Continue 

heating for another lfi miHutes. Transfer the crucible 

to a regulated mufHe furnace. fleat at 750° C± 15° C 

for 3 hours with the cover slightly aside. to allow oxidation of :iron to the ferric state. 'Veigh and repeat the 

heating for additional lj2-hour periods until constant 

weight .is obtained. The loss in weight after ignition 

to constant weight, corrected for the oxidation of the 

FeO originally present in the tektite to Fe20a, represents the silica content of the sample. 

The temperature of ignition of the residues is cr.itical. 

Constant ·weights obtained at 750° C ga.ve silica values 

comparable to those obtained by conventional gravimetric or spectrophotometric methods. Igniting at 

700° C for 4 hours ga.ve lower silica values, ranging 

from 1 to 2 percent absolute below acceptable values. 

At 800° C, results were high by nearly 0.5 percent 

absolute. 

The possibility of loss by vol:-..tilization of the alkalies 

at the temperature (750° C) of ignition to constant 

weight was investigated. The n.lka1i eontent (Na20 

and I\:20) of the ignited residues was determined by 

flame photometry. The results show no significant difference from those obtained for the original untreated 

tektite samples. The described procedure was devised 

primarily for use as an independent and accura.te 

method for the determintion of silica in tektites a,nd 

other similar glasses. 

The table below presents a comparison of silica determinations by the volatilization-formaldehyde method 

with those by the conventional gravimetric or spectrophotometric methods. All results are well within 1 

percent (relative) of each other. Our data also indicate that this procedure provides a better reproducibility 

of results than the conventional gravimetric or spectrophotometric methods. 

Comparison of determinations of Si02 in tektites by various methods 

Spectra- Tektite 1 Gravimetric 2 photo- Volatilization • metric3 

Bediasite B-6-- __________ ------------- 76. 4 76. 26 

Bediasite B-50 ___________ ------------- 78. 4 78. 15 

Bediasite B-85 ___________ ------------- 75. 7 75. 77 

Bediasite B-86 ___________ ------------- 75. 4 75. 45 

Synthetic bediasite 5 ST-L_ 76.47,76.27_ ------ 76.41,76.35 

Synthetic bediasite 5 ST-2 __ 76. 19, 7f). 90_ ------ 76. 13 

Synthetic australite 6 ST-3 __ 75. 90, 75. 44_ 75. 6 75. 30,75. 59 

Synthetic australite 6 ST-4 __ 75. 89. 75. 60_ 75. 8 75. 85,75. 80 

Synthetic aust.ra1ite6 STG-2_ 7 4. 9 5- - - - - - - 75. 2 74. 88 

1 Naturnl-bediasite samples are from Lee County, 'l'cx. :.! Double dehydration with HCI plus recovery of SI02 from the R20:J· '

3 Avernge of 6 determinations by the molybdenum-blue method. 4 Volatilization-formaldehyde procedure described in this report. 5 Prepared according to an average bediasite composition by Corning Gla!-\S Co. 0 Prepared by Dr. Dean Chapman, Ame:s Research Center, Moffett 

Field, Calif. 
B-80 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

31. USE OF La20a AS A HEAVY ABSORBER IN THE X-RAY FLUORESCENCE ANALYSIS OF SILICATE ROCKS 

By HARRY J. RosE, JR., IsiDORE ADLER, and FRANCIS J. FLANAGAN, Washington, D.C. 

The major problem in the development of an X-ray 

fluorescence method of analysis applicable to a wide 

variety of silicate rock types has been the matrix of the 

sample for analysis. For a number of reasons the 

problem is particularly great for the light elements. 

The X-ray fluorescence yield is lmv and the absorption 

by the detector is high. Further, these intensities can 

be altered considerably because of the large absorption 

coefficients for the light elements. Problems of absorption can be n1inimized in various ways such as by dilution of the sample, by the use of internal standardization, and by the use of a he~nry absorber as is described 

here. 

To minimize interelement effects by the dilution 

method, a large diluent-to-sample ratio is required ·with 

a resultant loss in intensity that would interfere with 

the analysis of the light elements. Andermann (1961) 

. and Claisse ( 1956) have discussed the heterogeneity of 

powdered samples even after long grinding periods and 

have indicated that one cannot reduce the particle size 

sufficiently to eliminate m.ineralogic differences from. 

sample to sample. For the same reasons, the mechanical addition of a heavy absorber to the dilution mixture 

fails to improve either linearity or scatter, serving only 

to decrease counting rates. 

The internal standardization method has been treated 

comprehensively by Adler and Axelrod ( 195-5). The 

method requires the selection of an element as an 

internal standard that will be absorbed in the same 

way as the element to be analyzed. This technique 

works we.ll when one element, or even several, is involved, but the method would prove cumbersome for the 

analysis of a large number of elements. 

Of the several methods of sample preparation, that 

of smoothing the surface of a finely powdered sample 

(Chodos and Engel, 1961) has the advantage of speed 

and simplicity but requires the use of sets of standards 

whose composition approximates that of the rocks to be 

analyzed. Although both their unknowns and standards were amphibolites, these authors did not report 

Si02 and AlzOa, the main constituents of silicate rocks, 

because of the poor precision of these detern1inations. 

Two considerations are important to the success of this 

method: The standards must be mineralogically similar 

to the samples to be analyzed, and all preparations must 

be of uniform particle size. 

Claisse (1956) made borax fusions to eliminate 

mineralogic and particle-size effects and analyzed 

molded, fused buttons. To avoid problems of absorption he used a large flux-to-sample ratio to analyze 

elements of intermediate atomic number where high 

intensities are available, but large dilutions cannot be 

tolerated for the light elements because of low 

intensities. 

Andermann ( 1961) fused cement nnY mixes with an 

equal weight of lithium tetraborate and demonstrated 

the improvement of analyses of fused samples over 

those using powdered, unfused materials. The method 

is described as eliminating standardization by type of 

material but requires extensive calculations to correct 

for differences in composition~ 

Claisse ( 1956) mentioned the addition of a heavy 

element to the fusion mixture to produce a more absorbing glass. The addition causes some loss in intensity 

for the lighter elements but should minimize differences 

due to absorption. 

Since samples to be analyzed might contain varying 

amounts of strongly absorbing elements, the effect of 

these elements might be minimized by introducing into 

the sample melt a strong absorber, an element of high 

atomic number, i1Yan amount such that the variation in 

concentration of absorbing elements in the unknown 

sample will not materially affect the overall absorption 

of .the pellet for the elements being determined. Lanthanum is a strong absorber, is readily available at a 

moderate price in the form of the oxide, and offers the 

least interference to the elements to be analyzed. 

Several methods of preparation have been tried in 

this study. A set of six analyzed materials covering 

a range of silica usually found in rock analysis was 

prepared by each of three methods:. (1) One part of 

sample ground to 325 n1esh is mechanically mixed with 

four parts of boric acid; (2) 0.250 g of sample is fused 

with 1.250 g of Li2B40;; and (3) 0.250 g of sample is 

fused with 0.250 g of La203 and 1.000 g of Li:!B40 7 • 

Fusions are made in graphite crucibles. After a preliminary heating at 750° C to remove CO:! and l-I2Q, 

the samples are fused at 1,000° C for 8 to 10 minutes. 

The cooled bead is 'Yeighed to determine loss on ignition 

of the sample and sufficient boric acid is added to bring 

the weight to 1.600 g. The bead and boric acid are 

ground together in a mixer-grinder to pass a 325-mesh 

screen. The boric acid serves as a binder in pressing a 

pellet and obviates differences in ignition losses from 

sample to sample. The samples are double pelleted 

with a boric acid backing as described by Rose and 

Flanagan (Art. 32). 

The counting-rate data for Si02, CaO and Fe20 3 for 

each of the three preparations and duplicate determinations are plotted against concentration (fig. 31.1). 

...... 
~ ,A. y T L.J r .A-' r y :~ .,. (L ·f>' y 

Joor 

1 

, =~ I v l sooo 

600 I 

20J / J 50J I J :::: 

"" a lOOd 

~ z ~ 0 "" u a 0.. t)l z 

6 ~ lll. I 5 § 0 

u 

I I I I I I I 

0 

I J ,_ 

z 

~ "" 0.. ~3000 wo ~ . 6 u 

0 

~ ~2000r' u ~ ~ ~ 0 

t"4 

~ 

200 woo '"' 

'~I v 

0 ~ 3000 

2000 

100 1000 

OL-~-L--L-~~--L--L~L-~~--L-~ 

20 30 40 50 60 70 80 10 5 10 15 20 25 30 

PERCENT Si02 PERCENT Fe ~ PERCENT CaO 

FIGURE 8l.l.-Si02, F~Oa, and CaO calibration curves for samples prepared by mechanical mixing (top), with Li2B,01 (middle), and fusion with La20a to 

and LhB.07 (bottom). ck 

.......... 
B-82 GEOLOGICAL SURVEY RESEARCH ) 9 6 2 

For samples mechanically mixed, the CaO data show 

excellent linearity over the range, the results for FezOa 

are scattered widely, and the data for SiOz are curvilinear. Although a linear curve may be drawn for 

Si02, the scatter of points for samples simply fused 

with Li 2B4 0 7 indicates that the calibnttion curves are 

of little value. The problem encountered in both of 

these preparations is the large absorption differences 

among the samples chosen. 

The decrease in scatter and the improvement in the 

calibration lines when a heavy absorber, La2 0 3, is present can be seen in the curves. Minor problems remain 

of determining the optimum ra.t.io of La20 3 to Li 2B4 0 7 

in the sample. The method, however, has been used to 

analyze successfully a variety of materials with results 

agreemg within 1 percent of the che1nical determination. 

REFERENCES 

Adler, I. and Axelrod, J. M., 1955, Internal standards in fluorescent X-ray spectroscopy: Spectrochim. Acta, v. 7, p. 

91-99. 

Andermaun, George, 1961, Improvements in the X-ray emission 

analysis of cement raw mix: Anal. Chemistry, v. 33, p. 1689~ 

1695. 

Chodos, A. A., and Engel, C. G., 1961, Fluorescent X-ray spectrographic analysis of amphiuolite rocks: Am. Mineralogist, 

v. 46, p. 120-133. 

Claisse, F., 1956, Accurate X-ray fluorescence analyses without 

internal standard: Department of Mines, Province of Quebec, Canada, P.R. 327,16 p. 

32. X-RAY FLUORESCENCE DETERMINATION OF THALLIUM IN MANGANESE ORES 

By HARRY J. RosE, JR. and FRANcr~ J. FLANAGAN, ·vvashington, D.C. 

The X-ray spectrographic technique has been demonstrated as a useful tool for the determination of elenlents of geochemical interest (Adler and Axelrod, 

1955, Axelrod and Adler, 1957). The determination 

of thallium is required occasionally, but the chemical 

procedure is frequently con1plicated by interference 

from geochemically rela.ted elements. A rapid X-ray 

spectrographic method for determining thallium in 

manganese ores has been developed that requires 100 

mg (milligrams) of sample. vVhile the method described will determine thallium down to 100 ppm (parts 

per 1nillion), the present study indicates that as little 

as 10 ppm can be detected. As in most X-ray fluorescent n1ethods, the prepared samples and standards are 

not destroyed during the analysis and may be used for 

further study. 

A set of synthetic standards is prepared by dilution 

of pure thallous nitrate with a 1nixture containing 90 

percent manganese dioxide and 10 percent ferric oxide. 

By successive dilution of the thallous nitrate the composition of the standa.rd approximates the major constituents of the sample to be analyzed. Each dilution 

mixture is ground in an agate mortar to pass a 325-mesh 

screen. The standards in this study cover a range from 

0.01 to 1.00 percent thallium. 

The sample is ground to pass a 325-mesh screen. One 

hundred milligrams of the sample or standard is mixed 

with 900 mg of H3BOa in an agate mortar until homogeneous. The mixture is then pressed into a pellet 1 

inch in diameter. For additional strength the pellet is 

prepared as a double layer by lightly pressing approximately 1 gram of BO:~ in the mold and then adding 

the sample-boric acid mixture onto this pellet in the 

mold before final pressure is applied. Sample numbers 

and other data may be written in ink on the smooth 

face of the boric acid backing, and the pellets thus 

formed may be stored indefinitely in pill boxes for 

future use. Dilution a.t this level tends to minimize 

interelement effects. 

The instnunent consists of a two-channel fluorescent 

air-path X-ray spectrometer (Adler and Axelrod, 1953) 

with lithium fluoride analyzing crystals. l(ryptonhalogen filled Geiger counters are used ·with simultaneous counting by scalers operating in parallel. A 

tungsten target X-ray tube is operated at 50 kilovolts 

and 20 milliamperes. Two measurements are made: the 

time required to accumulate 10,000 counts for the Tl 

La line, a,nd the nmnber of counts recorded for the 

background position dbring this interval. 

.. t. 
l, 

) 

J 

ARTICLE 33 B-83 

The .intensity of the background line at 33.30° 20 is 

subtracted from. the intensity of the Tl La ljne at 

34.87° 20. A strnight-line calibra,tion curve is obtained 

over the range of 0.01 to 1.00 percent. thallium. The 

table below gives the data obtained on five samples 

analyzed by this method and the chemical values obtained by Cuttittn, (1961). 

Scml7>le 

! _____________________ _ 

2 _____________________ _ 

3 _____________________ _ 4 _____________________ _ 5 _____________________ _ 

X-ray 

0. 23 

. 34 

. 07 

. 02 

. 28 

Thalli1tm (percent) 

0. 24 

. 36 

. 073 

. 017 

. 27 

Chemical 

0. 20 

. 37 

. 067 

. 017 

. 27 

0. 24 

. 38 

. 070 

. 017 

. 30 

The X-ray results were obtained by com1ting each 

standard and SHJnple twice :in a randmn order. The 

standard deviation of a single observation calculated 

from the duplicate net-counting rates for samples and 

standa.rds is 0.31 counts per second, equivalent to 0.005 

percent Tl. The speed of the method may be demonstrated by the time necessary to prepare the pellets and 

count the set of fi.ve samples. Results on these samples 

were obtained within 4 hours, including the preparation 

of the standn.rds. 

For samples having a concentration of thalliun1 an 

order of ma.gnitude lower than the values given above, 

it is possible to extend the lower limit of detection by 

reducing the amount of boric acid to be added to the 

samples and standards. However, problems of absorption become more critical as the proportion of diluent 

is reduced. vVhile the determination of thallium 

described herein was applied to manganese ores, the 

method can easily be adapted to other materials or 

elements of geochemical interest by preparing a set 

of standards whose matrix is similar to that of the 

material to be analyzed . 

REFERENCES 

Adler, Isidore, and Axelrod, J. l\f., 1953, A multi-wavelength 

fluorescence svectrometer: Opt. Soc. America Jour., v. 43, 

p. 769-772. 

--1955, Determination of thorium by fluorescent X-ray 

S])ectrometry: Anal. Chemistry, v. 27, p. 1002-1003. 

Axelrod, .J. :M., and Adler, Isidore, 1957, X-ray spectrographic 

determination of ce:;ium and rubidium: Anal. Chemistry, v. 

28, p. 1280-1281. 

Cuttitta, !!"rank, 1961, Dithizone mixed-color method for determining small amotmts of "thallium in manganese ores: 

Art. 290 in U.S. Geol. Survey Prof. Paver 424-C, p. C384-

C385. 

OCEANOGRAPHY 

33. ELECTRODE DETERMINATION OF THE CARBON DIOXIDE CONTENT OF SEA WATER AND 

DEEP-SEA SEDIMENT 

,>- By G. V\T. l\1oOim, C. E. RoBERSON, and H. D. NYGREN, l\1enlo Park, Calif., and U.S. Coast and Geodetic 

~· 

Survey, Washington, D.C. 

Wo1·k done in COOlJeration wUh the U.S. Coast and Geodetic Su.rVf?Y 

The Pco2 (partial pressure of carbon dioxide) was 

determined :in samples of water and sediment in the 

North Paci.fic using a Pco2 electrode originally designed 

for medical studies of human blood. This work was 

done aboard the U.S. Coast and Geodetic Survey 'ship 

Pionee'r :in September and October 1961 as part of a 

general investigation of the geochemistry of deep-sea 

sedirnent. The determ.inations compare favorably with 

theoreticnJ caJculations and provide new data on the 

distribution. of carbon dioxide in the North Pacific. 

The Severinghaus P co2 electrode incorporates the 

glass-electrode principle (Severinghaus and Bradley, 

1958). The instrument consists of a glass-calomel 

electrode pair mounted in a bicarbonate solution n.nd 

separated from the sample to be measured by a thin 

'refton membrane (fig. 33.1). The nl.embrane permits 

passage of carbon dioxide molecules from the smnple 

into the bicarbonate solution while excluding ions that 

might alter the pl:I of the solution. Carbon dioxide 

from the sample pass~s through the Teflon 1nembrane 
B-84 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

NaHC03 +KCI Glass electrode 

FIGURE 33.1.-Diagram of the Severinghaus Pco2 electrode. 

and equilibrates with a very thin .layer of the bicarbonate solution carried by a cellophane film adjacent to the 

glass electrode. The electrode pair then records the 

pii of the bicarbonate solution which is a rneasure of 

the P co2 of the sample. 

The carbon dioxide' content of the samples from the 

North Pacific was determined as soon as possible after 

the samples were collected so as to minimize carbon 

dioxide loss. The samples of water and sediment were 

< 

~ 

en 

< 

~ 

< 

0 500 

injected by means of a hypodermic syringe through a 

slender tube into the sample chamber of the electrode, 

which ·was sealed except for an overflow tube. The 

electrode was immersed in a constant-temperature bath, 

and the readings were made at a fixed elevated temperature of 40°C, which increased the sensitivity of the 

instrument. Readings are corrected to 25°C or to 

natural temperature in the ocean using the values of 

Henry's constant given by Harned and Davis ( 1943, 

p. 2033). Approximately 10 minutes was required to 

reach equilibrium with the water samples and 2 minutes 

with the sediment samples, which were richer :in carbon 

dioxide. The lower limit of detection was 0.0006 atm 

(atmosphere) for analyses quoted at 25°C and 0.0003 

atm at 1 °C. The instrument could be used continuously for analyzing water samples, but it had to be 

disassembled and cleaned after each secbment analysis. 

The sediment samples 'yere taken in piston and 

Phleger coring devices, 'and the water samples were 

collected in Nansen bottles. Frank C. Rainw·ater, lJ.S. 

Geological Survey, and Theodore Ryan, U.S. Coast and 

Geodetic Survey, participated in the shipboard investigation. 

The Pco2 determinations on sea-water samples are 

shown on a profile along the 160th meridian from 

Alaska to Hawaii (fig. 33.2). Additional data are 

given in figure 33.3 for a typical station about 350 kiloJneters northwest of :Honolulu. Pressure is not considered in the illustrations, to permit the surface and 

deep water to be compared. The actual Pco2 at depth 

is higher than shown owing to the effect of pressure on 

flenry's constant. 

The carbon dioxide content is low in the top few 

hundred meters of the sea where it approaches equilib-

--

< ::: 

30"N ~DEPTH (meters) 

0 

1000 

2000 

3000 

4000 

5000 

6000 

7000 

1000 KILOMETERS 

FrounE 33.2.-Pc02 at natural temperature in the ocean determined at oceanographic stations along the 160th meridian. The 

black· zone indicates values greater than 0.0008 atm; the dark gray, values between 0.0004 and 0.0008 atm; and the 

light gray, values less than 0.0004 atm. Values for some neat-surface samples were calculated from the alkalinity and 

the pH. 

j 

• 

\. 

_, 

, 
' 

.... 

L 

J 

\., 

ARTICLE 33 B-85 

0 

1000 rr 

<n 

0:: 

w 2000 1-

\ 

\ 

I 

v 

I 

-

w 

~ 

J: 

1-

Q. 3000 w 

c 

4000 1-l-~1----1 

0 15 36 0 6 0 0.001 7 8 9 

TEMPERATURE OXYGEN Pco2 pH 

(degrees C) (ml per liter) (atmospheres) 

l~'IGUHE 33.3.-Pco:! nt unturnl temperature and other properties 

o.f sen wnt:er from lnt 23°30' N., long 159°58' W. 

r:ium with the low content of the atmosphere. The 

carbon dioxide content reaches a maximum value at a 

depth of about a. thousand meters, which is approxin1ately the depth of minimum oxygen pressure. At 

this depth orga.Iric material sinking from the surface 

decays rapidly, but photosynthetic utilization of carbon 

dioxide cn.nnot occur because light :is almost absent. 

The interJnedin.te layers, which constitute the greatest 

part of the water of the North Pacific, ha. ve a carbon 

dioxide tension a.verag.ing 0.0006 atm, or about twice 

that of water in equilibrium with the atmosphere. This 

P 002 reflects 11 balance between the rate of overturn of 

this pr.incipa.] part o:f the water mass a,nd the production 

of ca.rbon dioxide by decay of sinking debris and by 

the respiration of the rare indigenous animals in this 

·'zone. 

A tongue of water thn.t has a carbon dioxide concentration only a. little 'gl'eater than that of the surface 

wa.ter occupies the :floor of a broad trough north of 

IIn.wn.ii (fig. 33.2) and north of the station illustrated 

:in :figure 33.3. The tongue is proba.bly made up of 

wn,ter that has most recently been added to the circulation system. Theoretical studies of oceanic circulation 

and obsel'vat.ions of temperature, salinity, and dissolved 

oxygen content suggest that this cold dense water 

descended near Antarctica and moved northward along 

the floor of the ocean to its present position ( Stommel 

and Arons, 1960). 

In table 33.1 the 1neasured values of Pc02 a.t the station 

illustrated in figure 33.3 are compared with theoretical 

values derived from measurements of the pH and titru.tion alkalinity. This n1ethod for calculating P co2 

is based on the two following dissociation reactions 

( 1 and 2) and a stoichiom~tric relation ( 3) : 

C02+H20=H+1+HC03- 1 (1) 

HC03- 1=H+1+C03- 2 (2) 

Muco3- 1+2Mco3-2=A (3) 

The equilibrium expressions for (1) and (2) are based 

on activity values, where the activity (a) is defined as 

the product of the molality (1n) and the activity coefficient ( y) of an individual species: In (3) it is necessary to use molar concentrations (JJ/), because the 

alkalinity (A) is expressed in equivalents per liter of 

acid used to titrate to pH 4.5. (The principal titratable 

constituents are assmned to be fiC03- 1 and C03- 2 • At 

values below pH 8.0 the contribution to the alkalinity 

by borate is less than 2 percent and has been ignored.) 

TABLE 33.1.-Comparison between measured and calculated values 

ofPco2 at 25° Cinsea water from lat 23°30' N., long 159°58' W. 

.Measured Alkalinity Calculated 

Depth (meters) Pco2 pH (equivalents Pco2 

(atmospheres) per liter) (atmospheres) 

1 ________________ <O. 0006 8. 20 0. 00247 0. 0003 191 ______________ <. 0006 8. 12 . 00256 . 0004 389 ______________ <· 0006 7. 95 . 00243 . 0006 588 ______________ . 0011 7. 79 . 00254 . 0009 716 ______________ . 0013 7. 62 . 00251 . 0014 895 ______________ . 0014 7. 62 . 00256 . 0014 1075 _____________ . 0016 7. 61 . 00259 . 0014 1343 _____________ . 0014 7. 58 . 00256 . 0015 1612 _____________ . 0011 7. 59 . 00262 . 0015 2726 _____________ . 0010 7. 65 . 00259 . 0013 3693 _____________ . 0011 7. 63 . 00259 . 0013 4380 _____________ . 0011 7. 63 . 00262 . 0013 

The equilibrimn constants K 1 and K 2 for (1) and (2) 

respectively at 25cC were calculated as 10-7

· 80 and 

10-10· 

33 frmn free energy values given by Rossini and 

others (1952). The activity of water in sea water was 

taken as 0.98 (Harvey, 1955, p. 169), and 'YHco3-I and 

'Yco3-2 were taken . as 0.36 and 0.019 respectively 

(Sverdrup and others, 1942, p. 205). · 

In the equilibrium expressions (1) and (2), the concentrations expressed in n1olalities were calculated to 

n1olarities for use in (3). For sea water with an average 

salinity of 34.5 parts per thousand, the relation m= 

1.010M applies. It is co'nvenient to write (3) as 

mHco3-t +2mco3-2= 1.010A. 

From (2), using the stipulated conditions, 

10-9 ·

05mHco3

-l 

And fron1 (1), assuming aco2=Pco2 , 

aH+i mHcoa-1 

l0-7.37 

(4) 

(5) 

(6) 
B-86 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

Finally, by combining (4), (5), and (6), replacing aH+l 

by pH, and collecting tern1s, the following relation 

between the Pco2 in atmospheres, the alkalinity m 

equivalents per liter, and the pH is derived: 

10-2pHA 

Pco2=10- <PH+7.a7> +7.

59 x 10-11 (7) 

Comparison in table 33.1 between the calculated values of P co2 and those measured aboard the ship suggests 

that the values for the activity coefficients used in the 

calculations are reasonably accurate. Perhaps the 

electrode could be used to refine these values, however, 

in carefully controlled laboratory experiments. 

The p C02 of the sediment in a layer 2 to a centimeters 

below the sediment-water interface is given in table 

33.2 for 13 localities in the North Pacifi~. The values 

are remarkably uniform, averaging about 0.007 atm, 

and show no systematic variation with respect to either 

latitude or depth. The average value is about 20 times 

that of ·water in equilibrium with the nt1nosphere, and 

the carbon dioxide probably resulted from decay of 

organic material within the sediment. The relatively 

uniform carbon dioxide content is less surprising when 

considered together with the uniformity of the other 

aspects of the physical environment: The temperature 

of the bottom probably does not differ by more than 

1 oc; the pH ranges only 0.7 pl-I units; and the Eh 

ranges 0.20 volts. Romankevich ( 1961) states that the 

organic-carbon content of northwest Pacific sediment 

ranges between 0.2 and 0.8 percent. Variations within 

this range and differences in the rate of diffusion into 

the overlying sea water probably account for the observed differences in the P co2 of the sediment. 

TABLE 33.2.-Pc02 at 25° C and other properties of deep-sea sediment in a layer 2 to 3 centimeters below the sediment-water interface. 

[Colors of the wet sediment follow the convention of Goddard and others (1948)] 

Location 

LatN Long W 

51° 41'--------

500 24' -------- 450 50'--------

41° 31'--------

390 20'--------

36° 50'--------

32" 42' -------- 300 06' -------- 250 55'--------

240 42' -------- 230 30' -------- 230 29' -------- 230 22' --------

161 ° 07,-- - - - - 176° 30' _____ _ 176° 47' _____ _ 160° 31' _____ _ 

160° 24' ------ 177° 30' _____ _ 

160° 12' _____ _ 177° 30' _____ _ 

177° 34' _____ _ 166° 24' _____ _ 

159° 58'------

1720 23' ------ 177° 54'------

Depth 

(meters) 

4, 670 

7, 260 

5, 450 

5, 490 

5, 400 

5, 250 

5, 820 

5, 290 

5,070 

4, 690 

4, 820 

4, 630 

5, 120 

REFERENCES 

Sediment Color 

Silty clay ___________ Dusky yellowish brown ___________ _ Sandy clay _________ Dark yellowish brown _____________ _ Clay_______________ Moderate brown _________________ _ _ ____ do _____________ Moderate yellowish brown _________ _ _____ do __________________ do __________________________ _ 

_____ do_____________ Dark yellowish brown _____________ _ _ ____ do __________ ·___ Moderate brown _________________ _ _ ____ do __________________ do __________________________ _ _ ____ do __________________ do __________________________ _ _ ____ do __________________ do __________________________ _ _____ do __________________ do __________________________ _ 

Silty.clay ____ _ _ _ _ _ _ _ Dark yellowish brown _____________ _ Clay_______________ Moderate brown _________________ _ 

Pco2 

(atmospheres) 

0. 0058 

. 0077 

. 0055 

. 0090 

. 0058 

. 0056 

. 0075 

. 0052 

. 0059 

. 0072 

. 0056 

. 0091 

. 0063 

pH 

Eh 

(volts) 

7. 2 +O. 28 

7. 0 +. 42 

7. 5 +. 35 

7. 7 +. 34 

7. 4 +. 38 

7. 5 +. 43 

7. 2 +. 38 

7. 3 

7. 3 

7. 3 

7. 3 

+. 48 

+. 42 

+. 43 

Goddard, E. N., chm., and others, 1948, Rock-color chart : 

\Vashington, Natl. Research Council, 11 p. 

Rossini, F. D., \Vagman, D. D., Evans, \V. H., Levine, S., and 

Jaffe, I., 1952, Selected values of chemical thermodynamic 

properties: Natl. Bur. Standards Circ. · 500, 1268 p. 

Severinghaus, J'. \V., and Bradley, A. F., 1958, Electrodes for 

blood p02 and pC02 determination: Jour. Applied Physiology, v. 13, p. 515-520. 

Harned, H. S., and Davis, R., Jr., 1943, 'l'he ionization constant 

of carbonic acid in water and the solubility of carbon dioxide in water and aqueous salt solutions from 0 to 50°C: 

Am. Chern. Soc .. Jour., v. ·65, p. 2030-2037. 

Harvey, H. W., 1955, The chemistry and fertility of sea waters: 

Cambridge Univ. Press, 224 p. 

Romankevich, E. A., 1961, Organic substance in the surface layer 

of bottom sediments in the western Pacific Ocean: Pacific 

Sci. Cong., lOth, Honolulu 1961, Abs., p. 384-385. 

Stommel, H., and Arons, A. B., 1960, An idealized model of the 

circulation pattern and amplitude in oceanic basins, pt. 2 

of On the abyssal circulation of the world ocean : Deepsea Reseai;ch, ~- 6, p."217-233. 

Sverdrup, H. U., Johnson, l\1. "r., and Fleming, R. H., 1942, 

The oceans: New Yorl\:, Prentice-Hall, Inc., 1087 p. 

.. . 

... 
J 

\. 

ARTICLE 34 B-87 

HYDROLOGIC STUDIES 

GROUND WATER 

34.. TRANSITORY MOVEMENTS OF THE SALT-WATER FRONT IN AN EXTENSIVE ARTESIAN AQUIFER 

By HAROLD R. HENRY, Lansing, Mich. 

The adjustment of the salt-water front in an extensive aquifer to a change in head in the salt water or the 

fresh water does not take place instantaneously. This 

article presents a mathematical demonstration that 

after a. eustatic change in sea level many thousands of 

years rrlfi.y be required for the salt-water front to reach 

a new position of equilibrium in an extensive aquifer, 

such fLS t:he Flor.idan aquifer of the Southeastern States. 

DERIVATION OF THE DIFFERENTIAL EQUATION 

For the aquifer shown schematically in figure 34.1, 

the one-dimensional form of Darcy's law is 

u= -~ cop+ pg oz) J.L ox . ox 

where u=velocity, k=specific permeability, J.L=viscosity, JJ=pressure, x=distn,nce along the n.quifer from the 

Witter table in the rechttrge area, p=density of Witter, 

g=nccelenttion of grnvity, and z=elevation ltbove sett 

level. The values of velocity and pressure nre continuous lteross the interfnce, whereas the density 

changes nbruptly from Po on the fresh-water side to p8 

on the Sttlt-wlit.er side. It is nssumed that the viscosity 

of St1lt water and fresh water are essentially equnl and 

thn.t the storage coefficient is 0. Integrating equation 

1 nnd rearranging terms yields 

1

'3_ ul + Ps- Po 7..--- y-- kpog Po 

J.L 

where fl=height of water table above sea level, l= 

length of nquifer from water table to outcrop on the 

ocm1.n floor and y=deptb below sea level to the interfu.ce. The rttte of the vertical component of movement 

of the interface or Stilt-water front is dyfdt=u sin a/8 

where a is the nngle of dip of the aquifer and 8 is the 

porosity of the ttquifer. For the snke of brevity thf' 

tirne pttrameter 

T 8l 

kpog cps-Po) sin a 

J.L Po 

is introduced. Equation 2 then tttkes the form 

--

dy + g--H --· Po 

d (T) Ps-Po 

l!"'IGURE 34.1.-Schematic sketcn ur an artesian aquifer with a 

salt-water front. 

SOLUTION FOR A STEP CHANGE IN SEA LEVEL OR 

ARTESIAN HEAD 

Let it be assumed that at a time t=O, H changes 

suddenly to a constant value which is rnaintained for 

all t>O. Such a change would be approximated in 

nature by a relatively rapid eustntic change in sea level. 

The variation of y is then given by the following solution of equation 3: 

1-e-tiT (4) 

where Yt is the value of y at t=O. Equation 4, which 

is plotted in figure 34.2, indicates that the rate of the 

asymptotic appronch of y to its equilibriurn value 

H (__!!!!___) is g0verned by the parameter T. 

Ps-Pu 

A· numerical example will clarify the relations involved. Consider an idealized artesian aquifer receiving recharge 100 miles inland, cropping out on the 

ocean floor 50 miles offshore, and having a seaward dip 

of 10 feet per mile. It is assumed that __EQ__=40, 

Ps-Po 

kpog =500 feet per day, and 8=0.15. These values are 

J.L 

not unlike those applicable to the Floridan aquifer of 

Florida and adjacent States. For these assumed 

conditions T= 13,800 years. It can be determined by 
B-88 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

inspection of figure 34.2 that at ~= 1, or n.fter a time 

lapse of 13,800 yen.rs, the snit front will have traveled 

only about 63 percent of the total distn.nce to its new 

equilibrium position. If the sudden change which 

occurs at t=O is, for exn.mple, a rise in sea level of 15 

feet, then the totn.l change to be expected in y is a 

decrease of 600 feet n,nd the total distance that the 

salt-water front will move inland is 60 miles. After 

13,800 years the front will hn.ve traveled only about 

3'8 miles. The time necessary for the front to travel 

90 percent of the total distance in this example is 

31,000 years. 

PLOT OF EQUATION 4 

0~----~----~------~-----L----~ 

0 

FIGURE 34.2.-The transitory movement of the salt-water front 

after a sudden cha.nge in sea level. 

35. ESTIMATING THE EFFECTS OF STREAM IMPOUNDMENT ON GROUND-WATER LEVELS 

By J. E. REED and M. S. BEDINGER, Little R.ock, Ark. 

Work done in coope·ra.tio·n wUh the U.S. A.nny, Corps of Nnginecrs 

The construction of reservoirs on streams that are 

hydraulically connected with aquifers results in a rise 

of the water table. This article describes an equation 

useful for estimating such changes in a semi-infinite or 

extensive aquifer. 

At many reservoir sites t.he change in stream stage 

upstream from the dam due to the impoundment is very 

nearly linear 'vith distance from the damsite. This 

linear change of head extends along the stream channel 

to the upper extreme of the pool. lJpstream fron1 this 

point., and at all points downstream from the dam, the 

r 

Change of head 

along stream 

Average water H 

depth at dam 

change in surface-\Yater stages due to impoundment can 

be considered negligible, or zero. These relations are 

shown graphically in figure 35.1. 

The distribution of head change in the aquifer caused 

by such a change in stream stages can be found by 

using the Fourier integral. Slichter (1899, p. 336) hn.s 

shown that the change of head (!1h) in a semi-infinite 

aquifer due to a change of head F(y) along the stream 

boundary is given by 

Length of pool 

a 

!1h=~J"' xF(z)dz 7r -"' xz+ (z-y)z 

o~----------~x~=~O~------------------------------------~~~----------- +-Downstream y-- 0 x=O 

y=a Upstream----. 

FIGURE 35.1.-Head change· along stream due to impoundment. 

\. 

_, 
..! 

>-

... 

ARTICLE 35 B-89 

where y represents distance along the strenm, x represents distn.nce norrnn.l to the stream, the dam is located 

n.t (x=O, y=O), n.nd z represents n variable of integration. The boundary conditions along x=O for the 

conditions indicn.ted on figure 35.1 mn.y be expressed as 

F(y)=O, O>y>a 

tl.nd 

Thus the in tegrn.l becomes 

1ia [ liz] X ~h=- H-- 2+( ) 2 dz, 1r o a x z-y 

from which we find 

h=~ [ (r-1-1!Y) (arctan ax Y +arctan~) 

hx I x2+y

2 

+-lo<"r . ' IJ 2a ee x2+ (a-y)2 (1) 

where ~h is the chn.nge in hen.d in the aquifer at point 

(x,y), l-1 is the change in stren.m stage at the dam, and 

a, is the length of the upper pool. The head-change 

distribution in it part of an n.quifer, determined from 

equn.tion 1, is given below. 

~ ().()(1 0.2ll 0.4ll O.fia O.Sa I.Oa. 1.2a I.4a 1.6a I. Sa 

1.211 •••• 0.00/T O.OSH 0. OSH 0. 09H O.IOH 0.09H 0. OSJ-1 0.08/1 O.OSH 0. 07ll 

1.011 •••• .001-l .lOH . 12/-/ .13H . 12!-l .lifT .JOH .09/f .OSH .OSH 

(1.811 •••• .20H .22fT .l9H .17H .16H .12H .III-I . 1l T-1 .09H .O~H 

o.na •••• .40H .:12H . 2(',ff .211-l . ISH .11/f .121-l .till .09H .09H 

0.4ll •••• .GOff .4:UJ .31H . 23fT . ]8/-/ . ISH .13f/ .111-l .IOH .OfJH 

ll.2n •••• .SOH . 47 fl . :ill1 .22fT . ISH .lfjJ-l .13/l .llH .lOl-l .09H 

O.Orr •••• I.OOH . 3:111 . 2M! .20fT . Hll-l .141-l .12fT .10H .091-l .091-l 

-0.2a •. .OOH .14/J .17/-/ .17fT .14/f .12/J .llH .101-l .091-l .08H 

-OA't •• .OOfl . Oil£·/ .IOH . 12/J .12!/ .lOH .10/J . 09f/ .OSfl .071-l 

-o.na .. .OOH .OIH .Oil-l .09/f .09H .091-l .09/I .OSH .081-l .OiH 

Few stren.m channels are straight enough to fit 

exactly the .idealized conditions indicated in figure 35.1. 

Thus, for example, estimates of head changes made as 

outlined will be in error if applied to the area near a 

meandering stream. At a great distance from the 

stream, however, irregularities in the stream path have 

tt negligible effect on ground-water level. Equation 1 

can be used in conjunction with an electrical n1odel to 

determine change in head near the stream. The head 

change at relatively large distances from and along n. 

line enclosing the affected portion of· the stream is determined from equation 1. The head change along the 

stream is known. Thus, the boundary conditions are 

defined over the perimeter of a sensibly small part of 

the aquifer with its irregular configuration along the 

stream channel. The head change may be estimated 

conveniently for the limited area of irregular shape by 

an electrical-model study. 

The method described above for estimating changes 

in the water table is based on the assumption that the 

flow system is in equilibrium. However, the water 

table is affected by several hydrologic agents that vary 

in time-a hydraulically connected stream, recharge 

fron1 precipitation, discharge by evapotranspiration, 

and pumping from wel1s. The action of these hydrologic agents precludes the esta.b1ishment of equilibrium 

in the _aquifer. However, water-table fluctuations due 

to these agents may be averaged, and this average may 

be used to identify a qua.si-equilibrium configuration of 

the water table that results from hydrologic conditions 

existing before construction of the dam. The ~tverage 

water-table configuration to be expected a long time 

after the reservoir is filled can be determined by simply 

adding the estimated change to the quasi-equilibrium 

configuration observed before construction. This addition is valid provided filling of the reservoir does not 

materially change such factors as the average stream 

stage above and below the pool, or the recharge and 

discharge rates through the area of the aquifer, and 

provided the flow through the aquifer may be defined 

by linear differential equations . 

REFERENCE 

Slichter, C. S., 1899, Theoretical investigation of the motion of 

ground wnters, U.S. Geol. Survey, 19th Ann. Rept., 1897-98. 

I)t. 2, p. 295-384 . 
B-90 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

36. MOVEMENT OF GROUND WATER BENEATH THE BED OF THE MULLICA RIVER IN THE WHARTON 

TRACT, SOUTHERN NEW JERSEY 

By S. M. LANG and E. C. RnoDEHAMEL, Trenton, N .• T. 

Work done in cooperation with the New Je1·sey Depa1·tment of Consm·vation anrl Econmnic Develo1nnent, Division of Water 

Policy and Supply 

The 'Vharton Tract, ·which includes about 100,000 

acres in the Pine Barrens region of southern New 

,Jersey (fig. :36.1), was purchased by the State in 1954 

as a water reserve t~ meet future requirements in the 

Camden and Atlantic City regions. An aquifer test 

was made by the Geological Survey n,t a site on the 

Mullica River, about 2lj2 miles northwest of the village 

of Batsto to determine the hydrologic characteristics 

of the water-bearing sands and the degree of hydraulic 

continuity behveen the sands and the ~1ullica River. 

The test results indicate the feasibility of developing 

the water resources of the tract. by means of wells. 

'Vater-level data from an extensive network of observation wells in the test. site were evaluated and reported upon by Lang ( 1961). The evaluation indicated 

that ground water moves toward the river from the 

upland areas on either side and discharges to the river 

in two major areas. 

In addition to the observation wells, a network of 

nine lines of piezometer tubes "·as installed in the 

streambed to detect ground-water movement immediN 

1 

0 10 20 30 MILES 

l!""IGURE 3().1.-Map of southern New Jersey showing location of 

Wharton Tract (crosshatched). 

ately below the bottom of the river (fig. :36.2). Each 

piezometer tube was especially fabricated of a regular 

11;4 -inch well point with a 1j2 -inch-long screen to allow 

for point determinations of pressure head. At each 

site, 2 piezometers were installed, 1 with the screen 1 

foot below the streambed and 1 'vith the screen 2 feet 

belo'v the streambed. ' 

The discharge of ground water to the river in two 

major areas as indica;ted 'by the well data was corroborated by an analysis of data from the piezometer 

tubes. This is shown by an evaluation of the eli tference 

in the water levels (head differential) in the shallow 

and deep piezometers (fig. 36.2). The greater head 

differential in the vicinity of lines 5 and 9 results in 

a much larger vertical than lateral gradient, indicating 

that ground water discharges to the stream at these 

sites. Figure :36.3 shm,·s the distribution of head as 

.nu~a.sured in the sha.llow piezometers. The pntten1 

indicates movement of 'Yater in the direction in which 

the strean1 is ftmving; however, because of the small 

head differential, the actual dmvnstream gradient is 

very low compared to the gradient for lateral movement of 'vater to the stream. Figure :16.4, showing 

the distribution of head in the deeper piezometers, 

shows centers of maximum piezometric pressure and 

indicates possible lateral movement in this lower level 

both upstream and clownstrean1 from these centers. 

The piezometer levels were compared with the streamgage height, a record of which 'vas obtained from the 

stage recorder on the west bank south of line G. This 

showed that the water level in both the shallow nncl 

deeper piezometer tubes stood highei· than the stream 

level. This factor plus the pattern of he:td differentia Is 

shown in figure 36.2 indicates that the general pattern 

is one. of upward movement of water from the de~per 

to the sha.llo'v piezometer horizon and thence to the •: 

river, with most of the discharge in the vicinity of lines 

5 and 9. 

The only area in which a downward gradient was observed is in the vicinity of the middle piezometer sites 

on line 9, where the head in the shallow piezometers is 

higher than that in the deeper ones. This is in part the 

re~ult of turbulence in the stream produced by the 

backing up of water by protruding bed materials immediately north of line 9. 
.. 

~ . 

•• 

... 

ARTICLE 36 B-91 

N 

1 

EXPLANATION 

1 .... 

Line of piezometers 

Stage recorder 

0 50 FEET 

lf'IOUHI~ 3(i.2.-Mnp of the Wluutou Tract piezometer field showing lines of equnl difference in water level (head differential) 

hetween shnllow nnd deeper piezometer levels on .June 9, 1960. 

Contom· interval 0.1 foot. Numbers on lines of piezometers 

11re referred to in text. 

620660-62-----7 

5 

I 

N 

1 

EXPLANATION 

1 

Line of piezometers 

Stage recorder 

0 50 FEET 

FIGURE 36.3.-Map of the 'Vharton Tract piezometer field showing contours of water level in piezometers 1 foot below the 

streambed on June 9, 1960. Contour interval 0.1 foot; datum 

assumed. Numbers on lines of piezometers are referred to 

in text.· 
B-92 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

N 

1 

EXPLANATION 

. . . . 1. 

Line of piezometers 

Stage recorder 

0 50 FEET 

FIGURE 36.4.-Map of the Wharton Tract piezometer field showing contours of water-level in piezometers 2 feet below the 

streambed on June 9, 1960. Contour interval 0.1 foot; datum 

assumed. Numbers on lines of piezometers are referred tQ in 

text. 

The sinuous pattern of head differentia 1 follows very 

closely the obsen·ed channel flow in the river. IHueh 

of the flow was along: the west bank downstrean1 from 

line 9 and erossed over toward the east bank just downstream from line H. The natural scour that produced 

the ehannel ftow also produced the major areas of discharge to the stream. 

The principal conclusions ·from analysis of the piezometer data are: Locally there are marked differe11ces 

in head between the 1-foot and 2-foot levels beneath the 

streambed, these head differences indicate important·. 

areas of upward movement of ground water to the 

stream, and the sinuous patterns of head differential and 

channel flow are the result of natural seour. 

REFERENCE 

Lang. S. l\1., 11:)61, Natural movement of ground wnter at a site 

on the Mullica River in the 'Vhnrton Traet, southem New 

.Jersey: Art. 313 ·i·n U.S. Geol. Survey Prof. Paper 424-D. 

p. D52-D54. 

I '· • :If ~~ 
.• 

~·, 

I .... 

, 

ARTICLE 37 B--93 

37. MOVEMENT OF PERCHED GROUND WATER IN ALLUVIUM NEAR LOS ALAMOS, NEW MEXICO 

By JoHN li. ABRAHAl\IS, Jn., Er...l\IER H. BALTZ, and 'VILL~Al\I D. PuRTY.l\IUN, Albuquerque, N. l\1ex . 

Wor1c (lone in cooperat-ion with the U.S. Atom·ic Energy Com.Jniss·ion 

The infiltration and underground movement of ::;nowmelt water in J\forhtndad Cnnyon near Los Alamos, 

N. 1\fex., were studied from l\{arch through ,June 1961. 

J\forhtndad Ca11yon is one of the deep, steep-walled 

ensterly draining canyons that dissect the Pajarito 

PlnJe:\.11. The part of the cnnyon studied has a drnina.ge area of nbout 2 square miles and heads at an altitude 

of about 7,350 feet on the central part of the plateau, 

where the annual precipitation is about 17.5 inches. 

The Bandelier Tuff of Pleistocene age caps the 

Pa.ju,rito Plateau and rests on the Santa Fe Group of 

middle ( ~) l\fiocene to Pleistocene (?) age. The principal ground-water body is in the Santa Fe Group about. 

!)60 feet beneath the canyon floor. IIowever, a small 

body of perched ground wn,t:er, which was the subject of 

investigation, occurs in alluvium resting on the Randelier in the bottom of J\fortandad Canyon. In the v;estern part of the c~myon the. a.lluYium is 40 to 80 feet 

wide and 20 to 30 feet thick, whereas in the eastern part 

of the canyon the alluvium is 600 to 700 feet ''"ide and 

rna.y be as much ns 100 feet thick 

The water in the alluvium was monitored by 1neans 

of holes drilled in seven lines across Mortandad Canyon. 

At en.ch line (fig. :37.1), 1 observation well and several 

2-inch-diamete.r access tubes were constructed with 

plastic pipe. '~Tater levels were. measured periodically 

in the observation wells, and the moisture content of 

the alluvium a,nd underlyi11g tuff was determined by 

using a neutron-scnJtet·ing· moisture probe in the access 

tubes. 

The source of recharge to the aJluvium in l\{ortandad 

Canyon is local precipitation. In 1961 about onefourHl of the annual precipitation occurred in the 

winter, and a snowpack 1 to 2 feet deep accumulated in 

the deep, narrow western p:nt, of the. canyon. Some 

diurnal melting occutTed il'1 .January, 'February, and 

l\'[:trch, and the melt water infiltrated the. soil and 

:t11uviurn. As the length of the. daily melting period 

increased in April, the thin alluvium in the upper pa1t 

of the canyon .became saturated to the level of the 

stream channel, and surface flow began because. the 

alluvium was mutble to absorb and transmit all the 

snowmelt water. 

Infiltrn.tion occurred at the front of the surface 

stream and in the channel upstream from the front; 

however, the ft·ont of the stream advanced eastward 

WEST 

.. 

1 Front of stream receding "' 

g westward, Apr.27.196l ~ 

.0~ Front ~f stream ad· j .~ ~ vancmg eastward, o; _ 

o Mar. 27, 1961 \ ~ 1 

l ~i o._ 

Qj 

31: 

c 

0 

1 

0 

Bandelier Tuff 

DATUM IS MEAN SEA LEVEL 

Front of stream 

advancing east· 

/ 

ward, Apr. 10, 

1961 

./"" Eastern limit of 

I flow in channel 

Apr. 17, 1961 

EAST 

6860' 

6820' 

6780' 

6740' 

6860' 

6820' 

6780' 

6740' 

FIGURE 37.1.-Longitudinal profiles showing base and top of 

alluvium and water levels in alluvium in part of l\iortandad 

Canyon. 

more rapidly than did the front of the zone. of complete 

saturation in the alluvium, as shown by the fact that 

the front of the stream passed test well Sa (fig. 37.2) 

almost 2 weeks before the water level in the well indicated that the alluvium was saturated to stream level. 

Between observation wells 4 and 6, where. the canyon 

widens, the alluvium thickens and consists of an upper 

unit of coarse, loose sand and an underlying unit of 

sandy clay. In this reach the. part of the ground-water 

body in the. coarse sand beneath the channel formed a 

mound with a steep eastward-sloping front. This happened because the coarse sa11d absorbed water from the. 

stream and transmitted it downward at a faster rate 

than the sanely clay absorbed the water and transmitted 

it laterally. "Tater filtering downward in the coarse 

sand beneath the eastern part of the stream was acCl'eted to the front of the ground-water mound, causing 

the front of the. ground-water mound in the. coarse sand 

to adva.nce eastward faster than the movement of the 

ground-water body as a whole.. 
B-94 GEOLOGICAL SURVEY RESEARCH 1962 

s 

6860' 

6840' 

6820' 

6800' 

6780' 

Access 

tube 6A 

Upper part of 

Bandelier Tuff 

EXPLANATION 

Access tube 60 

40 0 

L...LL..LJ 

Access 

tube 6B 

~~·'-.June 15, 1961 

Access 

tube 6C 

60 0 I I I 

ID 

Qj 

~ 

c: 

0 

.. 

~ Q) 

Ul 

.0 

0 

Access 

tube 60 

40 0 

L..l....L.J.... 

Access 

tube 6E 

20 0 LLJ 

Upper part of 

Bandelier Tuff 

N 

6860' 

6840' 

6820' 

April May June 

6800' Hydrograph 

showing 

change in 

water level 

6760' 0 10 20 30 40 50 FEET 

in observation well 6. 

Circles show 

position of 

water level 

during I I I I I I I 

DATUM IS MEAN SEA LEVEL 

May 24, 1961 \.--J April 12, 1961 

~.: 

Bar scale shows percent moisture by 

volume. Where May and June curves 

coincide with April curve, only solid 

line is shown. Where June curve 

coincides with April curve, only dashed 

line is shown 

periods of 

measurement in 

access 

tubes 

FIGURE 37.2.-Profile across Mortandad Canyon showing water levels and moisture content of alluvium an~ Bandelier Tuff in the spring of 1961. 

Late in April the front of the stream receded upstream as the snowpack in the upper part of the canyon 

was depleted. The front of the ground-water mound 

began to decay and flatten because it no longer received 

recharge directly from the stream (water level for 

April 27, 1961, on profile 1, fig. 37.1). Subsequent 

changes of the water levels resulted from continued 

lateral subsurface drainage of ground water from the 

upper part of the canyon to the lower part (profile 2, 

fig. 37.1). 

The moisture content of. the Bandelier Tuff immediately beneath the alluvium increased slightly. The 

highest recorded moisture content was 19 percent by 

volume (access tube 6B, fig. 37.2); this is probably less 

than the m1n1mum value necessary for significant 

amounts of water to be ti~ansinitted through the tuff. 

Perched 'vater was not found in the Bandelier Tuff or 

in the Santa Fe Group above the principal zone of 

saturation at test well 8, indicating that little or no 

water is moving downward from the alluvium to the 

main aquifer in the part of the canyon studied. 

The phenomenon of the building of a ground-water 

mound during infiltration and the different rates of 

movement of the resulting water strata probably occurs 

elsewhere. This possibility should be considered in 

other infiltration investigations, especially in the inte~·pretation of rates of water movement, use of tracers, 

and studies of chemical quality of water. 

... 

(.._ 

' 
... 

ARTICLE 38 B-95 

38. SOURCE OF GROUND-WATER RUNOFF AT CHAMPLIN CREEK, LONG ISLAND, NEW YORK 

By E .• J. PLunowsin and· I. H. I{ANTROWIT'".l, Mineola, N.Y. 

Worlc done in coopet·ation with Sttf!olk County Board of S1tpervisors aml S·uffolk County Water Autho?'ity 

Streams on the south shore of Long Island flow in 

shallow valleys across a gently sloping, highly permen.ble glacial-outwash plain. The st.rea.ms seldom overflow their banks and their sustained low flow indicates 

relatively sinall surface-water runoff and large groundwater runoff. More than 95 percent of all streatnflow in 

southwestern Suffolk County originates as discharge 

fl'om the ground-water reservoir. 

The ground-water reservoir consists of about 1,500 

feet of unconsolidated deposits of Cretaceous and 

Pleistocene age, which are subdivided hydraulically 

into a shallow unconfined aquifer and two confined 

aquifers. The shallow aquifer is recharged directly 

by precipitation. The confined aquifers are recharged 

from the overlying shallow aquifer by water that moves 

downward through the confining beds in the recharge 

nren. in the central part of Long Island. North and 

south of this recharge area, ground water a.t first moves 

roughly parallel to and then upward into the shallow 

aquifer. 

Seventy percent of the discharge from the grmmdW!tter reservoir is ground-water runoff; the remainder 

leaves the area as ground-water outflow to the sea. 

Because the regiomtl movement of ground water suggests dischttrge near the south shore of Long Island in 

the latitude of Champlin Creek, the increment of 

ground-water runoff per unit of channel length, defined 

as pickup, t-heoretically should increase uniformly from 

source to mouth. 1-Iowever, seepage investigations on 

several streams indicate that the pickup is greatest 

along their middle reaches and is substantially lower 

downstream. The purpose of this study was to determine the cause of the observed pattern of streamflow 

pickup. 

Champlin Creek was selected for study because it has 

no tributaries, pondage, or major regulation a.bove the 

gaging station at Islip. Discharge measurements 

rnnde periodically nt eight. sites along the stream were 

correlated with the gnging-stn..tion records to estimate 

discharge for each site. ''Tater levels w·ere measured 

in shallow wells installed adj~tcent to, and in, the stream 

chn.nnel. 

The pickup in menn annual discharge, computed for 

t'.he reaches QebYeen stream-gaging sites and expressed 

in cubic feet per'second per 1,000 feet of channel length, 

is shown in figure 38.1. The high pickup in the reach 

between Beech Street and Islip Boulevard may be attributed to increased lateral ground-water discharge, 

to upward movement of 'Yater from within the groundwater reservoir, or both. 

To determine the relative amount of lateral groundwater discharge, shallow wells were driven along three 

lines oriented approximaJely at right angles to the 

. stream. These lines, labeled A, B, and 0 on figure 38.2 

cross the stream at the Poplar Street, Beech Street, and 

Islip Boulevard gaging .sites (fig. 38.1); 4 wells are 

located along each line, 2 on each bank of the stream. 

Average water-table gradients, defined by the mean 

slope between pairs of outer and inner wells, were 0.7, 

0.8, and 1.8 feet per 1,000 feet along lines A, B and 0, 

respectively. Thus, the steeper water-table slope along 

line 0, illustrated by the sharp reentrant of the 16-foot 

water-table contour (fig. 38.2), corresponds to the reach 

of greatest streamflow pickup. The uniform slope of 

Champlin Creek (fig. 38.1), in combination with the 

natural convex profile of the wa.ter table, results in an 

increase in hydraulic gradient between the aquifer and 

the middle reaches of th~ stream. Moreover, the relatively hilly land surface between lines B and 0 may result in a. slightly higher water-table altitude and cause 

a further inci·ease in the hydraulic gradient. 

That steeper w'ater-table gradients result in greater 

lateral ground-water discharge can be ii1ferred from 

figure 38.3. Each plotted point represents the average 

altitude of the water table in 12 wells near the stream, 

plotted against concurrent dischn.rge at the gaging station. The wells are on lines A, B, and 0 and are 400 to 

1,600 feet from the stream. All measurements were 

made during periods of dry weather; thus the stream 

discharge is virtually all ground-water runoff. Because the altitude of the stream surface remains relatively constant, water-table fluctuations indicate changes 

in the hydraulic gradient toward the stream. Figure 

38.3 shows that as the water-table altitude, and hence 

the hydraulic gradient, increases, ground-water runoff 

inereases also. Therefore, part of the increase in 

streamflow pickup noted between lines B and 0 is 

caused by the steeper gradients of the water table, which 

result in a sharp rise in lateral ground-water discharge. 

'Veils driven directly into the strea.mbed on lines 
B-96 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

60' 

40' 

20' 

Great South Bay 

Series of ponds 

Source 

SEA LEVEL~0~==------~2---------4L---------6L---------8~--------1~0--------~1~2--------~1~4--------~----

0ISTANCE, IN THOUSANDS OF FEET, UPSTREAM FROM MOUTH 

2.0 

a:: 

~w (/) UJ 1.5 LL.LL. 

ua 

~ ~ 1.0 

0.:~ =>o 

~ ~ 0.5 

ll. 

"C 

'-

(Q 

>.-. 

.!!u 

:::::1 Q) 

0 c: CD·-

a.:::;. 

iii 

A 

B 

.... 

Q) 

Q) 

+'!X) '- -- (/)Q) 

~c: 

()·-

cv~ 

Q) 

CD 

J;'wonE 38.1.-Stream vrofile (A_) and pickup in mean annual disehurge (B) of Champlin Creek. Lines referred to in B are 

shown in figure 38.2. 

A, B, and 0 were used to determine the relative amount 

of upward ground-water movement into the creek. All 

wells "\vere screened in the uniform glacial-outwash deposits of the shallow unconfined aquifer. At each site, 

driving was stopped about every foot for the first 10 

feet and about every 5 feet thereafter, the well was 

pumped, and observations of head were made after the 

water had returned to its static level. The head as indicated by water levels in the wells increased from about 

equal to the stream stage when the bottom of the well 

was just below the streambed, to half a foot higher than 

the stream stage at a depth of 5 feet. The head remained the same at depths between 5 feet ~lnd 60 feet, 

where driving was terminated. 

These differences in head indicate that in the upper 

zone of the aquifer, ground water moves toward the 

stream both laterally and from below, but that below 

this upper zone the movement is predominantly horizontal under the regionn,l hydraulic gradient. 

The stream acts as a. ground-water drain that causes 

a reduction in hydrostatic head adjacent to its channel. 

The hydraulic gradient thus established between the 

aquifer and the stream induces water to flow toward 

the stream. The limiting distance froni which water 

moves toward the stream, both laterally and from below, 

is controlled by the interrela,tion of the hydraulic 

gr:adient between aquifer and stream, and the pernieability of the aquifer. Because the stream is shallow, most ground water discharges through the streambed. 

In summary, the rate of ground-water runoff is contro1led largely by the height of the water table adjacent to the stream. Ground-watet• movement into the 

stream channel along the middle and upper reaches of 

Champlin Creek is principally lateral, with little or no 

upward flow reaching the stream from deep within the 

aquifer. 

"-: 
t 

.. 

AR~rJCLE 39 B-97 

N 

1 0 4000 FEET 

:wnlUHI~ 0H.:!.-\Vnter·-hthle <.:ont"our·~, in feet above mean SNl 

lt~Yel. in thl' Chlllllplin Urt>ek art:>n. Dots rern·esent location of 

ollSPI'\'Ilt·ion wpll~. lilll'~" A. U. and 0 nt·e ch~scrihed in text. 

...J 

UJ 

> UJ 

...J 

<( 22.2 UJ 

(/) 

z 

<( 

UJ 22.0 ~ 

UJ 

> 0 21.8 CD 

<( 

1-

UJ 

UJ 

·LL 21.6 

z 

u) 

...J 

...J 21.4 UJ 

~ 

z 

...J 21.2 

UJ 

> UJ 

...J 

0:: 21.0 UJ 

1-

<( 

~ 10 UJ 20.8 

(.!) 0 <( 

0:: I UJ 

> <( 20.6 

4 5 6 7 8 9 10 15 

DISCHARGE, IN CFS, AT GAGING STATION 

.IJ"'IGURE 38.3.-Relation between average water level and disdutrge of Chn mvlin Cre~~k at Islip. IDH('h point represents 

the a ,·e.rage water level i 11 12 ohsen·ntion wells near the 

stream. 

39. RELATION OF FAULTING TO THE OCCURRENCE OF GROUND WATER IN THE FLAGSTAFF AREA, ARIZONA 

By ,J. P. AKEns, Tucson, Ariz. 

Worlc done in. aooperution with the Gity of Ji'laf}8fa.fj 

A,n investigation for additional water supplies for 

the city of :Flugstatf indicated that highly fractured 

rocks in the vicinity of mnjor fault.s transmit 10 to 50 

tirnes as much water as do the snme rod<:s where mt-

"fract"nred; wells tapping these fractured rocks have 

proport·ionnlly large yields. As a result. of the investigation, :) \\·ells were drilled along :faults near 'Voody 

~fountain, f) miles south west of Flagsta 1f, and near Lake 

~fary, () miles southeast of Flag-staff. 

A large part of. the sndace suiTotlllding Flagstaff is 

underlain by lava, f-lows and cinders of Tertiary and 

Qna,ternary age. The lava, ranging from 0 to at least 
B-98 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

600 feet in thickness, is underlain, in descending order, 

by sedimentary formations that. include the Moenkopi 

Formation of Triassic age, composed of 0 to 100 feet 

of red thin to thick beds of siltstone and sandstone; the 

J(aibab Limestone of Permian age, composed of about 

250 rto 350 feet of thick beds of yellowish-gray cherty, 

silty to sandy limestone;. the Coconino Sandstone and 

Toroweap Formation, undifferentiated, of Permian age, 

composed of about 800 to 900 feet of very light orange 

to gray well-sorted very fine to fine-grained quartz sand; 

and the Supai Formation of Pennsylvanian and Permian age, composed of about 1,500 feet of brick-red 

to brown thin to thick beds of siltstone and sandstone. 

The Moenkopi Formation was removed by erosion in 

many places near Flagstaff before the lavas were 

erupted, but the other formations are continuous 

throughout the entire area. Sedimentary rocks older 

than the Supai underlie the Flagstaff area, but they an~ 

beyond the practical reach of water wells. 

The Coconino Sandstone, sandstone strata in the 

upper 100 feet of the Supai Formation, and the lavas, 

where underlain by imp~rmeable beds, a.re the principal aquifers in the Flagstaff area. The other formations are relatively impermeable or are above the 

regional water table. 

The sedimentary rocks in the Flagstaff area were 

warped upward to form a broad, gentle arch before 

volcanism began. The Mormon ~fountain anticline 

(written communication, M. E. Cooley, 1961) forms 

part of the arch and extends 30 miles southeast from a 

point about 5 miles south of Flagstaff (fig. 39.1). The 

lava and the sedimentary rocks are offset by several 

large and numerous small high-angle faults which trend 

mainly north or northwest. 

Two of the large faults roughly bound the ~formon 

Mountain anticline in this area, and they and the anticline are the chief controls of the occurrence and movement of ground water in the area south of Flagstaff. 

The Oak Creek fault, west of the anticline, trends 

north, and its east side is downthrown as much as 500 

feet. The Anderson l\fesa fault., northeast of the anticline, trends northwest along the shore of Lake Mary, 

but swings to a north trend near the northwest end of 

the lake. It is downthrown on the west side about 400 

feet. Impermeable beds in the Supai Formation in the 

upthrown blocks are juxtaposed with the permeable 

Coconino Sandstone in the downthrown block by both 

faults. A small fault trending northwest on the north 

flank of "Voody Mountain cuts across the Oak Creek 

fault. This small transverse fault is downthrown on 

the southwest side. 

The rocks near t.he faults are intensely fractured 

and in places pulverized. The fracturing greatly increases the effective permeability of the rocks and facilitates recharge of the Coconino Sandstone through the 

lava and Kaibab Limestone. ,Joints are particularly 

abundant in the 1\:a.ibab Limestone between the small 

transverse fault near 'Voody ~fountain and the northwest-trending segment of the Anderson ~fesa fault. 

.Joints and faults in the limestone have been widened 

by solution, and several near the northwest end of J~ake 

Mary had to be dammed off because large quant-ities of 

lake ·water '"ere lost through them. The influence that 

these joints and the lake have on recharge is clearly 

shown by the ground-water mound indicated by the 

contours in figure 39.1. A similar n1ound near "'Toody 

~fountain suggests that a considerable amount of water 

from Rogers Lake enters the ground-water reservoir 

through the fractured zone paralleling the small transverse fault. A ground-water divide coincides with a 

line through thes~ mounds. . 

The ground water moves north and northeast and 

south in the Coconino and Supai from the divide until 

it reaches impermeable beds in the Supai Formation 

on the upthrm\'n sides of the Anderson ~fesa and Oak 

Creek faults. The altitude of the impermeable beds 

in the Supai Formation on the crest of the ~formon 

~fountain anticline is lower than the altitude of the 

water table. Thus, "·ater can move across the axis of 

the anticline. The water-table gradient is steeper 

northeast of rthe ground-water divide than it is southwest of the divide, mainly because the water moving 

northeast is in the Supai Formation, which is less permeable than the Coconino Sandstone throuo-h which . b 

most of the water moves southwest of the divide. 

Flagstaff city \Yell 1 was drilled near "'Voody Mountain on the dmn1thrown side of the Oak Creek fault 

to take advantage of the high permeability of the 

fault zone. The well is about 1,500 feet east of the 

Oak Creek fault and a little more than 2,000 feet from 

the small transverse fault. The well bottomed in the 

top of the Supai Formation at a depth of 1,600 feet. 

Aquifer tests of this well indicate that the "coefficient 

of transmissibility (expressed as the rate of flow of 

·water in gallons per day through a vertical strip of 

aquifer 1 foot wide extending the full saturated 

height of the aquifer under a hydraulic gradient of 

100 percent) of the Coconino at. the well site is 5,000 

gpd (gallons per day) per foot. The succeeding wells, 

2, 3, and 4, were located nearer the fault and they 

bottomed in the Coconino Sandstone at depths between 

1,516 and 1,746 feeL The coefficients of transmissibility 

obtained at t;hese \Yell sites-12,000, 20,000, and 50,000 

gpd per foot, respectively-indicate that the fractur-

....... 

·• 

:· 

( 

I 

~ 
., 

T. 

23 

N. 

T. 

22 

N. 

T. 

21 

N. 

T. 

20 

N. 

T. 

19 

N. 

ARTICLE 39 

~ '"" ,,,, \ 

f/1 :::. 11 1!1\l\1\1/lllllll\\1\~ 

111° 109" N 

0 

-.......=----~------i 32° 

50 100~~~-, ........ 

. R. 6 E. R. 7 E. 

EXPLANATION 

u 

0 

Fault 

U, upthrown side; D, do.wnthrown side 

Anticline 

q 

Spring 

0 sn2 

Well and altitude, in 

feet, Qf water table 

--6050--

Water-level contour 

Contour interval 50 feet; 

datum is mean sea level 

0 2 

'-..._0 5095 

R. 8 E. 

3 MILES 

l!,IGURE 39.1.-Mnp showing main structural features and water-level contours in the Flagstaff area. 

B-99 
B-100 · GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

ing, and hence the transn1issibility, increases toward 

the fault. A way from the fault zones transmissibilities generally are less than 1,000 gpd per foot. Similarly, the specific.:. capacity of wells completed in 

undistlp·bed Coconino ranges from a fraction to 1 gpm 

(gallon per minute) per foot of dra.wdown, "·hereas 

the specific capacity of the wells in the fractured fault 

zone near 'Voody Mountain ranges frorn 2.5 to 8.6 gpm 

per foot of drawdown. 

Hydrologic. conditions along the Anderson 1\1esa 

fault are similar to those along the Oak Creek fault, 

and the city of Flagstaff in November 1961 was drilling 

a well near Lake 1\1ary to ascertain whether similar 

high yields eould be obtained from wells "in tha.t area. 

40. METHOD FOR MEASURING UPWARD LEAKAGE FROM ARTESIAN AQUIFERS USING RATE OF 

SALT-CRUST ACCUMULATION 

By J. H. FETH and R. J. BRowN, Menlo Park, Calif., and Ogden, Utah 

Work done in cooperation with the U.S. Bm·eau of Reclamation 

Nearly 60,000 aeres of wet salt-encrusted barren land 

was exposed along the east shore of Great Salt Lake, 

Utah, during the period 1953-56 in an area underlain 

by aquifers that contain water under artesian pressure. 

A method was sought to measure the rate of upward 

leakage of the artesian water through the sodium-saturated elays that form the surface of the salt-encrusted 

barrens. 

The mudflats west of the Ogden Bay Bird Refuge 

were selected in 1954 as being representative of the area. 

The crust was removed from 3 plots, each having an 

area of 5 square feet, so that a ne·w layer of salt could 

accumulate. Then the new crust was removed, separated from the clay adhering to it, dried, and weighed, 

thus showing the amount of salt that had been deposited 

by evaporation of rising brine during a given period of 

time. Five determinations of rate of accumulation 

were made during"the study (see table below). 

The salt content of the brii1e was determined by digging a shallow well near the test plots and analyzing 

the water for its salt content. The brine was found to 

contain 93,000 parts per million of dissolved solids~ 

mostly sodium chloride, or 126.5 tons per acre-foot. 

From this information was calculated the amount of 

water evaporated to produce the accumulations of salt 

t-hat were collected and weighed. The rate of evaporation, in am·e-feet per acre, was calettlated on the basis of 

the eva.poration during the frost-free season of 160 days 

(Brown, 1960), inasmuch as the salt ernst does not form 

during the cold season. 

Evaporation pans were used to compare the nornml 

rate of evaporation of fresh water and the rate of evaporation from the salt crust. 

The average evaporation from the salt crust:. during 

the frost-free season was 0.04 acre-feet per acre (see 

table). This factor applied to the 60,000 acres of barRates of evaporation at and near the Ogden Bay Bird Refuge during the frost-free season of 1951,. 

Plot Period t Number of 

days 

Salt-crust tests Evaporation-pan tests 

Amount of 

salt accumu- lated (grams) 

Calculated Calculated 

potential Depth of water evaporated potential evaporation evaporation 

during 160 --------------- during 160 

days (acre-feet days (acre-feet 

per acre) Inches Feet per acre) 

Comparison 

of salt-crust 

evaporation to pan evaporation 

(percent) 

-------1-------------1------------1-----------------------

A ____________ June 30-.July 13_____________ 13 92 

B ____________ June 30-Aug. 2_____________ 33 70 

A ____________ July 13-Aug. 2_____________ 20 85 

C ____________ June 30-Aug. 24____________ 55 73 

B ____________ Aug. 2-Aug. 24_____________ 22 41 

Average ______________________ ---- _______ ------ _____ ----- ___ _ 

0. 09 

. 03 

. 05 

. 02 

. 02 

. 04 

5. 70 0. 48 

13. 37 1. 11 

7. 67 . 64 

21. 43 1. 79 

8. 06 . 67 

.5. 90 

5. 38 

5. 12 

5. 21 

4. 87 

5. 30 

1.5 

.6 

1.0 

. 4. 

. 4. 

1 Rainfall during the period June 30 to August 24 at rain gage adjacent to evaporation pan totaled 0.25 inches (July, 0.16; Aug., 0.09), and fell during several periods, none having an intensity of as much as 0.1 inches in 24 hours, and is considered negligible in its effect upon the experiments. 

........ 

.... 
+ 

,.. 

.. , 

.... 

ARTICLE 41 B-101 

ren land yields a h>htl en1porntion d isc.harge of about 

2,:'500 acre-feet of water. 

Aquifer leakage presumably continues during the 

cold senson, nlt:.hough the saH crust does not· form. The 

brine f-lows gradually lakeward or is mixed with lake 

wnt:er on occasions when a stTong west wind causes the 

lake water to move 1. ot· 2 miles east·.ward across the 

nearly level mudftnJs, n phenomenon the writers have 

observed several t·imes. Annual upward leakage, 

therefore, may be 865/l.GO of that caJcula.ted for the 

growing senson, or nearly 6,000 acre-feet per year. 

As the data obtained during the experiments of 1954 

showed very low rat·es of upward leakage, additional 

studies were made in 19:15. A tank was filled with 

saline c1a.y and n. bottom-feed systen1 install_ed. Brine 

from .n. shallow brine well was introduced into the feed 

system under· a few feet of head. The amount of brine 

moving upwnrd through t·he cla.y in the tank during a 

period of more t·han a. 1nonth was too small to measure. 

St·ill later, laboratory t-est·s on saline-mud cores from 

deposits of Great S:tlt J..~ake yielded rates of niovement 

of wn.t:er .in the range of O.OC>l to 0.00:3 foot per day. 

The authors believe, t·herefore, that the. average rate 

determined during the 1954 tests is probably in the 

proper order of magnitude and that clisturbance ·and 

puddling of the cla.y during its int-roduction into the 

experimental tank in the 1955 tests account for the fact 

that no movement was detected. 

Landward from the barrens, and at least locally lakeward under the brine-saturated clay, the aquifers of 

the area contain potable water. The location of the interface bebYeen fresh and saline waters is not known in 

the area of the experiments. It. is assumed, however, 

that fresh water moving lakeward from the motmtains 

furnishes the hydrostatic head that causes upward 

leakage and the resultant deposition of salt on the barrens. The mineral content is residual and is derived 

from bottom sediments laid down when Great Salt Lake 

was at a higher leveL 

So far as is known, the results hel'e reported represent 

the first attempt to measure rates of upward movement. 

of water through brine-saturated clay in the environment of an artesian system underlying n. saline mudflat. 

The results indicate that the movement is slow and the 

total loss by evaporation 'mensurable but small. The 

method probably could be applied to various "wet 

playa" areas in arid ttnd semiarid regions where artesian systems underlie mudflats on which measurable 

deposits of salt are accmnulating. 

REFERENCE 

Brown, Merle, 1960, Climntes of the Stntes-Utnh: U.S. ·weather 

Bur. Climatogrnphy of the United States, no. 60-42, 15 p . 

41. SEASONAL TEMPERATURE CHANGES IN WELLS AS INDICATORS OF SEMICONFI:N"ING BEDS· IN 

VALLEY-TRAIN AQUIFERS 

By STANLEY E. NORRIS and ANDREW M. SPIEKER, Columbus, Ohio 

1Varl,; rto·nc ·in COOJW'ra.t-ion ·wUh Ohio lJeJ)wrtm,ent of Nnt1wal Resom·ces, D·ivision of lVa.fet·, the M·iatni ConserV(I;IICJ/ District, 

anrl the Conunissione1·s of Hamilton C01mty~ Oh-io 

The most product:i ve aquifers in Ohio are valley-train 

deposits of sand and gravel in the principal ri,ver valleys. In many areas, the sand and gravel deposits are 

interbedded with "·ide-spread sheets of relatively impermeable till that retard recharge to the deeper wells 

and thus set practical limits on the quantity of water 

available from .induced infiltra.t-ion. 

A technique for determining the presence of interbedded till layers, based on temperature .logs of wells, 

·is described in Article 42. Another method of deterrn in i11g frorn water-temperature data the presence or absence of semiconfining beds is based on annual 

temperature fluctuations in wells. If two wells drilled 

in a. homogeneous and isotropic aquifer, and located at 

equal distances from a. source stream, receive replenishment principally from the stream, the temperature of 

the water pumped from the wells "·ill vary with seasonal changes in strean1 temperature. Temperatureversus-time graphs of the well water and stream water 

will ha.ve the same genera] shape. The amplitude of the 

fluctuations of the ground-water temperature will not. 

be as great as thnJ of stream temperature, and the sea.-
B-102 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

sonal high and low temperatures of the ground water 

will lag behind those of the stream. If the two wells 

are of unequal depth, differences in amplitude of the 

temperature fluctuations and in the time of arrival of 

seasonal highs and lows from the source stream will be 

apparent, but the curves will have the same general 

shape unless the inequalities of depth are very large. 

The presence in the water-bearing deposits of a semiconfining bed through which the water must leak, or 

around which water must flow to reach the wells, will 

change the shape of the ground-water temperature 

graph. If at the site of one well the flow of ground 

water is impeded by a semiconfining bed, the annual 

temperature graph for that well will be different from 

the annual temperature graph for another well where 

there is no semiconfining bed. The semiconfining bed 

will, in general, dampen the seasonal temperature 

fluctuations and produce a relatively flat graph. 

Figure 41.1 shows an example of the effect of a semiconfining bed on the seasonal temperature fluctuations in 

a well at the Tait Station of the Dayton Power and 

Light Co. in southern Dayton. Pumpage from the well 

field, chiefly replenished by infiltration from the Miami 

River is about 5 million gallons per day. The graph of 

the water temperature in well521, which is about 65 feet 

deep and screened above a sem.iconfining till bed, reveals 

seasonal fluctations much like those of the Miami River. 

In contrast, the temperature graph of water from well 

524, which is 155 feet deep and screened below the till, 

is nearly flat. That the semiconfining bed dampens the 

seasonal temperature fluctuations in well 524 is readily 

apparent. The effect is even more significant in view 

of the fact that well 524 is only 195 feet from the Miami 

River whereas well521 is 320 feet from the river. 

40~-----+------~------r-----~------~ 

t:: 

UJ WELL 524 

I 

z 60 UJ 

a:: 

I 

<( 

LL. 50 

en 

UJ 

UJ 

a:: 

(.!) 

UJ MIAMI RIVER 

0 

80 

70 

60 

50 

40 

1956 1957 1958 1959 1960 

FIGURE 41.1.-Temperature graphs of water in wells at 'the Tait 

Station of the Dayton Power and Light Co., compared to that 

of the Miami River. ''ren 521 tavs an unconfined upper r.one; 

well 524 taps a semiconfined lower zone. 

.... 
ARTICLE 42 B-103 

42. TEMPERATURE-DEPTH RELATIONS IN WELLS AS INDICATORS OF SEMICONFINING BEDS IN 

VALLEY-TRAIN AQUIFERS 

By STANLEY E. NORRIS and ANDREW M. SPIEKER, Columbus, Ohio 

Wo1·k done in cooperation with Ohio Department ot Natural Resources, Division of Water, the Miami Conservancy Distdct, 

and the Commissioners of Hamilton County, Ohio 

vVidespread sheets of relatively impermeable till, interbedded with va.lley-tqtin deposits of sand and· gravel 

in the Miami River valley at Dayton, Ohio, retard 

recharge to many of the deeper wells and limit the qmtntity of water available from the induced infiltration of 

strettmflow. A technique for determining the prese11ce 

of these till layers, based on temperature-depth relations 

in wells, was developed by the authors during a waterresources investigation of the Dayton area. Another 

method for determining the presence of interqedded till 

htyers, based on seasonal temperature fluctuations in 

wells screened rtbove the till compared to those screened 

below, is presented in Article 41. 

If the circulation of ground water is rel~tively rapid 

near centers of pumping or sources of recharge, differences in temperature of water in aquifers separated by 

till of relatively low permeability may be large enough 

to be detected by sensitive thermistor-type therm~meters. The method is most easily explained by considering temperature gradients in wells drilled where each 

of three hypothetical flow systems prevails. The explantttion is simplified by specifying that the temperature 

of the water infiltrating fr01n a source stream is higher 

than the temperature of the water in the aquifer. In 

Ohio this condition commonly occurs in late spring arid 

summer. 

The simplest of the three hypothetical flow systems 

is that of a homogeneous and heavily pumped sand and 

gravel aquifer traversed by an infiltrating stream. The 

water temperature will decrease linea.rly with depth in 

an observation well that penetrates the aquifer between 

the stream and the discharging well (fig. 42.1A). 

Consider next an otherwise homogeneous aquifer in 

which a horizontal layer of till of small lateral extent 

(fig. 42.1B) is situated so tlutt some water that enters 

the discharging well passes down ward through the till, 

while the remainder flows around the till layer. The 

temperature gradient in the observation well will be 

approximately linear above and below the till, but the 

part of the graph representing temperatures below the 

till will be displaced relative to that above the till, in 

the direction of lower temperature. The position of 

the till layer is indicated by a pronounced "blip"· on the 

temperature-gradient line, caused by the colder water in 

the till. · 

The third hypothetical flow system consists of two 

aquifers hydraulically separated by a·laterally extensive till layer, through which all recharge to the deeper 

aquifer must pass (fig. 42.10). Under these conditions 

that part of the graph depicting temperatures beneath 

the till will be displaced relat1ve to that above the till 

by colder water in the till and in the lower aquifer. 

However, unlike conditions shown in the second example (fig. 42.1B), the temperature of the water beneath 

the completely separating till layer will be no highe~· 

than that of the water in the till. Thus the temperature in the observation well w~ll decline with depth, 

but the rate of decline will increase significantly in the 

till. 

On figure 42.2 are shown drillers' logs of wells 530 

and 531, at the Frank M. Tait station of the Dayton 

Power and Light Co., beside which a.re plotted the respective temperature gradients. The wells are in the 

south part of Dayton about 700 feet from the Miami 

River in a well field yielding about 5 million gallons 

per day. The measurements were made in ~Tune 1957, 

when the water in the Miami River was a.ppreciably 

warmer than the ground water, similar to the condition spe?ified in the discussion of the hypothetical flow 

systems. 

Except for the somewhat anamolous lower part of the 

temperature gradient curve for well 531, which suggests the presence of an unlogged till deposit, zones of 

colder water closely correspond in depth to deposits of 

till as logged by the driller, while warmer water is 

associated with the intervening or underlying sand and 

gravel. Had all the water entered the deeper aquifer 

by leakage through the till it would have been no 

warmer than the water in the till itself. The zones of 

warmer water in well 530 reach nearly the same maxim.tun temperatures, whereas the lower warm zone in 

well 531 is much cooler than the upper warm zone. 

This indicates that the movement of water fron1 the 

shallower to the deeper aquifer was taking place more 

rapidly in the vicinity of well 530, where the till is 

absent locally, than in the vicinity of well531, where the 

flow was chiefly by leakage tJwough the till. 
B-104 GEOLOGICAL SURVEY RESEARCH 1962 

Observation 

well 

Discharging 

well TEMPERATURE 

Warm infiltrating 

stream 

0 0 

o · o/ ~ I . \ '\ . o Water • 0 

o' o 0 

. 0 0 0 0 ,. . \· 0 0 ,. 0 o.O o.,o.O o\.o'· o.o 

0 

0 0 . 0\ 0 " ·' 

0 0 '\ 0 ·' 0 ............ 

0 0 ~· 0, . ., 0 

Typical flow paths\ o_ o ·.~ o. 0 ~ ._:.,_ •

0 

0 0 0 • 0' . 

~ .,. 0 0' 0 0 

0 

0 

0 0 0 

0 • .......___ 

0 ' 0 0 0--- o.,o.·o 'o 0 

0 • 0. :-----.: 

0 

level 

0 0 . () . 

Sand and 

0 gravel 

0 

0 0 

0 0 

~ 

0 0 

0 

..c 

...... 

a. 

Q,) 

'0 

t:l.O 

c 

·v; 

ro 

Q,) 

u 

c 

l 

Colder 

~ 

A. Water flowing in homogeneous aquifer results in linear graph 

0 0 

0 

0 

0 

0 

0 

0 

0 

0 

0 • 

0 

0 

0 

0 

0 

' 

B. Colder water in discontinuous layer of till results in "blip" on graph 

0. -

/ "..::::- -.:::: ~ - / 0 • 0 ~. 0 '"" .............. 0--0 ~ -~ 

0 • Cl ·~ 0. 

\ 0 

0 0 

0 

-

' 0 

'~ D 

0 

,, 0 0 . ' 0 

0 ...__ 

~.!._ 0 0 

0 0 ---- 0 

C. Aqu,Hers completely separated by till results in displacement of temperature-gradient curve 

Warmer 

~ 

FIGURE 42.1.-ldealized ground-water circulatory systems, showing characteristic temperature gradients resulting 

from infiltration of warm watet· into a relatiYely cool aquifer. 

.~; 

r· 
..... 

;. 

·< 

r 

_.,. 

·~ 

700'-

6001

-

WELL 530 

tfO 60 • 0. 

0 0 ,D. 

0 0 

a· 

I)' 0 

·0. 

0 0 

. 0· 

0 0 

·~· 

I) 0 

·o. 

o·o 

• 0. 

O·o 

·0. 

0•0 

. 0. 

DEGREES (F) 

53 54 55 56 57 58 59 

I I I I I I I 

ARTICLE 42 

11-1<~------ Distance between wells, 228 feet 

D'O 

.D 

Do 

.o. 

0 0 

·0. 

oo 

·o. 

" 0 ·O, 

, 0 

·". 

45 

90 

138 

144 

160 

DEGREES (F) 

53 54 55 56 57 58 59 

I I I I I I I 

EXPLANATION 

~ 

~ 

Sand and gravel 

~ Till 

IO/o71 

~ 

Gravelly till or poorly 

sorted sand and gravel 

Shale 

l!"IOURE 42.2.-Drillers' logs of two wells near the Miami River and temperature graphs of the wells for 

June 11, 1957. Temperature anomalies show that the gronnu water partly flows around discontinuous 

deposits of till in moving from shallow to deeper aquifers. 

B-105 
B-106 GEOLOGICAL SURVEY RESEARCH 1962 

43. WATER-YIELDING POTENTIAL OF WEATHERED CRYSTALLINE ROCKS AT THE GEORGIA 

NUCLEAR LABORATORY 

By J. W. STEWART, Atlanta, Ga. 

Work done in cooperation with the U.S. Atomic Energy Commission and the U.S. Air· Force 

Metamorphic crystalline rocks underlie the Georgia 

Nuclear Laboratory in _the Piedmont physiographic 

province of Georgia, about 45 miles north-northeast of 

Atlanta. The area is capped by a mantle derived from 

deep weathering of quartz-mica schist, biotite schist, 

quartz-mica gneiss, and amphibolite gneiss. The mantle consists of a soil zone 1 to 2 feet thick, a zone of 

highly weathered rock ca1led saprolite that retains the 

structure of the parent rock, and a transitional zone 

between the saprolite and the unweathered rock. The 

saprolite consists almost entirely of alteration products 

derived from the weathering of minerals similar to 

those now found in the underlying rock, and its composition and thickness vary from one rock type to 

another. 

The direction and rate of ground-water movement 

in the saprolite are influenced by the degree of weathering to which the matedal has been subjected, by the 

mineral compqsition of the parent rock, by the orientation of the mineral grains, and by the presence of shear 

zones, quartz veins, and joints. Bedding and foliation 

in the laboratory area dip about 50° to 70° SE. except 

in the northern part, where they dip 20° to 30° SE. 

The parallel arrangement of the .mica crystals impedes 

the movement of water across the schistosity but favors 

movem~nt parallel to it. 

The permeability of samples taken parallel to the 

schistosity from the upper part of the saprolite is 25 to 

100 times greater than that of samples taken normal 

too~ at an angle to the schistosity. Consequently most 

ground-water movement is along the plane ofschistosity. 

In the upper part of the saprolite, below the soil 

zone, the grain-size distribution at 2 sites is 45 and 

49 percent sand and rock fragments, 35 and 40 percent 

silt, and 20 and 11 percent clay, respectively. The 

change in grain-size distribution between the saprolite 

and the soil is abrupt. 

The clay-size fraction of the saprolite consists m~inly 

of kaolinite, biotite-vermiculite, muscovite, and gibbsite; the silt-size fraction mainly of kaolinite, quartz, 

muscovite, biotite-vermiculite, and garnet; and the sand 

and rock fragments largely of quartz, biotite, and 

feldspar. 

Figure 43.1A shows the results of laboratory tests for 

porosity and specific yield of core samples collected at 

1-

z 

LLJ 

60 

50 

40 

~ 30 

~ 

20 

10 

10 

LLJ 

0:: 

u 

c( 

0:: 

LLJ a· 

a.. 

(/) 

z 

0 

...J 

...J 

c( 6 (!) 

u... 

0 

(/) 

z 

0 4 

::::i 

...J 

~ 

~ 

u.i 2 (!) 

c( 

0:: 

~ (/) 

0 

c 0 

0 Porosity"'-. 0 

--.,. -a, 0 

~-~--f.--'-

~ g 0 0 ~, 0 0 0 - .. 

\ 

\ 

\ 

~ 0 \ 0 0 0 \ ~0--

-- ~-~ 0 \ ~ 

0 .. '"'\-..J 0 

0 ' \ 0 ' 0 \ 0 0 ~, \ -, ' s·r·;c y;r /, '· \ ' ', 10 20 30 40 50 60 70 

DEPTH, IN FEET 

A 

00 10 

SATURATED THICKNESS OF SAPROLITE, IN FEET 

B 

FIGURE 43.1.-Results of laboratory tests on core samples of 

saprolite from the Georgia Nuclear Laboratory area. A .. 

Porosity and specific yield; B, total water in storage and 

water potentially ayailable to wells. 

-'!; 

-~ } 

-. 

_c),-'· 

-. 

ri 

,. 
·{ 

I 

~-

ARTICLE 43 B-107 

different depths below the ]and surface. The porosity 

of the sa.prolite is grea.test-as much as 54 percent-at 

depths of 30 to 40 feet, but decreases with depth as 

sapro]jte grades into unwea.thered rock. The porosity 

o:f. the unweathered rock is a:bout 5 percent, or about 

one-ninth the average porosity of the saprolite. The 

specific yield. determined from the same samples decren.ses with :incrensing depth, and.the amount of water 

in storage below ttbout 40 feet decreases markedly. The 

average speci fie yield of the saprolite is about 21 percent and ranges from about 28 percent in the upper part 

o:f the saprolite to 0 :in unweathered rock. 

Figure 43.1/J compa.res the total water in storage in 

a 70-foot saturn,ted thickness of the saprolite and the 

wa.ter that :is available by gravity drainage based on 

laboratory values of porosity and specific yield. 

The quantity of water stored in the upper 35 feet of 

629660--62----8 ' 

_ a water-saturated saprolite 1 acre in area is about 5.4 

million g~tllons, of which about 2.5 million gallons, or 

46 percent, could be recovered by wells. The. amount 

of water between the depths of 35 and 70 feet is 3.5 

million gallons, of which about 1.1 million gallons or 

31 percent is available to wells. The quantity of water 

stored in the lower zone is 35 percent less than that in 

the upper zone, and the water available to wells is 56 

percent less. 

For all practical purposes the specific yield of the 

unweathered rock is zero. The rock is compact and the· 

pore spaces are so minute that capillary forces virtually 

prevent movement of water. As a result, very little if 

any water stored in interstitial pores in fresh rock is 

available to wells. Most of the water available to wells 

in hard rock occurs in joints, bedding planes, cleavage 

planes, and other openings. 
B-108 GEOLOGICAL SURVEY RESEARCH 1962 

44. USE OF INFLATABLE PACKERS IN MULTIPLE-ZONE TESTING OF WATER WELLS 

By F. C. KooPMAN, J. H. IRwiN, and E. D. JENKINs, Denver, Colo. 

Packers have been used for many years in· testing 

and completing oil wells, but have not been used extensively in testing water wells. Recent developments 

in design now make the use of inflatable straddle 

packers feasible for testing sandstone and siltstone 

aquifers. One such test of aquifers of Permian to 

•Creta.ceous age near Las Animas, Colo., is described 

here. 

A test hole approximately 8 inches in diameter was 

drilled to a depth of 1,014 f~et through beds of Cretaceous to Permian a.ge (table 44.1) . Five zones, isolated by means of the packer assembly, were found to 

yield water. These zones included the Dakota Sandstone, the Cheyenne Sandstone Member of the Purgatoire Formation, part of the Morrison Formation, the 

Entrada Sandstone, and siltstones and sandstones of 

Triassic and Permian age. 

The packer assembly consists of an upper valve 

housing and two heavy-duty steel-reinforced rubber 

packer elements (fig. 44.1, A), separated by a "straddle 

pipe" (fig. 44.1, 0) 8 feet or more in length. A variety 

of packer elements are commercially available to fit test 

holes of various diameters. The spacing between the 

packer elements and the depth of setting are determined after evaluation of such geologic and geophysical information as electric, gamma-ray, hole-diameter, 

lithologic, and drillers' logs of the test hole. 

The packer assembly is lowered into the test hole on 

a suspension pipe (fig. 44.1, B). Four-inch standard 

steel pipe was used at Las Animas: The packer elements are inflated against the wall of the test hole by 

water under a pressure of about 850 to 1,250 pounds 

per square inch. Valve ports above, below, or between 

the packer elements are opened or closed by raising or 

lowering the suspension pipe. This permits water-level 

measurements, sampling, or pumping of the isolated 

zone between the two packer elements or of the composite zone above the top element or below the bottom 

element. When testing is complete, the packers may 

be deflated by turning the pipe. The assembly must 

be removed from the hole and fitted with a new blowout 

plug if it is to be set at a different level. The packer 

assembly can be reset and reused many times or can be 

installed permanently in a well. 

Drilling fluid and free sediment are removed by the 

"air lift" method from the zones to be tested. In the 

tests at Las Animas, yield and transmissibility of each 

aquifer were deterll).ined, and water samples were 

·collected for chemical analysis (table 44.2). A sub-

..... . . 

..... · . 

....... 

. .. ... . . . . . . . . . . . . 

. . ·. 

FIGURE 44.1.-Straddle-paeker assembly. A., pacl.:er elements; 

B, suspension pipe; C, straddle pipe. 
-( 

~-

ARTICLE 44 B-109 

T ABI .. E 44.1.-Generalized section of the stratigraphic units penetrated in test hole near Las Animas, Colo. 

System Geologic unit Thickness Physical character Depth intervals of water (feet) bearing zones (fc('t)-

Graneros Shale 79 Dark-gray to black gypsiferous shale with thin layers Not water bearof bentonite. in g. 

Dakota Sandstone 133 White to brown fine-grained sandstone, thin- to mas- 79-212 

sive-bedded; contains beds of clayey to sandy 

Cretaceous shale. 

Kiowa Shale lVIem ber of the 48 .Gray to black calcareous shale, thin-bedded; con- Not water bearPurgatoire :Formation. tains some thin-bedded sandstone beds. ing. 

Cheyenne Sandstone Member 137 White to buff fine-grained sandstone. 260-397 

of the Purgatoire Formation. 

Morrison Formation 132 Green, red, and reddish-brown mudstone, siltstone, 447-452 

and sandstone; contains some thin limestone beds. 

Jurassic Middle unit of Jurassic age 135 Red, orange-red to brown siltstone and very fine Not water beargrained sandstone; orange chert beds at top; con- in g. 

tains some limestone and gypsum. 

Entrada Sandstone 86 Buff to reddish-brown very fine grained sandstone. 644-750 

Triassic Triassic beds (Dockum Group) 180 Orange-red to red siltstone, mudstone, and very fine 750-930 

grained sandstone. 

Permian Permian beds 84+ Red to reddish-brown siltstone and fine-grained sand- 930-1,014 

stone. 

m.ersible pump cn.p:tble of pumping 20 gallons per 

minute a.t a. lift of 500 feet was used to pump from each 

aquifer while it was .isolated by the straddle packer. 

Depths o:f water were measured before, during, and 

:tfter pumping from ench aquifer. The effects of intern,qu ifet.· ]en.kn.ge were observed by means of measurements of water level i11 a smaH-dia.meter tube lowered 

past. the packer ele.ments prior to their ~nflation. 

~{ensurements were made in the tube simultaneously 

with measurements made in the zone isolated by the 

packer assembly. 

Aquifer 

Dakota Sandstone ________ 

Cheyenne Sandstone Member of the Purgatoire Formation oo ___________ 

Part of Morrison Formation and part of Entrada. Sandstone ______________ 

Basal part of Entrada 

Sandstone and Triassic sandstone ______________ 

Permian sandstone ________ 

I Artesian flow. 

The aquifer-test data were analyzed by the nonequi-

]ibrium method a.nd ~-tre summarized in table 44.2. The 

test near Las Animas proved that only the aquifers in 

the Da.kota and in the Cheyenne Sandstone ~{ember of 

the Purga.toire Formation were suitable for development, because deeper zones had very low transmissi-. 

hility and contained water of very poor quality. 

TABI .. E 44.2.-Summary of aquifer tests in test hole near Las Animas, Colo. 

Saturated Depth to Average Specific Coefficient Coefficient \Vater Specific Interval tested thickness water be- pump- Draw- capacity Duration of trans- of perme- tem- conduct-

(feet) of perme- low land ing rate down (gpm per of pump- missibility ability perature a nee able beds surface (gpm) (feet) ft of draw- ing (hours) (gpd perft) (gpd per (oF) (micromhos (feet) (feet) down) ft2) at 25° C) 

--- ----

79-212 133 60. 0 27 73 0. 37 72 1, 200 9 65 1, 630 

260-397 114 61. 2 27 82 . 33 89 900 8 65 1, 660 

397-700 -------- (I) 2. 5 270 . 01 2 5 -------- 66 7, 260 

724-930 206 308. 4 7 48 . 15 6 100 .5 75 6, 700 

930-1, 014 84 296. 6 10 153 . 07 5 40 .5 75 7, 160 
B-110 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

SURFACE WATER 

45. ESTIMATING DAYS OF CONTINUOUSLY DEFICIENT DISCHARGE 

By C. H. HARDISON and J. R. CRIPPEN, Washington, D.C., and Los Angeles, Calif. 

The number of days the flow of a strea.m remains 

less than a given discharge (days of continuously deficient discharge), which is sometimes a factor in selecting an industrial site, can be estimated from frequency 

curves of annual low flow in States along the eastern 

seaboard. Data for preparing low-flow frequency 

curves are obtained as part of a routine program of 

analyzing records of streamflow by electronic computer 

and are more readily available than are similar data 

for days of continuously deficient discharge. 

The procedure for estimating days of continuously 

deficient discharge uses the low-flow frequency data in. 

the following manner. The ratio of the 120-day annual low flow to the 30-day annual low flow at the 2-:yea.r 

recurrence interval is taken from curves for specific 

stations, such as are shown in figure 45.1, and used as 

an index to enter the curves shown in figure 45.2. The 

ratio of deficiency discharge to annual low flow obtained from the ordinate of figure 45.2 is then applied 

to other low-flow frequency data taken from figure 45.1 

to obtain the results plotted in figure 45.3. 

The deficiency discharge shown as the ordinate in 

figures 45.2 and 45.3 is the discharge below which the 

·flow remains continuously for the number of days indicated. The annual low flow is the lowest average 

flow each year for the indicated number of consecutive 

days. Thus, by definition, the deficiency discharge of 

a given unregulated station at a given recurrence· inter500~----r-----r-----~----~--~----~---, 

u 

iii~ :::::10 100 

uu 

~ ~ 50 

wa::: 

C!'UJ 

a::: a.. < :I: ...... uw 

~~ Cl 

10 

5 

3~----~----~----_.----~--~----~--~ 1.03 1.2 2 5 10 20 50 

RECURRENCE INTERVAL, IN YEARS 

FIGURE 45.1.-l\Iagnitude and frequency of annual low flow, 

Frencn Creek at Carters Corners, Pa., 1913-52. Index ratio 

(120-day to 30-day annual low flow at 2-year recurrence 

interval) is 2.3. 

UJ 

(!l 

a::: 

c( 

:I:~ 

uo 

~_J 

0~ 

>~ uo 

Z-l 

Uc( ~ -· ~:::I 

UJZ 

cz 

~c( 

oo 

oli= 

c( 

0::: 

7 

6 

5 

4 

3 

2 

1~------------~~----_.----~--~ 

1 2 2.3 3 4 5 

INDEX RATIOC120-DAY TO 30-DAY ANNUAL LOW 

FLOW ATTHE 2-YEAR- RECURRENCE .INTERVAL) 

FIGURE 45.2.-Ratio of deficiency discharge to annual 

low flow for 7- , 30- , 60- , and 120-day periods at 

10-year recurrence interval as function of index 

ratio for 32 stream-gaging stations in lDastern 

United States. Dotted line represents index ratio 

for French Creek at Carters Corner (fig. 45.1). 

val is almost invariably higher than the annual low 

flow for the same number of days. 

The curves in figure 45.2 are from least-square r.elations based on records at 32 long-term stream-gaging 

stations distributed as follo,vs: 

Alabama ----------- 2 New York ___________ 3 

Georgia ------------ 3 North Carolina ______ 5 

Indiana ------------ 5 Pennsylvania ------- 4 

Maryland ---------- 2 Virginia ----------- 5 

New Jersey--------- 1 'Vest Virginia-:------ 2 

Relation lines, between the lowest deficiency discharge 

for selected num~rs of consecutive days each year and 

the corresponding annual low flow, were established 

from the observed record at each of these stations and 

used to obtain the ratios used in the ordinate in figure 

·(· 

])-

'"'· 

~~ 

-~ 

( 
,. 

! 

.)oo 

ARTICLE 46 B-111 

200 

~0 .z 

~ 0 100 

0:~ c((J) 

J:o: 

(.)UJ !QQ. 

01- 50 

>UJ 

(.)UJ 

zu.. 

U.l(.) 

Qai 

U..::::l 

~(.) 

NUMBER OF DAYS FLOW REMAINS 

BELOW INDICATED DISCHARGE 

FIGURE 45.3.-Dnys of deficient discharge at the 2-year and 

10-year recurrence Intervals, French Creek at Carters 

Corners, Pn. Circles represent discharge computed from 

figures 45.1 and 45.2. 

45.2. The rn,tios used in the abscissa were obtained 

from low-flow frequency curves for each station such as 

n.re shown .in figure 45.1. 

The computations for obtaining the curve for the 

10-year recurrence interval in figure 45.3 are shown in 

the tn,ble below. 

7 days SO days 60 days teo day.~ 

10-year annual low flow from 

fig. 45.1, in cfs ______________ 9. 4 12 16 23 

Ratio of deficiency discharge to 

annual low flow from fig. 45.2 

for ar~ ttbscissa of 2.3 ________ 1. 16 1. 52 2. 27 3. 63 

10-year deficiency dischttrge, in 

cfs, by multiplication ________ 10 .. 9 18. 2 36. 3 83. 5 

~ 

The curve for the 2-year recurrence interval in figure 

45.3 was computed in the same manner using a set of 

curves for the 2-year recurrence interval similar to those 

shown in figure 45.2. The equations for the 10-year 

curves in figure 45.2 and the equations for the 2-year 

curves, whi~h ar~ not shown, are as follows: 

Length of period (days) 

7 _____________________ _ 30 ____________________ _ 60 ____________________ _ 

120 _____ ~--------------

Recurrence interval 

£-year 

y = 1.027 xo .158 

Y= 1.159X0.41a 

Y= 1.432Xo.7ao 

Y=2.20X0.958 

10-year 

y = 1.02XO .154 

Y = 1. 096X0 .384 

y = 1.30XO .660 

Y= 1.76Xo.854 

In these equations, Y is the ratio of deficiency discharge 

to annua1 low flow at the indicated recurrence interval, 

and X is the ratio of the 120-day to the 30-day annual 

low flow at the 2-year recurrence interval which is used 

as an index ratio. The standard error of estimate by 

these equations ranges from about 5 percent for the 

7 -day periods to about 20 percent for. the 120-day 

periods. 

Comparison of the standard errors of estimate of the 

results by the equations presented here and the standard 

error of the previously mentioned relation lines between 

observed deficiency discharge and observed annual low 

flow for each station shows that the results obtained by 

using the equations are more accurate than those obtained by using the relation lines when the relation lines 

are based on less than 15 years of record. For observed 

records longer than 15 years, the relations based on 

observed record give a more accurate estimate. 

The method presented here for estimating the number 

of days the flow of a stream can be expected to remain 

less than a given amount should be applicable to streamgaging stations in the States along the Atlantic seaboard 

from New York to Georgia. Data for 2 stations in 

Alabama and 5 in Indiana indicate that the. equations 

may be applicable as far west as the Mississippi River. 

46. DETERMINATION OF TIDE-AFFECTED DISCHARGE OF THE SACRAMENTO RIVER AT 

SACRAMENTO, CALIFORNIA 

By S. E. RANTZ, Menlo Park, Calif. 

Work done in coopcmtion with California Departntent of Water Resources 

The computation of momentary discharge of a tideaffected stream has been greatly simplified by the use 

of electronic computors (Baltzer and Shen, 1961), but 

the need still remains for a simple method for making 

reasonably accurate "on-the-spot" determinations of 

streamflow. A method of this kind is required, for 
B-112 GEOLOGICAL SU~VEY RESEARCH 1 9 6 2 

12-,000 r-----,----,------,-----,---~ 

Measured discharge 

1.5 .___ __ _,.L ___ L_ __ _J_ ___ l_ _ __j 

12m. 6 p.m. 12 p.m. 6 a.m. 12 m. 6p.m. 

September 30 October 1 

FIGURE 46.1.-Stage and discharge of the Sacramento River, 

Sept. 30 to Oct. 1, 1959. 

~xample, i~ the op~ration of a sewage plant discharging 

Its effluent Into a tide-affected stream. The coaxial correlation method described in this article fills this need 

in that readings from a pair of stage gages can be used 

to determine momentary discharge directly from a set 

of curves. 

The coaxial rating curves that were developed are 

based on 302 measurements of discharge of the Sacramento River at Sacramento, Calif. To obtain these 

data, a series of about 25 measurements was made 

during the course of each of 12 daily tidal cycles in the 

years 1957 to 1960. Measured discharges ranged from 

4,060 cfs (cubic feet per second) to 19,300 cfs. 

The streamflow measuring section is at the site of 

the stage recorder in the city of Sacramento; the auxiliary stage recorder is 10.8 miles downstream near the 

town of Freeport. Local inflow into the 10.8-mile reach 

of channel is negligible. The reach itself is located far 

enough upstream on the Sacramento River estuary. so 

that no reversal of flow occurs. When upland flow 

(streamflow) into the estuary is less than about 30,000 

cfs, however, ~he discharge is affected by tidal action,' 

and the flow In the reach is unsteady. The relative 

magnitude of the tidal effect in the reach increases with 

decrease in the upland flow and with increase in the 

range of elevation between high and low tides. The 

stages at Sacramento and Freeport during a 36-hour 

period and the fluctuation of discharge at Sacramento 

illustrate a typical low-flow condition (fig. 46.1). The 

upland flow above Sacramento was 9,300 cfs. As a resu~t of tidal effect the discharge at Sacramento varied 

from 6,800 cfs to 11,300 cfs. 

The differential equations of unsteady flow were used 

to devise a graphical technique for determining discharge. The following parameters serve as indices of 

the terms that appear in these differential equations: 

Dependent variable.-Measured discharge at Sacramento. 

Independent variables.-( 1) Stage at Sacramento, 

(2) fall in the reach between Sacramento and 

Freeport, and ( 3) the algebraic average of the 

change in stage observed at Sacramento and 

Freeport during a 15-minute interval. 

_Beca·use of the differential form of the equations of unsteady flow, there is no statistical model on which to 

. base the relationship of these variables. A further complication arises from the fact that joint functions are 

involved, for interrelations among the independent 

variables affect the flow at Sacramento. The versatile 

statistical technique known as the coaxial method of 

graphical multiple correlation (Linsley, Kohler and 

Paulln~s, 1949, p. 650-659) was adopt~d for developing 

the rating curves for the Sacramento River. 

The coaxial graphical correlation that was the end 

product of this study is shown in figure 46.2. In the 

interest of simplicity only a few lines are shown in each 

family of curves. To use the graph, first, the curves 

in the upper left-hand group are entered with the stage 

at Sacramento and the fall in the reach; next, the curves 

in the lower left-hand group are entered with the average rate of change of stage in the reach; finally, the 

adjustment graph to the right is entered and the discharge is read. The adjustment graph was added to the 

correlation to introduce .a necessa.ry curvilinea~ity to 

the relationship. This curve may also serve another 

purpose-if the relationship should change, as a result 

of channel dredging, for example, only the adjustment 

graph need be revised~ thereby eliminating the laborimts 

task of revising the two families of curves. 

A graphical correlation of the type developed in this 

study, or a modification, should be useful for determining the momentary discharge for many streams, tidal 

or otherwise, that are subject to unsteady flow. 

REFERENCES 

Baltzer, R. A., and Shen, John, 1961, Computation of homogeneous flows in tidal reaches by finite difference method: 

Art. 162 in U.S. Geol. Survey Prof. Paper 424-C, p. 039-

041. . 

Linsley, R. K., Kohler, M. A., and Paulhus, J . .J. H., 1949, Applied hydrology; New York, McGraw-Hill. 

r" 
'\ 

ARTICLE 47 B-113 

~ 6.5~---r~~~---r--,-~--~--~~~-r-----r--~ 

~ 6.0 ~---+--~~~-+--~~tr---1------\---\---J------\--~ 

~ 

ci 

~ 5.0~--~~--~~~~--~--4&----~--~----+-+-~ 

UJ 

:E 

<( 

0:: 

~ 4.0 C/) 

I-

<( 3.0 1----+---------+:Y,.~--~~~--~rl--+-~r+-.L...---+---i UJ 

(!) 

<( 

1-

C/) z.o ~---+----------1-----~lo.--+~L---~~-----l...l..__ __ L-j 

DISCHARGE, IN CUBIC FEET PER SECOND 

8000 12,000 16,000 20,000 

]f'IOUJU~ 46.2.-Coaxial rating curves fol' the Sacramento River at Sacramento. Dashed lines and arl'OW illustrate use of the curves. 

the curves. 

47. POINTS OF ORIGIN OF PERENNIAL FLOW IN GEORGIA 

By WILLIAM J. ScHNEIDER, Washington, D.C. 

The Yellow River basin nea.r Snellville, Ga .. , which 

drains 1.34 square miles in the Piedmont province. northcast of Atlanta, and the Tired Creek basin near Cairo, 

Gn .. , which drains 55 sqwtre miles in the Tifton Upland 

of the Coastal Plain provjnce, are representative of a. 

large part of the State. The hydrology nnd physical 

charncteristics of these two areas in Ge01·gin. are being 

studied to establish criteria for accurate classification 

of stream channels on topographic maps as ephemeral 

or perennial. 

Field investigations of more than 200 small headwater 

stream valleys in both basins indicate that streamflow 

becomes perennial at sharply defined points, and 1.1.2 

such points were identified in the fidd. These points 

of origin of perennial flow are characterized by abrupt 

beginning~ of incised stream channels. The channels 

have semicircular heads with vertical walls. The depths 

of incision at the wall range from about 1. to 8 feet. 

The valleys just upstream from the channel heads are 

rather broad, flat flood plains that are covered. with 
B-114 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

Concave profile 

o~~--~--~--~--~----~--~---L--~ 

0 wo ~0 600 800 

HORIZONTAL DISTANCE, IN FEET 

FIGURE 47.1.-Types of stream -profiles in Yellow River basin. 

vegetation, generally woodland, and are areas of deposition of recent sediments. The geologic significance of 

these points of origin has not as yet been investigated. 

Estimated flows up to 4 to 5 gallons per minute were 

observed issuing from small pools at the bases of the 

vertical channel heads; Because observations of flow 

were made at selected- sites at several times during the 

low-flow season, it is reasonable to assume that streamflow below the sharply defined points of origin is 

perennial. 

Not all first- or second-order headwater streams become perennial, however; some remain ephemeral 

throughout· their length. These ephemeral streams 

can be identified by the shn pe of their longitudinal profile. l\feasured longitudinal profiles of 16 headwater 

streams in the Yellow River basin can be grouped according to upward concavity or convexity. A typical 

profile for each group is shown in figure 47.1. 

Streams that are ephemeraJ throughout their length 

to their junction with a perennial strean1 have generally 

con~ex profiles; streams that become perennial at a 

spring issuing from a well-defined seepage face at the 

head of ,an incised channel have generally concave profiles in their ephemeral reaches. Ordinarily, except in 

densely wooded areas, the type of longitudinal stream 

profile can be determined from stereoscopic viewing 

of aerial photographs, thus giving a practical method 

of delineating these points of_ origin of perennial 

streamflow. 

QUALITY OF WATER 

48. DETERMINATION OF BORON IN WATERS CONTAINING FLUORIDE 

By JACK J. RowE, Washington, D.C. 

Many investigators have reported that fluorine interferes in colorimetric determinations of boron. Gaestel 

and Hure (1949) found it necessary to complex fluorine 

with A1Cl 3 during the methyl borate distillation prior 

to the determination of boron colorimetrically with 

curcumin, and Ryabchikov and Danilova ( 1950) used a 

resin to separate boron from fluorine for the determination of boron with carmine. Sher ( 1957) also reported that fluorine concentrations of as little as 2.5 

ppm interfere ·in the quinalizarin or alizarin S. methods 

for the determination of boron in waters; Cogbill and 

Yoe (1957) reported that fluorine must be absent for 

the colorimetric determination of boron using anthrarufin, quinizarin, or diaminochrysazin. . Ellis and 

others (1949) reported that' fluorine in concentrations 

greater than those usually found in plants will cause 

low results in the dianthtrimide determination of boron. 

Later, Powell and Poindexter (1957) and Langmyhr 

and Skaar ( 1961) also reported that fluorine will interfere in the determination of boron with dianthrimide. 

Rain water and Thatcher ( 1960), in their modification 

of the dianthrimide method, did not study the effect of 

fluorine. The present study was made to determine 

the fluorine tolerance of this method. 

Apparatus and reagents 

Oven, ooo C. Uniformity and stability of temperature control 

are critical. 

Absorption cells, 25-mm diameter. Boron-free glassware with 

glass stoppers was u.sed for digestions and development of 

the colors. 

Spectrophotometer, Beckman Model B. Blue-sensitive phototube, sensitivity setting 2, slit width appro~. 0.6 mm, wavelength setting 620JL. 
{ 

'· 

ARTICLE 48 B-115 

Sodium tetraborate standard solUJtion, 0.200 B~Os mg per ml. Dissolve 0.5477 g NfuJBc07·10 HaO in distilled water and dilute 

to lliter. 

Sodium tetraborate solution, 0.002 mg BaOs per m.l. Dilute 10 ml 

stnndnrd solution 0.200 mg n~oa per ml to 1 liter. 

1,1' <linnthrhni<le stock reagent. Dissolve 200 mg dianthrimide 

in- 50 ml cone 1-InSO.. Store in refrigerator in polyethylene 

bottle. 

1,1' dlnnthrhnide worldng reagent. Dilute 1 voltime of stock 

reagent to 20 volumes with cone HnSO.. Store in tightly 

closed polyethylene bottles in the dark. Reagent is stable 

for long periods. 

Sulfuric ncid, 95.G-00.5 percent, (sp gr 1.84) (Danielsson, 1959). 

Sodium fluoride, 1.000 mg 1!"' per ml. Dissolve 2.21 g NaF in 

distilled water, dilute to 1 liter. . 

Sodium fluoride, 0.10 mg 1!.., per mi. Dilute 10 ml 1.000 mg 

F per ml to 1liter. 

Procedure 

1. Pipet a volume of the sample containing less than 0.012 

mg B203 into the absorptiQn cell. 

2. Prepare a blank of distilled water and sufficient standards. 

Adjust volumes to about 5 ml. 

8. Add 1.0 ml cone H2SO.. Mix by swirling. 

4. Evaporate overnight in an oven at 90° C. At end of evaporation the volume should be about 1.0 ml. 

5. Add 5.0 ml dlantbrimide worldng reagent and mix by 

swirling. 

6. Incubate for 4.0 hr at 90° C. 

7. Cool and dilute with 10.0 ml cone H2SOc. 

8. Stopper and mix by swirling. 

9. Olean the exterior surfaces of the tube. 

10. Determine the a·bsorbancy of the sample and standards 

agninst the blank nt 620m p.. 

EFFECT OF FLUORINE ON THE DETERMINATION 

. OF BORON 

Standards.-The effect of fluorine on the determination of boron was studied by adding 0.010- to 1.000-mg 

quantities of fluorine to standards containing 0 to 0.010 

mg of B20s at step 2 of the above boron procedure. The 

procedure was then followed through step 10; optical 

densities are shown in truble 48.1. The optical densities 

were determined in the absorption tubes used :for the 

digestion, hence optical densities are reported to only 

two decimal places. The addition o:f up to 1.000 mg 

of fluorine does not affect the dianthrimide-horon color, 

as can he seen from table 48.1. 

N aflural waters.-A study was also made of the effect 

of adding 0.010 mg of fluorine to samples of water from 

Yellowstone National Park. Water samples were first 

analyzed for boron using the above procedure. To 

equivalent samples of Fhe water, 0.010 mg of fluorine 

and 0.002 mg o:f B20s were then added, and boron again 

determined. It was found that the originally determined boron, plus the added amount, was recovered in 

each case, as shown in table 48.2. 

TABLE 48.1.-E.ffect of fluorine on dianthrimide determination 

of boron 

MgB203 Mo F added Optical densit.TJ llfg B203 llfg F added Optical 

dens it!! 

o _________ 0 0 0. 030 0. 96 . 010 0 . 040 . 95 . 050 0 . 050 . 97 . 100 0 . 075 . 95 

0.004_ ---- 0 . 47 . 100 . 97 . 010 . 47 . 150 . 97 . 020 . 47 . 200 . 97 . 030 . 475 . 500 . 96 . 040 . 48 1. 000 . 95 . 050 . 47 0.010 _____ 0 1. 18 

0. 008 _____ 0 . 95 . 020 1. 19 . 010 . 96 . 030 1. 18 . 020 . 95 . 050 1. 18 

TABLE 48.2.-E.ffect of adding fluorine and boron to water samples 

from Yellowstone National Park 

MgB203 MgF 

Sample Description Total No. Origi- Origi- MgB203 

nally in Added nally in Added 

sample sample 

---· ----------

4_ -- ·----- Cinder PooL _________ 0. 0073 0.002 0.005 o. 0095 

5_- ------- Echinus Geyser _______ .0053 .002 .006 .0073 

10_ ------- Porcelain Terrace_---· .0055 .002 0.010 .0054 }}_ _______ Pork Chop PooL _____ .0062 .002 .006 .0083 

18 __ ------ Excelsior Geyser_----- .0066 .024 .010 .0067 19 ________ Artemisif\ Geyser ____ ._ .0134 .002 .022 .010 .0152 

20_ ------- Daisy Geyser _________ . 0215 .002 .028 .010 .0235 21_ _______ Pool near Daisy_. _____ . 0245 .002 .002 .010 .0265 

BEHAVIOR OF F'LUORINE 

A study was made of the behavior of fluorine in the 

concentrated sulfuric acid medium employed for the 

dianthrimide determination of boron. Standards were 

prepared containing 0 to 0.500 mg of B20 3 and 0.500 to 

1.000 mg of fluorine and carried through steps 1, 2, 3, 

and 4 of the boron procedure. Fluorine analyses were 

made to determine whether any fluorine was still present' in the sample after the sulfuric acid evaporation at 

90° C and before the addition of the dianthrimide 

(step 5). The sulfuric acid concentrate was diluted 

and transferred to a distilling flask. The procedure 

of Grimaldi and others (1955) was used for the distillation and determination of fluorine with thoron. To 

check the method used for the determination of fluorine 

in the presence of boron, a control sample, containing 

0.400 mg of B20a, ~.000 mg of fluorine, and. 1 ml of 

concentrated sulfuric acid was placed in the distilling 

flask, and the procedure of Grimaldi and others (1955) 

used for the determination of fluorine was followed. 

All the fluorine present in the control· sample was 

recovered in the distillate. The results of this study 

are shown in table 48.3. 
B-116 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

TABLE 48.3.-Fluorine remaining after evaporation at 90°C with 

concentrated sulfuric acid 

l _________ _ 

2 _________ _ 

3 _________ _ 4 _________ _ 5 _________ _ 6 _________ _ 7 _________ _ g _________ _ g _________ _ 

ControL ___ _ 

0 

0 

. 010 

. 020 

. 050 

. 100 

. 200 

. 400 

. 500 

. 400 

Mo F added 

0. 500 

1. 000 

. 500 

. 500 

. 500 

. 500 

1. 000 

1. 000 

1. 000 

1. 000 

DISCUSSION 

Mo F after ovemioht 

evaporation 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1. 000 

(not evaporated) 

The study of the fluorine tolerance of the dianthrimide method of Rainwater and Thatcher showed that 

the suggested method could be applied to the determination of boron in waters from Yello,vstone National 

Park, some of which cont~in up to 30 ppm of fluorine. 

It can be seen from the data of tables 48.1 and 48.2 that 

the presence of as much as 1.000 mg of fluorine will not 

interfere with the determination of boron using this 

procedure. Although these data may seem to contr~­

dict the observations of Powell and Poindexter, who 

reported interference from fluorine caused by the complexing of boron with the fluorine, investigation of the 

behavior of fluorine during evaporation of the 

concentrated sufuric acid solution used for the borondianthrimide determination reconciled the apparent 

inconsistency. Powell and Poindexter and Langmyhr 

and Skaar measured the· effect of adding fluorine to a 

solution containing boron and dianthrimide but did 

not include an evaporation step. From the data of 

table 48.3, it can be seen that the fluorine is volatilized 

during the sulfuric acid evaporation at 90° C, thereby 

separating fluorine from the boron prior to the addition 

of the dianthrimide. Cogbill and Y oe, in their study 

of the determination of boron with diaminochrysa.zin, 

and other isomeric dihydroxy anthraquinones, found 

some indication of this behavior of fluorine. It would. 

seem, then, that under the conditions of the proposed 

procedure involving evaporation with sulfuric acid in 

glass tubes, the fluorine. is selectively eli1ninated, probably as silicon tetrafluoride as evidenced by the etching 

of the glass near the bottom of the absorption tubes 

used for the digestion. For the analysis of waters 

containing more than 10 ppm of fluorine, it is recommended that old tubes be used for the digestion and 

development of colors. Solutions should be transferred to clean tubes or cells for the final readings of 

the absorption. 

R:EFERENCES 

Cogbill, E. C. and Yoe, .J. H., 1957, Spectrophotometric determination of boron with diaminochrysazin, diaminoanthrarufin and tri1bromoanthrarufin: Anal. Chemistry, v. 29, p. 

1251-1258. 

Danielsson, L., 1959, A study of the conditions for the determination of boron with dianthrimide: 'l'alanta, v. 3, p. 138-

146. 

Ellis, G. H., Zook, E. G., and Baudisch, 0., 1949, Colorimetric 

determination of boron using 1,1' -dianthrimide: Anal. 

Chemistry, v. 21, p. 1345-1348. 

Gaestel, Ch., Hure, J., 1949, Colorimetric determination of microgram amounts of borates in presence of fluorides: Soc. 

~chim. France Bull., p. 830. 

Grimaldi, F. S., Ingram B., and Cuttitta, F., 1955, Determination of small and large amounts of fluorine in rocl{S: Anal. 

Chemistry, v. 27, p. 918-921. 

Langmyhr, F .. J., and Skaar, 0. B., 1961, The effect of foreign 

ions on the speetrophotometric determination of boron with 

1,1' -dianthrimide: Anal. Chim. Acta, , .. 2ii, p. 262-270. 

Powell, ,V. A., and Poindexter, K H., 1957, 1,1' -diantbrimide 

for spectrophotometric determination of boron: U.S. 

Atomic Energy Comm. Report CCC-1024-:'l~R-229. 

Rainwater, F. H., and Thatcher, I... I..., 1960, Methods for col-

~lection and analysis of water samples: U.S. Geol. Survey 

Water-·Supply Paper 1454, p. 113-115. 

Ryabchikov, D. 1., and Danilova, V. V., 1950, Determination of 

'boron and fluorine when present together: Zhur. Anal. 

Khim., v. 5, p. 28-31. . 

Scher, A., 1957, Rapid colorimetric determination of the boric 

acid content of water by means of quinalizarin and alizarin 

S.: Hidrol. Kozlony, v. 37, p. 168-170. 
ARTICLE 49 B-117 

49. LIMITATIONS OF THE METHYLENE BLUE METHOD FOR A~S DETERMINATIONS 

By CooPER H. WAYl\IAN~ Denver, Colo. 

Work done in cooperation with Federal .Tiou.sing Adm·inistration 

The anionic surface-active agent. a.lkylbenzenesu1fonat.e (ABS) is the most abundnnt detergent found in 

ground- a.nd surface-water supplies. The ABS aniOn 

is represented by 

[Gt:!}I2a-GJI4- SOH]- 1

• 

In water, the anion is exh·emely stable to both chemical 

n.ncl biochemica.l degradation.· 'Vn lton ( lDHO) recently 

reported ranges in ABS concentrations from 0.00 to 1.8 

ppm (parts per million) for surface-water supplies nncl 

from 0.00 to 10.0 ppm for ground-water supplies. 

All;hough t·he physiological implications of ABS to 

human beings is unknown, prolonged ingestion of this 

material by rats is believed to be nontoxic (Paynter, 

1960). Laboratory studies suggest that bacteria do 

not travel great distances in water-saturated sands 

containing .ABS (Robeck, 1961). Nichols and ICoepp 

(1D61) found that 'Visconsin ground water became 

more bacteriologically unsafe with increase in concentration of detergent. ~fi1ler (19Hl) indicated that 

certain .ingredients .in detergents cause pathogenic bacteria to flourish. The relationship between detergent 

pollution and bacteriological pollution of ground water, 

if any, has not been well established, but .ABS can be 

used as an excellent indicator of pollution. 

Because of the importance of ABS as an indicator of 

pollution, the limitations, precision, and accuracy of 

present methods available for its determination should 

be known. 1\iost analysts prefer to use the methylene 

blue method (American Public }lealth .. Association and 

others, 1960, p. 246-248) because of its simplicity. 

1-:Iowever, some laboratories use an infrared technique 

(Sallee and others, 1956) as a referee method. 

Both organic and inorganic materials interfere with 

the methylene blue method, which is nonspecific for the 

sulfonated benzene ring. Organic sulfates, sulfonates, 

carboxylates, phosphates, and phenols form complexes 

with methylene blue, a.nd inorganic cyanates, chlorides, 

nitrates,. and thiocyanates form ion pairs with this compound; other orgn.nics, such as amines, offer additional 

interference through competition with methylene blue 

for a. reaction. Because of these interferences and because some constituents might be present in surface- or 

ground-water supplies in amounts exceeding ABS concentrntions, determinations of ABS in natural water by 

the methylene blue method requires some reservations. 

Our experience with this method suggests that experimentnJ technique can contribute additional error. 

Therefore, deionized water containing a solid composed 

of 99.0 percent ABS was studied to determine the influence of. the following variables on the method: ( 1) 

Time-of absorbancy measurement after extraction, (2) 

type of methylene blue used, and (3) temperature. The 

colored complex that is formed decays with time. ·Figure 49.1 shows the change in absorbancy (A) with 

time ( t). At 10 ppm and 1.0 ppm, -dA/dt is 7 X 10-4 and 

2 X 10-4 absorba.ncy units per minute respectively. The 

complex is more stable a.t low ABS concentrations. Little error is introduced if the complex is measured within 

60 minutes after extraction. ~{any laboratories frequently extract 6 to 8 samples in an 8-hour clay, however, and measure the absorbancy at the end of this 

period; obviously, poor precision would be attained 

with such a technique. The type of dye used is extremely important. A dye that displays maximum 

absorb::mcy at the wavelength of interest should be used. 

Figure 4D.2 shows the change of absorbency for a variety of dyes in solutions containing 0.5 ppm and 1.0 

ppm of ABS. Of these dyes, Eastman P-573 or Fisher 

NA-652 give maximum absorbency and should be preferred with this method. Organic dyes may deteriorate 

with time, and the impurities contained from batch to 

batch may vary; these factors also should be considered 

in the choice of a dye. Temperature in the range from 

10° to 35°C has no apparent influence on the stability 

of the complex. 

The precisim1 of the method seems to depend on the 

eoncentration of ABS. The table below shows that 

tl\e standard error of estimate increases with concentration. Standard errors of estimate of 0.75+0.13 

Standard error of estimate of A BS at va.rious concentrations 

Standard error of estimate 

A BS Field samples Laboratory concentra- samples 

tion (ppm) 1---~--1--_:_-..,.---1 

Source Ppm Type of Ppm water 

0.10 .................. ----·---·--- ............ Distilled .... 0. O.'i 

Report 

Am. Public Health Service and 

others (1960). . 75 ............................................................... do ____ _ . 13 B. B. Ewin~ (written commu- nication, 1961). 

. 18 Am. Public Henlt.h Service and 

others (1960). 

2. 22 _________ ----·---·--- ·----- Tap ______ _ 

2. 50.................. ....................... ............ Deionized. . 30 

. 35 ................. --------·--- 0. 04 ------------ -·---- 1. oo _________ ------------ . 12 ---------·-- _____ _ 

1. 25 .. ________ ------------ .19 ------------ ------ ]. 31.. .............. River . 25 ----------·· ------ water. 

Wayman (this article). 

Cohen (1961) . 

Do. 

Do. 

Am. Puhlic Health Service and 

ot.hers (1960). 
B.:...l18 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

0.9 

- dA = 0.0007 = 7 X 10- 4 

dt 

> (.) 

z 

<{ 

III 

0::: 

g 0.3 

III 

<{ 

0.2r----· I --~-----~_j 1 ppm 

·- ~~··=0.0002=2X10- 4 absorbancy units per minute 

0.1 

0 40 80 120 . 160 200 240 280 320 

TIME, IN MINUTES 

FIGURE 49.1.-Infiuence of time of measurement on ABS absorbancy determination. 

ppm of ABS (B. B. Ewing, written communication, 

1961) and 2.50+0.30 ppm (from the subject study) 

can be cited. These data represent about 60 samples 

for each value reported. A detection limit of 0.025 

ppm is reported for ABS (American Public Health 

Association and others, 1960). Our studies of deionized water containing a solid composed of 99.0 percent 

ABS indicate that the detection limit is about 0.1 ppm 

of ABS. In a study of drinking-,vater supplies of 32 

cities throughout the Ui1ited States, the Association of 

American Soap and Glycerine Producers Committee· 

( 1961) reports that the average ABS content of the 

supplies was 0.024 ppm and that 98 percent of the 

supplies contained ABS in the range of 0.00 to 0.10 

ppm.. If the detection limit is 0.1 ppm of ABS in 

deionized water, of what significance are ABS concentrations of less than 0.1 ppm that are reported for 

natural water? For the methylene blue method, most 

analysts prepare calibration curves from solutions containing a solid that is equivalent to 60 to 70 percent 

ABS. If the remaining 30 to 40 percent of this solid 

contains ingredients that react with n1ethylene blue, 

additional error is possible; a standard containing 

99.0 percent ABS (prepared by the California Research Corp.) was used in the study described in this 

report. A calibration curve prepared from the purest 

standard available appears to be the most accurate.' 

IIow accurate are ABS determinations made by the 

methylene blue 1nethod? This procedure depends on 

the formation of a blue-colored salt when methylene 

blue reacts with ABS. Because the method is nonspecific with regard to ABS, other organic or inorganic 

ions in solution can influence the accuracy of a determination. Because ABS is resistant to chemical oxidation, recent investigators (Hill, Shapiro, and 

Kobayashi, 1961) have utilized chrome sulfuric acid 

as an oxidant to remove surfacta.nts other than ABS 

and other ions from solution before use of the methylene blue method. vVhen this oxidation step is used, 

the methylene blue method is less subject to interferences from inorganic ions and certain surfactants and 

it appears to be more accurate than the standard meth-
>- (.) 

z 

· ... { <( a:l 

0:: 

0 

C/) 

a:l 

<( 

·~· 

ARTICLE 49 B-119 

0.280.----.----.----.----~--~----~--~----~--------~---.----~---.----~---.------. 

0.260 

0.240 

0.220 

0.200 

0.180 

0.160 

0.140 

0.120 

EASTMAN KODAK P573 

FISHER NA-652 

FISHER NA-653 

FISHER A-766 

FISHER SO-M-78 

CONCENTRATION OF ABS, IN PARTS PER MILLION 

FIGURE 49.2.-Effect of dye type on absorbency determination .. 
B-120 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

ylene blue method. Another modification of the standard method ("\Vebster and Halliday, 1959) is reported 

to give results comparable to those for infrared for 

river water and sewage. Because of the purported improved accuracy of the two modified methylene blue 

methods, these methods should be investigated further 

or perhaps combined into a single method. 

Certain limitations regarding the precision, accuracy, and experimental technique in use of the standard methylene blue method are indicated. For those 

analysts making ABS deter1ninations on surfacewater, ground-water, and public-water supplies, concentrations of less than 0.1 ppm should be reported 

with some reservation. 

REFERENCES 

American Public Health Association and others, 1960, Standard 

methods for the examination of water and wastewater: 11th 

ed., New York, Am. Public Health Assoc., Inc., 626 p. 

Association of American Soap and Glycerine Producers, 1961, 

ABS in drinking water in the United States: Am. "\Vater 

'Yorks Assoc .. Jour., v. 53, p. 2~)7-300. 

Cohen, J. M., 1961, Detergent detection: The Sanitarian, v. 23, 

no. 4, p. 194-197. 

Hill, H. H., Shapiro, l\L A., and Kobayashi, Y., 19tH, Determination of alkylbenzenesulfonate in water: Am. Chern. Soc. 

Natl. Mtg., 140th, Chicago, 1!)61, DiY. of Water and 'Vaste 

Chemistry, Paper 5, 16 p. (presented Sept. 4) 

Miller, B. ,V., 1961, Syndets and pathogens: Am. "'ater 'Vorks 

Assoc. Ann. Mtg., Detroit, 1961 (Jlaper presented .June 6) ; 

Detroit l!,ree Press, June 7, H)6l. 

Nicholas, M. S., and Koepp, E., 1961, Synthetic detergents as 

a criterion of Wisconsin ground-water pollution: A.m. 

W'"ater 'Vorks Assoc. Jour., v. 53,}). 303-306. 

Paynter, 0. E., 1960, The chronic toxicity of dodecylbenzene 

sodium sulfonate: U.S. Public Health Service Conference 

on Physiological Aspects of "'ater Quality Proc., "\Vashington, D.C., Sept. 8-9, 1960, p. 17G-179. 

Robeck, G. G., 1961, Ground water contamination studies at the 

Sanitary Engineering Center: U.S. Public Health Service 

Symposium on Ground-"'ater Contamination, Robert A. 

Taft Sanitary Engineering Center, Cincinnatti, 1961. 

(paper presented at meeting) 

Sallee, E. M., Fairing, .J. D., Hess, R. ,V., and others, 1956, 

Determination of trace amounts of alkylbenzenesulfonate 

in water: Anal. Chemistry, v. 28, p. 1822-1826. 

"'alton, G., 1!)60, ABS contamination: Am. 'Vater Works 

Assoc .. Jour., v. 52. p. 1354-1362. 

'Vebster, H. L., and Halliday, .J .. 1959, Determination of alkylbenzenesulfonate in river waters and sewage: The Analyst. 

v. 84, p. 552--559. 

50. HYDROCHEMICAL FACIES IN THE "400-FOOT" AND "600-FOOT'' SANDS OF THE BATON ROUGE 

AREA, LOUISIANA 

By C. 0. MoRGAN and M. D. WINNER, JR., Baton Rouge, La. 

Work done iw cooperation with the Louisiana Department of PubUc Wo1·ks and the Depa1·t1nent of Conservation, Lo1tisiana 

Geological Siwvey 

The "400-foot'' and "600-foot" sands, t-wo major aquifers of the Baton Rouge area, Louisiana, crop out and 

are recharged in East Feliciana and 'Vest Feliciana 

Parishes north of Baton Rouge (Morgan, 1961). The 

principal artificial discharge area of these artesian aquifers is in the industrial district of East Baton Rouge 

Parish. 

The "400-foot" and "600-foot" aquifers in the re-

. charge area have been considered early Pleistocene by a 

nmnber of writers (Doering, 1958; Rollo, 1960, pl. 2; 

Morgan, 1961), whereas others have correlated equivalents of these sediments with the Citronelle Formation 

of Pliocene age (Stringfield and LaMoreaux, 19~7). 

The water-analysis diagram in figure 50.1 is modified 

after Back (1961, p. D-381), who described the ground 

waters of the Atlantic Coastal Plain in terms of hydrochemical facies (Back, 1960). In the investigation described herein, chemical analyses were 1nade of water 

from selected wells in an a.rea extending from the recharge area in East Feliciana and 'Vest Feliciana 

Parishes to beyoi1d the salt-water interface in East 

Baton Rouge Parish (fig. 50.2'). The chemical constituents are plotted ju percent of total eq-i.1ivalents per 

1nillion on the water-analysis di-agram (fig. 50.3). 

Analyses of water from the recharge area show the 

cation facies in the ground water to be Na,Ca and the 

anion facies to be Cl + S04 ,HCO:l. The pH of the 

ground water in this area usually is less than 6.0; the 

lowest was 5.2 (fig. 50.2, sample 5). This low pH is attributed to solution of C0 2 fron1 abundant decaying 

vegetation in the soil zone. Dissolved solids range fr01n 

a low of 27 ppm (parts per million) in smnple 4.to 83 

ji 

J'· 
-{ 

, ... 

."'-

ARTICLE 50 B-121 

\ I 

\I 

1\ 

I \ 

I \ 

I \ 

I \ 

I ~~I \ C). 

'~--I \ x 

ur& ~ X t£> 

I\ \ 17 I I 

I \ C). I \ 

I \ ~r& x..n I \ 

I r&" 9 \ ~ I u \ 1 ... ~ \ 

I \ I ~ \ \ I \ 1 u) \ I 

\ ~ v 

I \ I \ 1\ 

\ -5o I \ II 

\ ~ I \ e;r& I 

\ C). r&" I 

\ I x ~ \ I 

I t£> \ I 17 \ I 

1:: \, \ I 

co Y. ' u) \ '\ )( I~ o' "" 't:.tS> 0 \ I 

c:>) ," ul I 

\.X \ I ~ "f- \ I 

\ I 

\ I . \I 

A 

I \ 

Ji.,IOUltE 50.1.-)Vater-annlysis diagram showing hydrochemical 

fncies, in percent of total equivalents per million (after Back, 

1001). 

ppm in sam.ple 3. Presence of ground \Vater of a low 

pii in combination with a low dissolved-solids content 

:indicates that the recharge area is a highly leached zone 

(Back, 1960, p. 94). Accordingly, ground water in this 

area is of Na,Cn. :facies rather than Ca+~ig or Ca,Na 

facies as in recharge areas of the Atlantic Coastal Plain. 

As the CO:!-charged water moves down dip in the aqui-

:f:er, Ca and ~ig are dissolved in the extent that the 

wttter approaches a Ca,Na facies (fig. 50.3, sample 7), 

but this action is countered by cation exchange, which 

replaces the Ca. and Mg ions in the water with Na 'ions. 

The Na facies is reached near the area of the fresh 

water-salt water interface. 

The anion facies in the ground wat~r progressively 

changes down dip from a Cl + 804, HC03 facies through 

HC03, Cl + 804 to n. HC03 facies near the fresh watersalt water interface (fig. 50.2). Ground water in this 

part of the system is characterized by a pH between 7.0 

and 8.0 and a dissolved-solids content of 175 to 225 

ppm. 

At the fresh wa.ter-salt water interface, mixing is 

caused by pumping. The mixture is represented as a 

gradual cation change from the Na facies to the Na, 

Ca facies, and as a sharp anion change from the HC03 

facies to the Cl + 804, H C03 facies (fig. 50.3) . The 

change in facies over a period of time as the interface 

moves northward is illustrated by samples 15A, 15B, 

and 17 A, 17B, and 17C, which represent replicate 

samples fr01n wells 15 and 17. 

In summary, the recharge area of the "400-f<;>ot" and 

"600-foot" sands of the Baton Rouge area is a highly 

leached zone identified by ground water of an N a,Ca 

facies, low pH, and low dissolved-solids content. As 

the water moves slowly downdip its chemical character 

is altered-the dissolved-solids content increases and 

the water is softened by cation exchange. Mixing of 

salt water and fresh water at the interface causes a 

sharp change in the anion facies from HC03 to Cl + 

804, HC03. However, the cation facies change from 

Nu. to Na,Ca is less pronounced. 

REFERENCES 

Back, William, 1960, Origin of hydrochemical facies of ground 

water in the Atlantic Coastal Plain: Internat. Geol. Cong., 

21st, Copenhagen1960, proc., pt. 1, p. 87-95. 

--1961, Techniques for mapping hydrochemical facies : 

U.S. Geol. Survey Prof. Paper 424-D, p. D380-D382. 

Doering, J. A., 19iJ8, Citronelle age problem: Am. Assoc. Petroleum Geologists Bull., v. 4~, no. 4, p. 764-786. 

Morgan, C. 0., 1961, Ground-water conditions in the Baton 

Rouge area, 1954-59, with spec;ial reference to increased 

pumpage; Louisiana Dept. Conser.v., Geol. Survey and 

Louisiana Det)t. Pub. \Vorl\:s, \Vater Resources Bull. 2, 78 p. 

Rollo, J. R., 1960, Ground water in J.1ouisiana: Louisiana Dept. 

Conserv., Geol. Survey and Louisiana Dept. Public \Vorks, 

\Vater Resources Bull. 1, 84 p. 

Stringfield, V. T., and LaMoreaux, P. E., 1957, Age of Citronelle 

Formation in Gulf Coastal Plain: Am. Assoc. Petroleum 

Geologists Bull., v. 41, no. 4, p. 742--746. 
B-122 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

s 400'N ~-----RECHARGE AREA-----:-)-+~~(------- DISCHARGE AREA -----------i-1 

(East and West Feliciana Parishes) (East Baton Rouge Parish) 

200' 

200' 

400' 

600' 

800' 

EXPLANATION 

Em 

Cl + S04 , HC03 facies; low dissolved-solids content. 

HC03 , 

~ Cl + S04 facies 

HC0

-3 facies. 

Cl + S04 , HC03 facies; 

~ 

~ high dissolved-solids content 

5 

I 

Well sample point 

0 5 10 MILES 

Land surface 

Baton Rouge 

industrial area 

7 

FIGURE 50.2.-Generalized. north-south geologic section showing movement of ground water, areas sampled, and distribution of 

anion hydrochemical facies in the "400-foot" and "600-foot sands o~ the Baton Rouge area. Dashed lines show migration 

of the fresh water-salt later interface. 
-{ 

t 

629660--62--9 

ARTICLE 50 

EXPLANATION 

o5 

Well sample point 

as shown on 

geologic section 

Arrows in diagram indicate 

downdip hydrochemicalfacies changes 

FIGURE 50.3.-Water-analysis diagram showing hydrochemical 

facies, in percent of total equivalents per million, in the "400-

foot" and "600-foot" sands of the Baton Rouge area. 

B-123 
B-124 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

51. CATION HYDROCHEMICAL FACIES OF GROUND WATER IN THE ENGLISHTOWN FORMATIO~, NEW JERSEY 

By PAuL R. SEABER, Trenton, N.J. 

Work d,one in cooperat~on with the New Jersey Division ot Water Policy and Supply 

The sandy part of the Englishtown Formation of 

Late Cretaceous age has been utilized as an aquifer 

throughout approximately 1,100 square miles of the 

Atlantic Coastal Plain of New Jersey. The greatest 

ground-water development from this aquifer is in the 

shore communities of l\1:onmouth and Ocean Counties. 

The chemical cl1aracter of the water in the Englishtown Formation indicates a relation between topography of the coastal pl~in, the lithology, and 

ground-water movement (fig. 51.1). The concept of 

hydrochemical facies has been used by Back (1960) to 

demonstrate a regional relation between these same 

factors in the Atlantic Coastal Plain. 

A hydrochemical facies may be thought of as a diagnostic chemical aspect of ground water indicative of 

the relative proportions of the anions or cations. 

Variations in the relative proportions of Ca, Mg, Na, 

and I<: reflect environmental effects and can be used as 

diagnostic indicators of hydrochemical relations. 

Concentrations of I<: and Mg do not vary significantly 

in the Englishtown, but they are included to conform 

to the terminology previously used by Back ( 1961). 

HC03 is the predominant anion of the ground water 

in the Englishtmvn Formation; eye;n in the coastal area 

there is no indication of a high Cl content. The dissolved-solids content (residue on evaporation) of the 

ground water ranges from 14 to 243 ppm. 

The topographic highs of the coastal plain lie 5 to 10 

miles southeast of the outcrop of the Englishtown 

Formation (fig. 51.1A). The northern and southern 

topographic highs are separated by a topographic low. 

The Englishtown Formation, where exposed in the 

northeast part of the area, is a conspicuous unit of 

dominantly light-colored well-sorted medium-grained 

sand that is slightly micaceous and sparingly glauconitic and lignitic. The unit contains a few laminae 

and discontinuous lenses of clay and silt and some fine 

gravel. The formation thins southwestward along the 

strike, but appears to thicken do-\vndip. Minard and 

Owens ( 1960) suggest that most of the pre-Quaternary 

formations in the coastal plain of New Jersey have 

similar depositional characteristics. The sandy part 

of the formation forms a wedge that thins southwestwa.rd (fig. 51.1B). The sandy unit becomes increasingly clayey and silty and the sand becomes finer 

grained southwestward along ·the strike as well as 

southeastward downdip. In the southern part of the 

Atlantic Coastal Plain of New Jersey, the Englishtown 

Formation is composed entirely of clay and silt. 

The formation appears to be of continental and 

· deltaic origin in the northeastern part of the outcrop 

area, and of marine origin in the south. Groot and 

Glass (1960) reported that kaolinite is the predominant 

clay mineral in the nonmarine sediments and that montmorillonite is predominant in the marine deposits of 

the coastal plain. 

Recharge to the Englishtown occurs mostly by leakage from overlying sediments. The piezometric highs 

correspond to topographic highs (fig. 51.10), which 

are separated by a piezometric low that corresponds to 

the topographic low in the same area. The outcrop 

functions as a natural-discharge area throughout its 

extent. Increased pump age along the Atlantic coast has 

resulted in interception of most of the flow that formerly discharged through the submarine outcrop northeast of Sandy Hook Bay. A discharge area in the 

southern part of the system has not. been defined, but 

ground water may move upward into the overlying 

formations. 

The cation hydrochemical facies characterized by 

water of more than 90 percent Ca+Mg (in equivalents 

per million) forms a belt that corresponds to the topographic highs and the piezometric highs (fig. 51.1D). 

This facies results from solution of calcareous materials 

in the overlying formations by ground water, which 

enters the Englishtown Formation in the areas of the 

piezometric highs. Both updip and downdip from this 

belt the Ca cqntent is lower, updip the Na content is 

about the same. This presumably is due chiefly to infiltration of water that contains less Ca and about an 

equal amount of N a. Down dip to the southeast, the 

water contains more than 90 percent N a+ IC This 

cation hydrochemical facies results from ion exchange 

in which Ca of the water is absorbed by montmorillonite, 

and N a of the montmorillonite is taken into solution. 

The water contains more N a than could be released by 

exchange with the amount of Oa in solution in waters 

coming from areas of higher head. This indicates another source of Ca, presumably from solution of calcareous fossils at depth in the formation. The high 

proportion of N a in the ground water downdip from 

the recharge area suggests the presence of sodium mont-
,-

EXPLANATION 

~ Outcrop area of the 

Englishtown Formation 

0 0-100 feet > 100 feet 

Elevation above meon sea level 

EXPLANATION 

~ Outcrop area of the 

Englishtown Formation 

-+75-

Piezometric-surface conlour lines 

lnlftrvol 2 5 feel 

Direction --of ground 

water movement 

Dot um is mean sea level 

ARTICLE 51 

N 

t 

10 15 20 25 Ml LES 

A 

N 

t 

10 15 20 25 MILES 

c 

EXPLANATION 

~ Outcrop area of the 

Englishtown Formation 

~- -400---

Structure contour 

Interval 400 feel 

--25--

lsopach 

lnlftrval 2 5 feel 

Datum is mean sea level 

EXPLANATION 

Outcrop area of the 

Englishtown Formation 

~ Ca+Mg >90 percent 

[]] 

Ca+Mg >50 percent 

~ Na+ K >50 percent 

~ Na+K >90 percent 

B-125 

N 

t 

10 15 20 25 Ml LES 

B 

N 

t 

10 15 20 25 MILES 

D 

FIGUI~E 51.1.-Maps showing the relation between topography, geology, ground-wa.ter movemEc'nt, and cation hydrochemicnl facies in the lDnglishtown Formation. A., Gen~ralized topography of the cC'astal plain of New Jersey. B, Structure cont~urs of the top of the Englishtown Formation and isopachs of the sandy part· of the formation. 0, Generalized 

ground-water 1novement in the sandy part of the formation in December 1958. D, Hydrochemical facies showing 

relative proportions of cations in the ground water of the sandy part of the formation. 
B-126 GEOLOGICAL SURVEY RESEARCH 19 6 2 

morillonitic clay in the subsurface, which in turn substantiates the supposed marine origin of the Englishtown Formation in that area. 

The zone separating the cation facies containing 

more than 50 percent Ca + Mg from that containing 

more.than 50 percent Na+ K is considered to be an "ionexchange front." This front is presumably moving 

slowly east-southeastward at an: indefinite rate in the 

direction of the movement of the water within the 

formation. The present alinement and position of the 

front is governed more by the piezometric surface that 

existed prior to pumping from the Englishtown Formation than by the present piezometric surface. 

REFERENCES 

Back, 'Villiam, 1960, Origin of hydrochemical facies of groundwater in the Atlantic Coastal Plain : Internat. Geol. Cong., 

21st, Copenhagen, 1960, Proc., pt. 1, p. 87-95. 

--1961, Techniques for mapping hydrochemical facies ; Art. 

423 in U.S. Geol. Survey Prof. Paper 424-D, p. D380-D382. 

Groot, J. J., and Glass, H. D., 1960, Some aspects of the mineralogy of the Atlantic Coastal Plain, in Clay Conf., 7th, 

\Vashington, D.C., 1958: New York, Pergamon Press, p. 

271-284. 

Minard, J. P., and Owens, J. P., 1960, Differential subsidence 

of the southern part of New Jersey coastal plain since early 

Late Cretaceous time: Art. 82 in U.S. Geol. Survey Prof. 

Paper 400--B, p. B184-B186. 

52. USE OF Na/Cl RATIOS TO DISTINGUISH OIL-FIELD FROM SALT-SPRING BRINES IN WESTERN OKLAHOMA 

By A. R. LEONARD and P. E. WARD, Oklahoma City, Okla. 

Work done in cooperation with the U.S. Public Health Service 

At several places in western Oklahoma and nearby 

Kansas and Texas highly mineralized ground water 

issues from natural salt springs. The chloride content 

of water from individual springs is as much as 190,000 

ppm (parts per million) and in nearby streams at times 

reaches several thousand parts per million. Some brine 

pumped from oil wells in the area also may find its way 

into surface streams. The oil-field brines have concentrations of chloride and dissolved solids in the same 

ranges as the natural brines. Neither chloride nor dissolved solids content can be used to distinguish brine 

from the two sources nor to identify the source of mineralized water at many places in surface streams in 

concentrations of only a few thousand parts per million. 

During a recent study, it was found that the ·two 

types of brines could be distinguished on the basis of 

their N a/Cl ratios. The procedure was suggested to the 

junior author by chemists of the Quality of Water 

Branch, U.S. Geological Survey. On figure 52.1 the 

ratio.of sodium to chloride (both in parts per million) 

has been plotted against the concentration of chloride 

for selecwd: oil-field and salt-spring brines. Brines 

from several natural salt springs are remarkably similar in chemical quality, although they range in chloride concentration from a few thousand to nearly 

200,000 ppm. The Na/Cl ratio for these waters is uniformly within 1 or 2 percent of 64/100. This suggests 

a nearly pure halite source for the sodium and chloride 

because the combining ratio of sodium and chloride in 

parts per million is 65/100, and halite is virtually pure 

sodium chloride. 

In the same area, oil-field brines consistently have 

N a/Cl ratios of less than 6Q/100, but the ratio decreases 

as the chloride content increases (fig. 52.1). The average ratio for about 30 oil-field brines plotted was 

about 50/100. In the oil-field brines the excess of 

chloride over sodium evidently results from other compounds of chloride, for example, calcium or magnesium 

chloride, which are not present in either the halite deposits or the water from the natural salt springs. 

. On figure 52.1 analyses of water from several rivers 

in ·Oklahoma have been plotted tO demonstrate use of 

the ratio for identifying the source of chloride in the water. Analyses are from published reports of the Geological Survey (Dover, 1959; Pate and others, 1961). 

Analyses 1 to 4 are of water samples collected from the. 

Little River, near Sasakwa, Seminole County, Okla. 

Samples were collected during 1956 when the flow was 

low and the miner~l content was high. The N a/Cl 

· ratio ranged from about 47/100 to 50/10~, indicating 
~-

-\ 

ARTICLE 53 B-127 

200,000 

~I 

~:~ 180,000 

I 

I 

I 

160,000 

140,000 

z 

0 

\ I I~ 

\ (' 

~ \ I IO I \ 

0 I 0 

0 \ 0 I 

0 o\ 0 I 0 0 \ I 

:::i 

-l 

~ 120,000 

\ I 0 I 

I 

a: 

!'-' 

ll. 

(/) 

1- 100,000 a: 

c( 

\ ~I ~ I 0 

0 \ I 

+--o I 0 l 0 \ ll. \ I 

~ 

LJ 80,000 c 

a: 

0 

-l 

J: 

u 60,000 

\ ~ I 

\ ~: 

x4 . I I 0 I 

0 \ 0 I 

\ I 

\ I 

\ 0 I 0 \ 0 \ I 

40,000 0 \ I 

ox \ I 

3 \ I 0 

\ ~ 

20,000 

I ~ 

ci I 

x2 \ 8 ~I ~ 

I \ 6,b 1 \ 

x7 \ x8 x51 

40/100 50/100 60/100 70/100 

Na/CI 

l!.,munE 52.1.-Comparison of Na/Cl ratios for oil-field and natural-spring brines in western Oklahoma and southwestern 

Kunsus. Analyses of oil-field brines (Wright, 1957) are 

represented by circles, natural-spring waters by triangles, 

and analyses of river water by X 's. Superscripts are explained in text. 

that· the source of chloride in the water was oil-field 

brine. Large quantities of brine are discharged into 

this stream as it passes through oil fields a short distance. upstream from the sampling station. 

Analyses 5 and 6 are of water collected from the 

Cimarron River at the Perkins sampling station in 

Payne County, Okla., in December 1955 and February 

1956, respectively. Both samples represent low flow 

having a high mineral content. The N a/Cl ratios are 

higher than 60/100 because the source of most of the 

chloride is natural brine emerging from salt springs and 

salt plains upstream. 

Analyses 7 and 8 are of water samples collected from 

the Arkansas River near Tulsa, Okla., in October 1955 

and September 1956. They were collected at low flow 

when the mineral content was high for this station. 

The chloride in the water is from both oil-field and 

natural sources; accordingly the analyses plot between 

numbers 1 and 5 on figure.52.1. 

The N a,/Cl ratio is a useful tool for identifying 

the source of chloride in stream waters in the western 

Oklahoma area. If the ratio is greater than 60/100, the. 

chloride is most likely derived from natural halite 

deposits through water emerging from salt springs. If 

the ratio is near or less than 50/100, the chloride source 

is most likely connate water pumped from oil wells. 

REFERENCES 

Dover, T. B., 1959, Chemical character of surface waters of 

Oklahoma 1955-56: Oklahoma ·water Resources Board Bull. 

16, 144 p. 

Pate, C. 0., Murphy, J. J., and Orth, R. P., 1961, Chemical 

character of the surface waters of Oklahoma, 1956-57: 

Oklahoma Water Resources Board Bull.l8, 140 p. 

Wright, Jack, and others, 1957, Analyses of brines from oilproductive formations in Oklahoma: U.S. Bur. Mines Rept. 

Inv. 5326, 71 p. 

53. RELATION BETWEEN ALUMINUM CONTENT AND pH OF WATER, BEAVER CREEK STRIP-MINING 

AREA, KENTUCKY 

By GEORGE W. WHETSTONE and JoHN J. MussER, Columbus, Ohio 

Prepa;rea in cooperation with the Kentucky Geological Survey 

Water-quality studies in the Beaver Creek basin, 

Ketitucky, indicate that acid mine water is especially 

significant in transporting aluminum in solution. 

Aluminum is one of the most abundant metallic 

elements in the earth's crust, occurring principally as 

a silicate in clays and feldspars and as the commercial 
B-128 GEOLOGICAL SURVEY RESEARCH 1962 

ore bauxite, an impure hydrate oxide. The element is 

amphoteric in behavior and can be in solution either 

as a cation or as a part of a complex anion, as illustrated in the following equation: 

Al+3 +30H-1=;{ AJ~~W,a }AlQ2- 1 + H+1 + H 20 

Aluminum hydroxide is only slightly dissociated and is 

nearly insoluble in natural water, for which the pH 

generally ranges from 5.5 to slightly more than 8. 

The aluminum concentrations of natural water usually 

are less than 1 or 2 ppm (parts per million) and much 

of this probably is colloidal and undissociated. Dissociated aluminum as Al+3 occurs in amount.'l of more 

than 2 or 3 ppm only in solutions in which the pH is 

less than about 4. Aluminate ions (Al02- 1 ) are rarely 

found in natural water because, theoretically, they can 

be in solution in measurable amounts only at pH values 

of more than 9. 

Nat ural surface water in the Beaver Creek basin is 

poorly buffered. A marked reduction in the pH of 

the· water is caused by small amounts of sulfuric acid 

derived from the oxidation of pyrite and from hydrolysis involving sulfate, in the spoil banks of strip mines. 

Median values of pH and the range of aluminum 

concentrations are shown in the table below for two 

nonpolluted streams in the Beaver Creek basin-Helton 

Branch and West Fork Cane Branch-and for Cane 

Branch, which was polluted by acid mine waters. 

In the Beaver Creek basin, surface water free of acid 

mine water generally has a pH ranging from 5.0 to 7.3 

and an aluminum concentration of 0.4 ppm or less. 

Water in Cane Branch from January to June 1956, 

before the spoil bank was leveled, had a pH ranging 

Median values of pH and r,ange of aluminum concentration in 

surface water in Beaver Creek Basin, Kentucky, January 1956 

to September 1958 

pH Aluminum 

(in parts per million) Stream --

Median Maxi- Median Mini- mum mum 

------ West Fork Cane Branch _________ 6. 0 0. 2 0. 1 0. 0 Helton Branch __________________ 6. 7 .4 . 1 .0 Cane Branch ___________________ 3. 2 85 5. 5 .0 

90 

0 

80 

z 70 

Oz 

~0 

.:t::; 

O::..J 60 ...... - z~ 

w Ua:: 50 

zw Oa.. :. 

u 

C/) 40 ~ ...... :::::>0::: 

~ 

~~ 30 

0 

:::::>Z 

..J-

<t 20 

10 

0 

2.0 2.5 

0 

!a 

~ 0 

~ -~ ) 0 0 

0 ~0 

'"'o to 1n c 

3.0 3.5 4.0 4.5 5.0 5.5 

pH 

FIGURE 53.1-Solubility of aluminum as a function of pH in 

Cane Branch, 1956-58. 

from 4.0 to 6.8 and an aluminum concentration less 

than 5.0 ppm. 

From June 1956 to September 1958, the pH of Cane 

Branch water generally was less than 4.15, and the 

aluminum concentration was greater than 5.0 ppm (fig. 

53.1). The maximum aluminum concentration was 

85 ppm. Aluminum concentrations were highest for 

pH values less than 3.0. 

Aluminum concentrations in the ground water in 

the Beaver Creek area followed a pattern similar to 

that of the surface water. Water from coal test holes 

and springs had pH values greater than 5.0 and contained less than 0.2 ppm of aluminum. Water within 

the spoil bank frequently had pH values less than 2.8 

and had as much as 46 ppm of aluminum. Water 

from pools on the spoil bank had a pH less than 3 and 

an aluminum concentration up to 50 ppm. 

·~ 
,~ 

ARTICLE 54 B-129 

54. CHEMICAL QUALITY OF SURFACE WATERS .IN THE BRAZO.S RIVER BASIN, TEXAS 

By BuRDGE IRELAN and H. B. MENDIETA, Austin, Tex. 

Prepm·c(t in, C007Jet'ati01'~> with the B·razos R-iver A.1tthority arul the Tamas Water· Comrnissi01'~> 

The Brazos River basin (fig. 54.1) occupies 15 percent of the land area of Texas and extends from the 

I-Iigh Plains, where altitudes reach a maximum of 

4,200 feet and precipitation ranges fr01n 15 to 20 inches 

n. year, to the Gulf coast, where the annual precipitat·ion ranges from 45 to 50 inches. The average annual 

water discha.rge of the Brazos River at Richmoi1d is 

5,288,000 acre-feet for 39 years of record and represent:.s the discharge of about 99 percent of the Brazos 

River basin. 

T'he Brazos River ha.s not been as greatly developed 

for municipal and industrial use as the Trinity River 

.--. 

I 

0 200 MILES L---.J 

to the north and the Colorado River to the south. 

Major upstream reservoirs on both the Trinity and 

Colorado Rivers store water of good quality. In contrast, the large reservoirs on the upper Brazos River 

were designed primarily for power production and 

flood control, and they store water that is too saline 

for municipal and most industrial uses. IIowever, reservoirs on a number of upstrmun tributaries provide 

water that is suitable for municipal use. 

A study of quality-of-water data for the Brazos 

River basin shows that salinity was a problem as early 

as 1906 (Clarke, 1924, p. 126). The quality of the 

0 

I 

50 

I 

N 

100 MILES I 

1!""munE fi4.1.-Map of the Brazos River basin showing principal tributaries and hydrologic features. 
B-130 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

surface waters of most of the tributaries of the Brazos 

River ranges from excellent to good, in the general 

range from 250 to 500 ppm (parts per million) of dissolved solids, but most of the water in the main stem 

and two of its principal tributaries, the Salt Fork and 

the Double Mountain Fork Brazos Rivers, is saline 

(more than 1,000 ppm of dissolved solids) (Winslow 

and Kister, 1956, p. 45, 93-94). 

The s·alt load of the Brazos River is derived from 

basin-wide. solution of the products of rock weathering 

and decomposition, undetermined but apparently 

large amounts of oil-field brines, and natural brines 

and seeps. The flow from springs and seeps, although 

relatively small, contributes large quantities of salts to 

the stream system, for saturated brines have as much 

as 300,000 ppm of dissolved solids. About 50 percent 

of the annual salt load of the Brazos River is caused 

by inflow of brines from springs and seeps in the area 

above Possum l{ingdom Dam, wl1ich forms about 52 

percent. of the total drainage are.a of the basin but contributes only about 17 percent of the water discharge. 

Water of the Salt Fork Brazos River is too saline 

for most uses. Much of the runoff of the Salt Fork is 

from areas underlain by rocks of Permian age. The 

surface runoff from these areas contains large amounts 

of dissolved solids, and even larger amounts are contributed by the salt springs that rise in the barren 

salt flats of the drainage basins of Croton and Salt 

Croton Creeks. The average load of chloride in the 

base flow from the springs in the Salt Croton Creek 

basin was computed to be about 400 tons per day, 

about 40 percent of the average daily chloride load of 

the Brazos River at Possum Kingdom Dam. 

The water of the Double Mountain Fork is less saline 

than that of the Salt Fork and probably could be used 

as an irrigation supply but not as a municipal or industrial supply. The· quality of water of the Clear Fork 

Brazos River generally is good but would be better 

if brine pollution from oil fields were prevented. Records for the Lampasas, the Leon, and the Navasota 

Rivers indicate that the water of these streams is of 

excellent quality, but more data are needed to determine the variations in chemical quality. The quality 

of the water in other tributaries in the lower basin is 

inferred to be good from the results of miscellaneous 

sampling and form the types of rocks that underlie 

the basins. 

The difference in density of inflow into Possum 

Kingdom and "\Vhitney Reservoirs tends to cause density stratification. Samples collected in 1956 at Whitney Reservoir show that the chloride concentration at 

the bottom of the reservoir was about twice that at the 

surface. In June 1957 the dissolved-solids content of 

the wa'ter at the bottom of Possum J{ingdom .Reservoir 

was almost double that of the water released through 

the spillway. The water on the bottom remained saline even though the flood discharge during the previous month was more than twice the reservoir capacity. 

"\Vater passing the sampling station on the Brazos 

River at Richmond is a constantly changing mixture of 

water from the entire basin. In some years, releases 

from Possum Kingdom and Whitney Reservoirs are a 

large part of the flow at Richmond. In other years, 

more than half the flow enters the river downstream 

from' Whitney. The different sources of flow result in a 

marked variability of annual weighted-average and 

mean daily dissolved-solids loads. Although the mean 

daily loads generally are greater in years of high flow 

than in years of low flow, the relation between salt-load 

discharge is irregular because of the release of saline 

water from Possum Kingdom and Whitney Reservoirs. 

A comparison of the concentrations in the Brazos River 

at Richmond and at Whitney Reservoir indicates that 

inflow below Whitney Reservoir dilutes the water of 

the Brazos River. 

For 12 of the 14 years of record, the weighted-average 

dissolved-solids content of the Brazos River at Richmond was less than the recommended maximum ( 500 

pp~) of the U.S. Public Health Service (1961), and 

was never more than 1,000 ppm. 

If pollution from oil fields is controlled, the water of 

the major tributaries of the Brazos River, except the 

Double Mountain Fork and the Salt Fork, may be used 

by municipalities and industries. "\Vater of the Double 

Mountain Fork may be used for irrigation, but the 

water of the Salt Fork cannot be used for any purpose, 

except perhaps for oil-field injection, until the brine 

discharge from springs and seeps is prevented from entering the stream. Injection of water from salt springs 

into deep rock strata or impoundment and evaporation 

are possible remedial measures. 

The quality of water during low flows in the lower 

main stem can be improved even if the saline contributions from upstream continue. Increased conservation storage in the lower basin would permit the 

retention of the better quality waters for dilution of the 

saline water from the upper reaches. 

REFERENCES 

Ambursen Engineering Corp., 1956, Combined report on investigations directed toward the improvement of the Brazos 

River water: Brazos River Authority. 

Clarke, F. "\V., 1924, T,he composition of the river and lake 

waters of the United States: U.S. Geol. Survey Prof. Paper 

135, 199 p. 

I, 
'Ol.. 

ARTICLE 55 · B-131 

U.S. Public Health Service, 1961, Report on the Advisory Committee on revisions of U.S. Public Health Service 1946 

Drinking Water Standards: Am. Water Works Assoc. 

Jour., v. 53, no. 8, p. 935-945. 

Winslow, A. G., and Kister, L. R., 1956, Saline-water resources 

of Texas: U.S. Geol. Survey 'Vater-Supply Paper 1365, 

105 v. 

55. CHEMICAL QUALITY OF GROUND WATER IN ST. THOMAS, VIRGIN ISLANDS 

By I. G. GROSSMAN, San Juan, Puerto Rico 

Work done ·in cooperation with the Government of the Virgin Islands 

The Virgin Islands of the United States consist of 

about 80 small :islands approximately 50 1niles east of 

Puerto Rico and about 1,000 miles southeast cf Florida 

(fig. 55.1). St. Thomas, the second largest of the 

islands, is only about 1 to 3 miles wide ·and 13 miles 

long. Because of its excellent harbor, St. Thomas early 

assumed militnry and conunercial imporUt.nce, becoming 

the most populous island and the site of the capital, 

Charlotte Amalie, but its full potentialities have never 

been realized becn.use of a chronic water shortage. 

The island is very hilly a,nd has a centra.J ridge that 

parallels its long axis and rises to a maxin1um altitude 

of 1,556 feet. The hills are IIOCky and the colluvial and 

other unconsolidated materials are generally thin. A 

small but significant deposit of alluvimn extends along 

Turpentine Run, the only stream having a perennial 

reach, in the eastern part of the island. The annual 

· precipitation is cmnparatively high, averaging about 

4.6 inches, but the tropical ocen.nic climate, with a mean 

annual te1nperature of about 80°F, and the small range 

in 1nen.n n1onthly temperature permit a year-round 

growing season which, coupled with the steady blowing 

of the northeasterly trade winds, results in high evapotranspiration losses. 1\{oreover, the steep, rocky slopes 

faci1itu.te rapid runoff at the expense of ground-water 

recharge. 

The traditional source of potable water has been rain 

caught on "catchments," consisting of paved hillsides 

leading to storage tanks. Supplemental wn.ter supplies 

that are m.ore highly minern.lized are obtained fron1 

shn.llow dug weUs and from a very few springs. Charlotte An1alie employs a dun.l water supply, as snit water 

is used for .firefighting and flushing of streets. In 

recent years, the spiraling demand for water spn.rked 

by the :influx of tourists and new residents resulted in 

u. critical situation that was met only by shipping in 

additional wn.ter by barge from Puerto Rico n.t a rate 

that exceeded 1 million gallons per week in 1960. A 

distillation unit to convert sea water to fresh water, 

having a capacity of 250,000 gallons per day, was under 

construction in 1961. 

Complete chemical analyses of water from 31 wells, 

including 20 sampled in n.n earlier study (Vaughan and 

J(idwell, 1920) and 11 sampled recently (Grossman, 

1959), permit a delineation of the chemical quality of 

ground water from the shallow deposits. The ·wells 

were dt~g to depths ranging from 9 to 50 feet and averaging a,bout 18 feet. The only drilled well on St. 

Thomas is situated northeast of the hospital in the 

northern pa.rt of Chn.rlotte Amalie. It is 216 feet deep, 

but all of its very small supply was reportedly obtained 

N 

ico 1 

rf>; 

0 

.•c;s 

S E A ·'' ~ ~ (\,, ~ 

FIGURE 55.1.-Map of St. Thomas, V.I., and its geographic 

setting. 
B-132 GEOLOGICAL SURVEY RESEARCH ·1 9 6 2 

100 

0 

100 

o"' I 'J.(j 

O"' 

~(j 

0 

. EXPLANATION 

Well near • Magens Bay 

91 percent of analyses 

plot in shaded area 

FIGURE 55.2.-Chemical classification of water from shallow 

wells in St. Thomas, in percent of total equivale;nts per 

miliion. 

at a depth of 30 feet from clayey "detritus". overlying 

the bedrock. Hence its chemical quality is more likely 

to reflect that of water from the unconsolidated deposits 

than from the bedrock. This well was completely 

covered over when revisited in 1958. 

Ground water from the unconsolidated deposits commonly had a high mineral content; the average dissolved-solids content in 33 samples was 1,6Q,O ppm 

(parts per million). The lowest dissolved-solids con-· 

tent was 838 ppm;· only 3 samples of the 33. contained 

less than 1,000 ppm of dissolved solids. Two of the 

wells sampled by Vaughan were resampled in 1958. 

After a lapse of about 40 years, the dissolved-solids 

content in one remained about the same but that in the 

second had declined from 1,320 to 989 ppm. 

The proportions of the dissolved constituents in local 

ground water are influenced significantly by the geology, the degree of mixing with salt water, and the 

lingering urban pollution. The isla1~d is made up 

largely of volcanic rocks of probable Cretaceous ao-e . b ' 

although there ar~ some relatively thin beds of limestone in the northeast. The overall poverty of potash 

in all the bedrock is striking (D01melly, 1959). The 

potassium content of local water likewise was low; the 

average in water from 10 wells for which .separate determinations are available was only 6.5 ppm, with a 

range of from 4.0 to 10 ppm. By contrast; the sodium 

content in these 10 samples averaged 409 ppm and 

1:anged from 275 to 915 pp1n. Although some of this 

high sodium content reflected the relatively high sodium content of the volcanic bedrock from which most 

of the colluvial and alluvial cover is derived, some of it 

probably resulted from mixing with airborne salt and 

with sea water in shoreline areas. 

The maximum sodium· concentration recorded in the 

study was that in brackish water in a well on the north 

coast about 2,000 feet southeast of Magens Bay at an 

altitude of about 15 feet (fig. 55.1). W n.ter from this 

well had a dissolved -solids content of 5,800 ppm and a 

chloride concentration of 2,500 ppm (fig. 55.2). The 

chloride content of the 32 other samples ranged from 

118 to 979 ppm and averaged 400 ppm. Some wells produced salty or brackish water as a result of salt-water 

intrusion induced by overpumping. In and near Charlotte Amalie, ground water had been contaminated 

locally by salt water that had leaked from fire mains 

and· hydrants. Field tests made in 1945 on water from 

16 publicly owned wells in Charlotte Amalie showed an 

average chloride content of about 1,100 ppm (McGuinness, 1946, p. 24-26). 

As indicated on the geochemical graph (fig. 55.2) 

sodium is the predominant cation in the ground water. 

In some water, chloride is the predominant anion, and 

in other, bicarbonate or nitrate predominates. 

In Charlotte Amalie, chloride was not the only objectionable anion. The nitrate content in 16 publicly 

owned wells sampled in 1919 averaged 217 ppm and 

ranged from 9.5 to 419 ppm. By contra·st, the nitrate 

content of 3 rural wells sampled at the same time averaged only 14 ppm. Ten rural wells sampled in 1958 

showed an average nitrate concentration of only 11 

ppm, with a range of 0 to 44 ppm. Moreover, 8 of the 

10 samples contained less than 5.0 ppm of nitrate. Sanitary facilities were primitive in 1919, the year in which 

appropriations for sanitary sewers were first passed, 

and the high nitrate content of water from the public 

wells was attributed to human pollution (Vaughan and 

Kidwell, 1920, p. 25). As late as 1943, 247 open-pit 

i' 

,_-
.ARTICLE 56 B-133 

privies were still being used, most of them in Charlotte 

Amalie. l\1ost of the wells in the city had been sealed 

or were not in use when revisited in 1957. 

Although i1nproved sanitation 1night result in improvement of the quality'of water fron1 wells in the city, 

the possibility o of substantial additional ·recharge is 

limited by the small size of the tributary drainage basin 

and the widespread use of rn,infall frmn roofs and other 

catchments. :The most promising source of ground 

water of acceptable chemical quality appears to be in 

Turpentine Run basin, where 1 well of 9 yielded water 

containing less than 1,000 ppm of dissolved solids. Of 

the .remaining 8, 6 had water containing less than 1,300 

pp1n. Water from these six wells could be mixed with 

rainwater or other relatively fresh water for use without additional treatment, but the preference of Virgin 

Islanders for the relatively pure rainwater they are 

accustomed to might necessitate additional treatment. 

REFERENCES 

Donnelly, T. ·w., 1959, The geology of St. Thomas and St. John, 

V. I. : Caribbean Geol. Conf., 2d, Puerto Rico, 1959, Trans., 

p. 153. [1960] 

Grossman, I. G., 1959, Ground-water data from St. Thomas, 

V.I. : U.S.· Geol. Survey open-file report, 35 p. 

McGuinness, C. L., 1946, Ground-water reconnaissance of St. 

John, Virgin Islands, with a supplement on St. Thomas: 

U.S. Geol. Survey open-file report, 27 p. 

Vaughan, T. W., and Kidwell, C. H., 1920, 'rhe ground-water 

resources of the West Indian Islands, St. John, St. Thomas, 

Culebra, Vieques, and the eastern end of Puerto Rico: U.S. 

Geol. Survey open-file report, 53 p. 

·~ 

TOPOGRAPHIC STUDIES 

PHOTOGRAMMETRY 

56. A TEST OF THE DIRECT GEODETIC RESTRAINT METHOD OF ANALYTICAL AEROTRIANGULATION 

By RoBERT C. ELLER and MoRRis L. MoKENZIE, Washington, D.C. 

The direct geodetic restraint method of analytical 

aerotriangulation was first presented by Dodge in 1957 1 

and, after revisions in the geometrical approach, by 

Dodge, I-Iandwerker, and Eller. 2 Briefly, it is a simultaneous block solution for horizontal and vertical positions based on a method developed by Herget ( 1956). 

Input data for the method consist of ( 1) photographic 

coordinates for ground control and model pass points, 

(2) geographic coordinates and elevations for ground 

control, and ( 3) estimates of camera- position and orientation for each exposure station. The six parameters 

for each exposure station are improved through iterative solutions of linear equations involving adjustments 

by least squares. When stable conditions have been 

reached, geographic coot1

dinates and elevations for all 

points are computed. 

A prototype computer program for investigative use 

1 Dodge, H. F., 1957, Geometry of aerotriangulatlon: Cornell Univ., 

unpublished 1\:l.S. thesis. 

u Dodge. H .. F., Handwerker, D. S .. , and Eller, R. C., 1959, A geometrical foundation for ucrotrlnngnlatlon, Progress report 3, Analytical 

t\.et·ott·lnngulatlon research: U.S. Geological Survey, 'l'opographic Division. (duplicated) 

has been prepared with a problem-solving capability 

limited to nin~ photographs. Tests both with fictitious 

data by Dodge 3 and actual photographic and groundcontrol data demonstrate that the method has potential 

for producing ground-point positions to a degree of 

accuracy that satisfies standard mapping needs. 

A recent actual-data test involved nine aerial photographs of the Dale, Ind., quadrangle (fig. 56.1). The 

flight height for the photography was 9,000 feet above 

mean ground and the c.c'lmera's nominal focal length was 

6 inches. The horizontal control consisted of 5 firstand second-order triangulation stations and 1 transit. 

traverse station. All vertical control was established 

by standard U.S. Geological Survey supplemental control procedures. 

The photocoordinates of the ground control and 

model pass points were measured .on a Nistr·i TA-3 

stereocomparator by the U.S. Army Engineer Geodesy, 

s Dodge, H. F., 1958, Results of initial tests of analytical aerotriangulation in the Geological Survey, Progt·ess re)Jort 1, Analytical aerotriangulation research: U.S. Geological Survey, Topographic Division. 

(duplicated) 
B-134 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

N 

I ~·· I 

I® X 

. .. 

® 

X I 

I@ 

I 

I 

I ;r~~ 

II 

I 

6. x 

I 

1 ~~~ 

i~ 

~ I I I ® } 1: 1 .'L 

L __ ./ I l~-=---=-t--=-*"' 

I X 

- I 

I • 

I • 

X 

I 

I 

I 

I 

I 

I 

I 

I 

I 

.. • 

X 

I 

I 

I 

I 

I 

I 

I 

I 

I 

. . 

EXPLANATION 

@ Horizontal control points (3) 

® Vertical control points 

6. Horizontal check points 

X Vertical check points 

• Pass points 

Total number of points 

I :. 

I X 

I 

I 

I 

I 

I 

I 

I 

I 

. .. 

X X 

I 

I 

I • 

. I 

X I 

. . 

X 

X 

• (7) 

(3') 

(20) 

(63). 

(96) 

. .. 

• 

. 

@ 

® I 

I® 

I@ 

X X X I X 

I 

I X 

I . .. 

I X 

X I 

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L •• _._ 

I . L • -r-

. .. I • • L •_ L 

. .. L -I- --

FIGURE 56.1.-Analytical aerotriangulation test, Dale, Ind. 

Intelligence and Mapping Research and Development 

Agency. Three readings were made for each point and 

the average was accepted as the most probable value. 

Corrections for the systematic components of len-s and 

film distortion and film flatness were computed manually and applied to all photocoordinates before starting the computer solution. None of the horizontal 

ground-control stations could be identified on the photographs, but ground detail near each station was tied 

to the station by transit-stadia methods. By measuring 

the photocoordinates on this ground-detail imagery, it· 

was possible to compute the photocoordinates for the 

stations. 

In the preliminary computer runs, a minimum control 

distribution was used in order to eliminate· the influence 

of control on relative orientation and thus permit the 

detection and rejection of poorly transferred points. 

All control points except the minimum number used 

were treated as pass points. As a result of preliminary 

runs made first for individual strips and then for the 

combined strips, 3 pass points and 1 vertical control 

point were discarded. In addition, 4 pass points shown 

to be poorly transferred between strips were· rejected 

as tie points but retained for model control on 1 strip. 

To make the final run, it was not necessary to repeat 

the entire computer solution. Advantage 'vas taken of 

the partial solution provided by the two-strip preliminary run. Control in the pattern shown in figure 56.1 

was inserted and the computations were continued for 

two additional iterations. The final results are shown 

in the table below. It should be noted that the use of 

the term "root mean square error" in the table is not 

strictly valid in theory because of the small number of 

points considered; it is used here only to give an indi:-

. cation of the magnitude of the discrepancies. The 

vertical and horizontal errors are based both on the 

control points used in the solution and on the control 

points reserved as check points. 

Summary of results, analytical aerotriangulation test, Dale, Ind. 

Horizontal error ______________ -- ________ _ Vertical error ___________________________ _ 

Within-model parallax _________ -- ________ _ Model-to-model parallax _________________ _ Strip-to-strip parallax ___________________ _ 

Root mean Maximum 

square(feet) (feet) 

7. 93 

4. 53 

1. 54 

2. 66 

3. 37 

11. 83 

11. 90 

10. 96 

7. 16 

4. 26 

~-
,. 

~· 

ARTICLE 57, B-135. 

The photography ·used for this test was intended for 

the preparation of 1: 24,000-scale standard topographic 

quadrangle maps. The accuracy standards for such 

n1aps require that 90 percent of all discrete points tested 

fall w.ithin 40 feet of true horizontal position and that 

90 percent of all elevations tested be correct within onehalf a contour interval ( 5 feet in this case). The attainment of these sbwdard n,ccuracies in the finished 

n1ap requires that the photogrammetric control established by aerotriangulation be considerably more ac- · 

curate than the finished map. The horizontal accuracy 

of the network of points determined in the test is considered to meet this requirement, but vertical accuracy 

needs improvement. More accuracy should result from 

the use of polyester base or similar aerial film, targeted 

horizontal and vertical control, apd vertical control 

of greater accuracy. 

REFERENCE 

Herget, P. P., 1956, Computational extension of control along a 

photographed strip: Ohio State Univ. Research Found., 

Mapping and Charting Research Lab., Tech. Paper 201. 

57. RESEARCH ACTIVITY WITH THE U~O ORTHOPHOTOSCOPE 

By MARVIN B. ScHER, Washington, D.C. 

The function ·of an orthophotoscope is to convert conventional perspective photographs into uniform-scale 

photographs that portray all images in their correct 

orthographic positions. The value of a photograph 

upon which precise horizontnl-distn.nce men.surements 

can be made without applying corrections for image 

displacements due to tilt and relief has long been apprecin,ted. Such photogntphs simplify the problem 

faced by the geologist or engineer when he needs to 

record his scientific fi.eld observations in their correct 

orthographic positions. The ort.hophotmnosaic is an 

accurate assembly of orthophotographs which can be 

substituted for a planimetric ma.p. A mosaic of this 

sort often permits scientific field activity to. proceed 

without the delay otherwise imposed by inadequate map 

covern,ge :in an area of interest. 

An orthophotoscope may be describe!f as a photogrammetr.ic restituting enlarger that magnifies the different images on a perspective photograph inversely as 

their scale. Fabrication of the U-60 orthophotoscope, 

the third in a series of such instruments developed 

during the pn,st decade in the research laboratory of 

the Topographic Division, U.S.-. Geological Survey, was 

completed by the Property Mai~1tenance Shop in Silver 

Spring, Md., early in 1960. . · 

The design of the U-60 benefite.d fr01i1'the experience 

gained :in the development and use of the preceding 

orthophotoscopes. The structur~tl design has been altered to accommodate the st1pporting bar for ICelshtype projectors as well as the ellipsoidal-reflector type 

shown in figure 57.1. The flat film-supporting platform 

of the earlier instruments has been replaced with a 12-

inch-diameter cylinder around which the blue-sensitive 

film is attached. The cylinder and its concentric lighttight outer envelope are alined with their longitudinal 

axis horizontal and parallel to the w direction of the 

instrument. The platen carriage containing the scanning aperture is mounted ·on a track that extends the 

entire 32-inch length of the outer drum. The entire 

assembly of the drums, platen ca,rriage, and track can · 

be raised or lowered as a unit by manual control. The 

emulsion of the film is exposed through the scanning 

· aperture to small differential areas of the stereoscopicmodel surface as the platen carriage moves along its 

track. Although the film is exposed to both the red 

and· blue projected rays which create the anaglyphic 

model, only the blue rays have an actinic effect on the 

blue-sensitive film. 

The direction of travel of the platen carriage is reversed upon comi)letion of each successive scan. Two 

automatic, synchronized motions occur when the end 

of a scanning path is reached : The inner cylinder is 

rotated about its longitudinal axis and the assembly of 

the drums and platen carriage is translated in the y 

direction. The amount of cylinder rotation 1nust be 

precisely controlled to place the unexposed section of· 

film bordering upon the film area previously . exposed 

into correct position under the path of the scanning 

aperture. The assembly translation must be such that 

the scanned area across the stereoscopic model will be 

contiguous with that of the previous scan. This modification permits the operator to have an improved view 
B-136 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

FIGURE 57.1.-U-60 orthophotoscope. 

of the scanning platen, thereby enhancing the accuracy 

of scanning. Since the geometric faithfulness of 

orthophotographs depends directly upon scanning accuracy, a better product should result. 

The insertion of self -synchronizing mechanisms in 

the transmission of manual and automatic commands 

to the scanning assembly is another significant innovation of the 1960 instrument. A constant-speed electric 

motor rotates a generator selsyn that drives the scanning carriage in the x direction on the cylinder assembly. The z motion of the cylinder assembly is manually 

controlled through a handwheel mounted on the 

operator's chair. This handwheel rotates a generator 

selsyn that transmits the mechanical rotation of the 

handwheel electrically, through a flexible cable, to a 

motor selsyn mounted on the instrument. This selsyn 

in turn controls a lead-screw rotation that imparts z 

motion to the cylinder assembly. The response of the 

x and z motions to the commands issued through the 

servomechanisms is positive and smooth and represents 

a considerable improvement over that achieved by the 

mechanical-linkage transmissions used on the earlier 

instruments. Because each generator selsyn can function as a master for more than one motor selsyn, additional remotely located motors can be made to respond 

to the electric currents induced by the generator selsyn 

on the orthophotoscope. Means have thus been provided for reproducing and (or) recording the three 

coordinate motions of the scanning carriage by other 

remote instrumentation. 
·< 

ARTICLE 58 B-137 

Performance testing of the U-60 model began in 

~{arch 1960 n,t the Topographic Division's Branch of 

Uesearch and Design, in Arlington, Va. Tests designed to determine the geometric faithfulness of the 

produced orthonegatives led to further investigation 

:into: ( 1.) the geometric relationship between the rotation of the film-carrying drum and the translation .of 

the scanning carriage in the y direction, (2) the relationship between the width of the scanning aperture 

and the translation of the scanning carriage, (3) the 

parttllel ism of successive scanning paths, and ( 4) the 

perpendicularity of the z. motion of the scanning carriage to the plane def-ined by the. w and y axes of the 

.instrument.. Appropria,te adjustments were made to· 

.improve these features. 

Efforts to enhance the photographic quality of the 

ol.'thonegat.ives included the checking, adjusting, and 

(or) coi-rection of: ( 1) the shn.pe of the scanning ·aperture to reduce to insignificance, if not eliminate, scan 

lines; (2) excessive instrument vibration; and (3) light 

leaks that would cause unintentional exposure of the 

orthonegative. During these testing activities it was 

determined tlutt the original platen lacked the stability 

needed to insure a constant width of exposure for suc-

·cessive]y scanned stt·ips. 'Vhen a platen of sturdier 

design was machined and installed on the instrtlment, 

this difliculty was overcome. 

Studies were made to detern1ine the effect on image 

definition in the orthonegative caused by varying tl~e 

dimension of the scanning nperture parallel to the 

direction of scan. A reduction in this dimension has 

the effect of n, ~ho1ter exposure time for each segment 

of the orthonegative. vVhen this dimension had been 

reduced to a va.lue of 0.3 mm, it was noted that harmonics in the horizontal motion of the scanning carriage were registering photographically on the orthonegative. A value of 0.4 mm was then determined to 

be optimum for the present scanning speed of the 

instrument. 

Several minor features were added to the instrument 

to facilitate operational procedure. A scale was added 

to indicate the y setting of the scanning carriage. 

Safelights were installed in appropriate locations. 

Clamps were added to the x and y motions of the 

center projector of the three-projector group so that 

the center projector can be locked in position directly 

above thecenter of the area traversed by the scanning 

carriage. A mercury switch was installed on the carriage to illuminate automatically either the right-end 

or the left-end projector, depending on the position of 

the scanning carriage along the scanning track. This 

provision makes feasible the continuous scanning of two 

adjacent stereomodels in the x direction. 

. The first production assignment of the U-60 orthophotoscope involved the prepa1·ation of 1 :~0,000-scaJe 

orthophotomosaics of three standard 71f2-minute quadrangles in Idaho. Seventeen orthonegatives were required to cover the area; nine of these negatives were 

exposed with the U-60 and the remainder with an 

earlier orthophotoscope. Comparison of the products 

of the two instruments demonstrated the superior appearance of the orthophotographs prepared with the 

newer instrument. 

FIELD CONTROL 

58. RESEARCH ON TARGET DESIGN FOR PHOTOIDENTIFICATION OF CONTROL 

· By DAVID· LANDEN, Washington, D.C. 

A research project to improve the design o~ targets 

used for photo.identificat.ion was carried out by the U.S. 

Geological Survey in 1960 ~~nd 1961. A large tra~t of 

land in the Dulles International Airport property at 

ChantiBy, Va., was made available through the cooperation of the Federal A v.iation Agency for use as a testing range. Targets of various sizes, patterns, and materials were laid out, then standard vertical aerial photographs of the area were made. In addition, supplemental black-and-white and color photographs were 

taken with a short-focal-length 35-mm camera. The 

targets were evaluated by observation in a stereomodel 

to determine the best target configurations, minimum 

sizes, and most ·suitable m.a,terials. 
B-138 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

Two 1,000-foot base lines were laid out at right angles to each other, and the terminal points were marked 

with cloth panels. Six parallel north-south lines were 

laid out at 100-foot intervals; these are marked 1 to 6 

(fig. 58.1) and are referred to as columns in the following discussion. Nine parallel east-west lines were laid 

out at 100-foot intervals; they are marked A to I and 

are referred to as rows. Individual targets are identified by their row letter and column figure, as C-4, D-3, 

and so forth. 

In order to arrive at a formula for minimum target 

sizes, initial target sizes were first selected. If these 

proved to be incorrect, the ~orrect size could be easily 

obtained ·from the stereo model tests. The determination of the initial target sizes to be photographed at 

altitudes varying from 1,000 to 23,500- feet was based on 

the fact that an image measuring 0.02 inch can usually 

be recognized on mapping photography. (In the 

l{elsh plotter model such an image will measure a pproximately 0.1 inch.) The overall size of an object 

on the ground corresponding to 0.02 inch at 1 : 24,000 

scale is 40 feet. If single target panels are arranged in 

cross-shaped configuration and are spaced about 6 feet 

from the center, the panel length required would be 

about 12 feet. The initial reference panel was 3 feet 

wide because most cloth is available in this width. 

Other panel sizes were. computed. proportionately as 

simple fractions of the flight altitude H when length 

L=H/1,000 and width .W=L/4. . 

A characteristic and unique target pattern is needed 

to provide positive recognition against a complex background that may contain other patterns. Tests were 

made for comparison between 3-legged radial targets, 

which are most widely used, and 4-legged or crossshaped targets. The configuration of a square, circle, or rectangle was not selected because such a pattern 

does not always provide positive identification unless 

its location is known in advance. Right-angle or other 

two-legged targets also were eliminated because experience showed 'that the apex of such a target bleeds beyond its proper boundaries and introduces a significant 

error. 

Because such factors ~s a variable background affect 

the recognizability of a target, some targets having an 

uncontrasted center were compared with similar targets 

having the center paneled in black, which provides a 

sharp_ contrast. A black center also permits better centering of the floating mark in the stereomodel tests. · A 

record of seasonal variation of the background was obtained by photographing the targets 3 .times during a 

1-year period. The six columns of targets shown on 

figure 58.1 are described below. 

Column 1 consists of 9 open-centered 3-legged targets. The panel length is 1/1,000 of the flight height; 

the width is 1/4,000. The panels extend radially and 

are spaced from the center a distance equal to twice 

the width of the panel. Material is white cotton sheet-

. ing or muslin. Minimum panel sizes for ~the indicated 

flight heights are given in table 58.1. 

'Column 2 consists of 9 black-centered 3-legged targets the same size and configuration as those in column 

1 but with black cloth centers to provide increased 

contrast. 

Colunm 3 consists of· 9 black-centered 4-legged targets. The white panels are the same size as those in 

columns 1 and 2. The centers are black panels the 

same size as the white panels. · 

Column 4 was used to test a principle in vismtl optics 

that, for a given area, detectability is influenced to a 

large extent by the perimeter of an observed object. 

The column consists of 7 open-centered 3-legged targets 

having panels of white cotton sheeting. Each pariel is 

36 squa.re feet in area, but for each target the perimeter 

of the panels increases as the ratio of panel length to 

panel width increases, as follows : 

Panelsi.ze (feet) 

Target Width Length A-4 ____________________ 6 6 

B-4-----------~--------3 12 

C-4--------------------2.5 14 ])-4 ____________________ 2 18 

~--------------------1.5 24 F-4 ____________________ 1 86 

G-4 ____________________ . 5 72 

The shorter targets A -4 to C-4 are easier to see than 

the longer ones. The possible ad vantage of increased 

perimeter of the longer targets was reduced by weeds, 

g-rass, and shadows that masked the edges. 

Column 5 consists of 9 miscellaneous 4-legged targets 

made of material that included white freezer paper, 

white polyethylene film, black polyethylene film, aluminum foil, and fluorescent color materials that have 

special characteristics. 

Column 6 consists of panels used to appraise the durability of various typical, easily procured materials 

over a period of approximately 1 year. The panels 

are spaced 50 feet a.pa.rt. Each panel is 3 X 12 feet and 

is made ,of unbleached muslin in both 4.6- and 2-ounce 

weights, white cotton sheeting, white jean, white bunting (flagging), denim, butcher p:tper, rosin building 

paper, white paint (mi road), lime, both white and 

black polyethylene film, black tar paper, and· black 

muslin. · 

Seven targets were placed in the nearby wooded areas 

to study the relations between percentage of woods 

cover and detectibility, seasonal variations in detecta-
ARTICLE 58 B-139 

bility, and the use of large or intermittently spaced 

materials alternating between open and closed patches 

in overhead cover. 

Standard mapping photography was flown over the 

target area from flight heights of 1,000, 2,000, 5,000, 

8,500, 11,500, 14,000, 18,700, 20,000 and 23,500 feet. A 

Fairchild cartographic camera equipped with a 6-inch 

Planigon lens was used to obtain compilation-type 

photography. The targets were completed in July 1960 

and aerial photogr~phy was flown during three seasonal 

periods: (1) September 14 and October 7, 1960; (2) 

November 7 and December 2, 1960; and ( 3) March 26 

and April 14, 1961. During the third and final run, 

the trees were bare and the targets in the wooded areas 

could be readily identified. In the open testing range, 

however, the ground was light colored because of the 

relative absence of vegetation, and target detection was 

more difficult because of the reduced contrast. 

TABLE 58.1-_Minimum panel sizes for indicated flight heights 

Target 

A-1 _____________________ _ B-1 _____________________ _ C-1 _____________________ _ D-1 ____________________ _ E-1 _____________________ _ 

F-1 _____________________ _ 

G-1 ____________________ _ Il-l ____________________ _ I-1 _____________________ _ 

Panel size (feet) 

Flight height !-----:------- (feet) 

1, 000 

2, 000 

5, 000 

8, 500 

11, 500 

14,000 

18, 700 

20,000 

23, 500 

Length Width 

1. 0 

2. 0 

5. 0 

8. 5 

12.0 

14.0 

19. 0 

20.0 

23. 5 

0. 25 

. 50 

1. 25 

2. 0 

3. 0 

3. 5 

4. 5 

5. 0 

6. 0 

FIGURE 58.1.-U.S. Geological Survey target-testing range at 

Chantilly, Va. Flight height 1,000 feet. (White line at bottom of photograph is a panel, 40 inches wide and 108 feet 

long, that identifies the test range.) 

TABLE 58.2.-Results of stereomodel evaluation tests of targets photographed during March and April1961 from heights of 1,000 to 20,000 

teet (D, detectable; N, nonvisible; R, recognizable) 

~ / 3(}-32 18-20 36--37 11-12 9-10 7-8 5-6 3-4 Model / 

----- {t;)?::w Row ~ 1,000 2,000 5,000 8,500 11,500 14,000 18,700 20,000 

/ 

I RRR R RRR R RRR R RRR R RRR R RRR R RRR N RRR N I 

H RRR R RRR R RRR R RRR R RRR R RRR R RRR N RRR N H 

G RRRRR RRRRR RRRRR RRRNR RRRND RRRND RRRNN DDDNN G 

F RRRRR RRRRR RRRRR RRRNN RRRNN RRRNN DDDNN NNNNN F 

E RRRRR RRRRR RRRRN RRRDN RRRNN DDDNN NNNNN NNNNN E 

D RRRRR RRRRR RRRRR RRRRR NNDD:R' NNNNR NNNNR NNNND D 

c RRRRR RRRRR RRRRR NNNRN NNNRN NNNDN NNNNN NNNNN c 

B RRRRR DDDRR NNNRR NNNRN NNNRN NNNDN NNNNN NNNNN B 

A NNNRR NNNRR NNNRR NNNRR NNNRR NNNDN NNNNN NNNNN A 

~w/ 

~olumn 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 

~ c 

629660-,62--10 
B-140 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

A 35-mm hand-held camera was used for black -andwhite photography in the low-altitude 1,000- and 2,000-

foot flights. Using the 35-mm supplemental photographs, the most effective :target patterns, minimum 

sizes, and material were evaluated. The three flights 

also carried a separate 35-mm camera with 50-mm focal 

length equipped for color photography. The color 

photography was needed to appraise the fluorescent 

materials used and to compare the color photography 

with black-and-white photography .. 

By visual inspection of the aerial photographs and 

the stereomodel, a four-man evaluation group selected 

(a) the most effective pattern of the target; (b) minimum sizes of target panels for various flight altitudes; 

and (c) the most suitable material. 

When the appraisal of the stereomodel was not unanimous, the test was reexamined by the four observers 

without reference to previous tests. Final decisions on 

individual targets were unanimous. Targets evaluated 

in the stereoscopic model formed by ER-55 projectors 

were then classified as : 

Nonvisible (N) .-The target could not be determined even when its approximate location was 

known. 

Detectable (D) .-The target could be seen but its 

shape could not be recognized. 

·Recognizable (R) .-The configuration of the target could be positively identified. 

Table 58.2 is an example of such a steromodel test of 

the targets photographed during the third and final 

flight. 

Minimum recognition criteria obtained from stereomodel testing of 4-legged targets that were exposed 

during the 9-month period are shown in figure 58.2. 

The tests· indicate that the area of a target, or 

panel, should be proportional to the square of the 

flight height, and that 4-legged targets are more 

recognizable than 3-legged targets. Targets with legs 

separated radially from the centers are more recognizable than those which are not separated. Targets 

placed on low-contrast backgrounds can be made more 

recognizable by providing a black center. Four-legged 

targets having 3- X 12-foot panels should be adequate 

for standard compilation photography flown at heights 

up to 12,000 feet. At higher altitudes the panel sizes 

should be proportionally longer and wider. The minimum length and width for the higher altitudes should 

be equal to the flight height divided by 1,000 and 4,000 

respectively. The tests suggest that panel sizes of 3 X 

12, 4 X 16, 5 X 20, and 6 X 24 feet could have been 

used for the entire range of photographic heights up to 

24,000 feet. 

~ 

UJ 

z 

< 

Q.. 

u..i' 

01-

I<!' 

1-z 

(!'~ z 

UJIO 

-lC\o! 

UJ'TI -l 

mi 

<I- NO 

(!' z~ ....... 

01-

()[/J 

U.IUJ 

a::u.. 

~~ 

::J 

~ 

z 

~ 

26 

18 

16 

14 

12 

10 

6 

4 

2 

8000 12,000 16,000 20,000 24,000 

FLIGHT HEIGHT, IN FEET 

l!.,IGURE 58.2.-Recognizability of targets in relation to 

flight height. Only 1 flight at 23,500 feet. 

Targets for supplemental photography may be either 

3legged or 4legged. A wide-angle 35-mm-focal-length 

hand-held camera should provide adequate coverage at 

1,000- and 2,000-foot altitudes if enough nearby details 

are available for transferring the point. Transfer of 

points to the mapping photography should be made 

under a stereoscope. The usefulness of supplemental 

photography is greatly increased if it can be flown at an 

altitude which results in approximately the same scale 

as the compilation photography, but the height should 

not exceed 5,000 feet. 

White polyethylene film (target D-5), either 0.004 

or 0.006 inch thick, is recommended: the heavier material should be used where the target is liable to be 

damaged by wind and sun. Other white materials 

such as unbleached muslin ( 4.6 oz.), cotton sheeting 

( 4.6 oz.), and mercerized flagging material or bunting 

are satisfactory.. Black doth or black tar p~t.per may 

be used to provide contrast. 

. SELECTED REFERENCES 

Aschenbrenner, C. M., 1954, Problems of getting information in 

and out of air photographs: Photogramm. Eng., v. 20, no. 3, 

p. 398-401. 

Pryor, ,V, T., 1958, Photographic targets for markers of survey 

control: Highway Research Board Bull. 199, p. 49-67. 

Traenkle, C. A., 1954, Resection in space by .projective transformation: Photogramm. Eng., v. 20, no. 1, p. 157. 

Van Zandt, F. K., 1961, Sheep Mountain cadastral survey: The 

Militar~ Engineer, v. 53, no. 353, May-June, p. 194-197. 
ARTICLE 59 B-141 

59. NEW ELEVATION METER FOR TOPOGRAPHIC SURVEYS 

By JULius L. SPEERT, Washington, D.C. 

In April 1961 the Topographic Division of the Geo1ogical Survey acquired two new elevation meters for 

determining the elevations of supplemental control stations for stereotopographic mapping. The new, radically improved ·elevation meters were built by the 

Sperry-Sun Well Surveying Co., based on specifications 

developed jointly with engineers of the Topographic 

Division. 

Basically, the elevation meter is a vehicle-borne electromechanical device for measuring differences of elevation along a traversed route (fig. 59.1). It contains a 

very sensitive · electronic pendulum for continuously 

measuring the instantaneous slope of the road. Distance 

traveled is measured by a calibrated small fifth wheel 

near the pendulum. The product of slope distance 

times the sine of the inclination angle is integrated 

continuously by a built-in electronic computer to yield 

the desired elevation difference. To maintain the desired accuracy, precise calibration and adjustment are 

necessary for many of the mechanical and electronic 

features of the. equipment. 

The pendulum is supported on a bar between the front 

and rear axles, near the left wheels. To assure the 

measurement of true slope, uniform air pressure must 

be maintained in the tires on these wheels at all times. 

These tires are therefore connected to a common regulated-pressure manifold to maintain their pressure 

regardless of temperature, speed, or other variables. To 

a void changes in load distribution on the tires because 

of fuel consumption during operation, a special gasoline tank is provided as near as possible to the center of 

gravity of the vehicle. 

FIGURE 59.1.-Elevation meter, 1961 model. 
B-142 GEOLOGICAL SURVEY RESEARCH 1 9 6 2 

To a void false slope measurements on crowned roads 

and on curves, it is essential that the rear wheels traverse 

exactly the same path as the front wheels. This is 

accomplished by steering with all four wheels when 

the meter is in operation. The rear axle is therefore 

a duplicate of the front axle. Four-wheel drive is also 

available for use on soft roads. 

All the electronic circuits are transistorized and are 

printed ~n pluggable boards, to reduce power requirements and field maintenance problems and to improve 

reliability. In many cases, troubleshooting in the field 

consists merely of replacing circuit boards, in turn, 

until the faulty one is located. 

Precise adjustment of the pendulum is, of course, 

essential to accurate measurement of elevation. The 

p~ndulum base is first alined with the line connecting 

the axles. The pendulum itself is then calibrated on 

a special tilting stand for various slope angles between 

-15° and + 15°. After these mechanical adjustments, 

the meter is driven around a closed loop and a further 

electronic adjustment is made, if necessary, to bring the 

loop closure to zero. 

Precision of elevation determination is a direct function of precision of distance measurement. The fifth 

wheel is therefore calibrated periodically to compensate 

for wear, and its tire pressure is maintained constant 

by connection with the regulated-pressure tank. Effects 

of centrifugal force on the wheel circumference are 

compensated electronically. This compensation is calibrated both at very slow speeds and at higher, operating 

speeds. 

The danger of inaccurate recording is overcome in 

the new elevation meter. by an .automatic printing 

recorder. The vehicle is stopped for each elevation 

reading, to avoid dynamic effects on the pendulum, and 

the following information is automatically printed on 

adding-machine tape at the push of a button: The sta.-

tion designation (preset manually at each s~ation), the 

elevation of the starting point on the line (preset manually at the beginning of the run), the increment in 

elevation, the elevation of the new point, and the 

distance from the starting point. This distance is compared visually with that on a mechanical counter, as a 

check on the electronic measurement of distance and 

elevation. 

A small builders' level and a level rod are used to tie 

to bench marks and other off-road points. The level 

is supported on a sp~cial bracket so that the operator 

may take a rod reading on a side point without leaving 

his seat. 

The cab of the vehicle is air conditioned to assure 

dust-free operation of the delicate equipment. Numerous other features are included for comfort, convenience, and efficiency. A number of safety devices are 

included to reduce traffic hazards. The vehicle is 

equipped with a full set of replaceable spare parts, 

necessary handtools, calibration and test equipment, and 

other survey equipment that might be needed on an 

assignment. A special electrical-analog adjuster is 

included so that a least-squares adjustment may be applied to survey networks in the field if desired. 

In normal operations over good roads, the elevation 

meter may be driven at speeds up to 25 miles per hour. 

On soft or rough roads it is necessary to reduce the 

speed to protect the equipment, to maintain accuracy, 

and to avoid driver strain. Average survey mileage 

ranges from 30 to 50 miles per day, with a maximum of 

102 miles recorded in a single day over good roads. 

Adjusted elevations accurate within 1 or 2 feet are 

readily attainable with proper controls on planning and 

execution of the work. Lines may be double run for 

greater accuracy. The elevation meter is used most 

effectively on large projects with a fairly dense network of passable roads. It is not economical on small 

projects or where good roads are sparse. 

·r 
SUBJECT INDEX 

[Fol' major topic headings, such as "Econo~ic Geology," "Stratigraphy" , "Ground Water" , see un d er St a e t names or refer to "Table of Contents"] 

A 

ABS determinations, methylene blue 

method ------'------- Aerotriangulation, analytical, direct 

geodetic restraint 

method ------------- Alaska, eastern, stratigraphy ______ _ 

Alluvial fans, relation of morphology 

to drainage-basin characteristics -----------

Alluvium, movement of ground water 

in ------------ Alu!llinum, in surface water, relation to pH __________ _ 

Ammonites, Cretaceous, Colorado __ _ 

Cretaceous, Montana _________ _ 

South Dakota ___________ _ 

Jurassic, California __________ _ 

Triassic, California ___________ _ 

Antarctica, geochemistry, Taylor 

Glacier ------------~ 

Arizona, geomorphology, Colorado 

River system--~------

ground-water, Flagstaff ar~a __ _ 

Artesian water, rate of upward 

leakage -------------

B 

Basalt, index of refraction measurements ------------ Belt Series) Idaho, stratigraphy ___ _ 

Beryl, in veins in limestone _______ _ 

Boron; determination of, in water 

containing fluorine ___ _ 

Brines, oil-field; Na/Cl ratios ______ _ 

c 

California, geomorphology, San Joaquin Valley, l!..,resno 

County ------------- geomorphology, San Joaquin 

Valley, Los BanosKettleman City ·area __ 

geophysics, Coast Ranges, northern ----------------- Great Valley ____________ _ 

Klamath. Mountains ______ _ 

paleontology, Klamath Mountains, southern ______ _ 

Sierra Nevada, Kings River 

area ----------------

stratigraphy, Sierra Nevada, 

Kings River area _____ _ 

Sierra Nevada, American 

River area __________ _ 

surface water, Sacramento 

River, Sacramento ___ _ 

Carbon dioxide, in sea water and 

sediment ------------ Chloride, in ground water_ ________ _ 

in surface water ____________ _ 

Cinnabar, in fault zones _________ _ 

Clay, relation of content in sediments 

to volumetric shrinkage -----------------

Article 

49 

56 

11 

19 

37 

53 

22 

22 

22 

6 

23 

28 

18 

89 

40 

29 

5 

2 

48 

52 

19 

16 

25 

25 

25 

23 

7 

7 

6 

46 

33 

33 

52 

2 

16 

Article 

Clay balls, deposition and formation_ 14 

'colorado, geomorphology, Larimer 

County ------------- 17 

ground water, Las Animas_____ 44 

paleontology, Boulder County__ 22 

Otero County_____________ 22 

Pueblo County------------ 22 

stratigraphy, Larimer County__ 17 

Colorado Plateau, alluviation and 

erosion ------------·- 18 

Colorado Shale, Fall River Sandstone 

Member, Co I or ado, 

phosphate nodules____ 12 

Cretaceous, Black Hills, dip directions 

in crossbedding_______ 13 

Black Hills, new stratigraphic 

unit ---------------- 8 

Colorado, Haresiceras__________ 22 

Montana, faulting_____________ 3 

Haresiceras ------------- 22 

South Dakota, Haresiceras_____ 22 

Crystalline rocks, effect of weathering 

on water-yielding properties --------------- 43 

D 

Dakota Sandstone, Colorado, aquifer 

tests ---------------- 44 

Detergents, in water, ABS determinations --------------- 49 

Dewey Lake Redbeds, New Mexico 

and Texas, correlations 

and stratigraphic relations .--------------- 9 

Dianthrimide method, determination 

of boron_____________ 48 

E 

Elevation meter, fo.r topographic 

surveying -----------

Englishtown Formation, New Jersey, 

hydrochemical facies __ 

Entrada Sandstone, Colorado, aquifer 

tests ---------------- Eocene, New Jersey, marginal sea __ _ 

Evaporation, from salt-flat areas ___ _ 

Evaporites, prospecting for ________ _ 

F 

Faults and faulting, as ore controls __ 

detachment faults-------------

effect on movement of ground 

water --------------- relation to ground water_ ____ ""_ 

Fluorescence analysis, lanthanum oxIde as an absorber ___ _ 

Fluoride, determination of boron in 

presence of __________ _ 

Fluorite, in veins in limestone ____ _ 

Foraminifera, Eocene, New Jersey __ _ 

"400-foot sands," Louisiana, hydrochemical facies ______ _ 

59 

51 

44 

21 

40 

2 

1 

3 

4 

39 

31 

48 

2 

21 

50 

G 

Garnet, vanadium-rich 

Geochronology, radioca-rb~~-d-at;;=== 

Georgia, ground water, Georgia Nuclear Laboratory _____ _ 

surface water, Tired Creek, 

Cairo area __________ _ 

Yellow River, Snellville 

area ---------------- Glasses, determination of silica in __ 

. Gold, in veins in rhyolite ______ .:_ __ _ 

Granite, riebeckite, thorium and uran- ium content_ ________ _ 

Greenland, Centrum SJ'l, geophysics __ , 

H 

Haresiceras, recent discoveries, in 

Colorado and South 

Dakota ------------- Ha wail, engineering geology and 

geomorphology, Kilauea 

Volcano ------------- geophysics, Kilauea Volcano ___ _ 

petrography, Kilauea _________ _ 

Hydrochemical facies, relation to rock type ___________ _ 

Hydrothermal activity, along faults_ 

I 

Idaho, geochemistry, Madison Range, 

southern ------------ paleobotony, Madison Range, 

southern ------------

petrology and stratigraphy, Idaho 

batholith, Big Creek 

Article 

26 

11 

43 

47 

47 

30 

2 

27 

24 

22 

20 

20 

29 

50,51 

4 

10 

10 

area ---------------- 5 

stratigraphy, Madison Range, 

southern ------------ 10 

Index of refraction measurements, 

basalt -------------- 29 

Iron, in diorite___________________ 2 

Islands, aquifers on_______________ 55 

J 

Jurassic, California, unconformities__ 6 

California, metamorphic rocks__ 7 

K 

Kansas, southwestern, quality of 

water --------------- 52 

Kentucky, Beaver Creek area, quality 

of water_____________ 53 

L 

Lakota Formation, South Dakota and 

Wyoming, dip directions 

in crossbedding_______ 13 

Lanthanum oxide, as an absorber in 

fluorescence analysis___ 31 

Louisiana, quality of water, Baton 

Rouge area___________ 50 

B-143 
B-144 

Low flow, surface water, estimation 

of continuous defiArticle 

ciency -------------- 45 

M 

Magnetism, earth, in areas of ultramafic rock __________ _ 

Manganese ore, determination of thallium in _____________ _ 

Mapping, aerotriangulation ________ _ 

classification of stream channels 

on topographic maps __ _ 

elevation meter---------------

orthophotoscope -------------- target design for photoidentification of controL _____ _ 

Mesozoic, California, angular unconformity -------------

See also Triassic, Jurassic, Cretaceous. 

Metamorphism, of uranium-vanadium 

deposits ------------- of volcanic rocks ____________ _ 

Methylene blue method, ABS determinations -----------

Montana, geochemistry, Madison 

Range, southern _____ _ 

geochemistry, Bearpaw Mountains, Suction Creek __ _ 

paleobotony, Madison Range, 

southern ------------ paleontology, Carter County ___ _ 

sedimentary petrology and sedimentation, Bear p·a w 

Mountains, S u c t i o n 

Creek ________ : _____ _ 

stratigraphy, Black Hills uplift_ 

Madison Range, southern __ _ 

structural geology, Gallatin 

County, Tepee Creek 

quadrangle ----------

Morrison Formation, Colorado, aquifer tests ____________ _ 

N 

Nevada, economic geology, Humboldt 

Range -------------- economic geology, Taylor district, 

Ely ----------------- ground water, East Range,- Humboldt and Pershing 

Counties ------------

Humboldt River, Humboldt 

County -------------- structural geology, East Range, 

Humboldt and Pershing 

Counties ------------ Schell Creek Range _______ _ 

New Jersey, geochemistry, coastal 

plain, Monmouth and 

Ocean Counties ______ _ 

quality of water, coastal plain, 

Monmouth and Ocean 

Counties ------------

Mullica River, Wharton 

Tract --------------- paleontology and stratigraphy, 

coastal plain, Camden 

County -------------- New Mexico, ground water. Mortandad Canyon, Los 

Alamos area ________ _ 

mineralogy, Laguna mining district ----------------

sedimentary petrology, R i o 

Puerco area _________ _ 

stratigraphy, southeastern ____ _ 

25 

32 

56 

47 

59 

57 

58 

6 

26 

5 

49 

10 

12 

10 

22 

12 

8 

10 

3 

44 

2 

1 

4 

15 

4 

1 

51 

51 

36 

21 

37 

26 

14 

9 

SUB.JECT INDEX 

Article 

New York, ground water, Long Island, Champlin Creek__ 38 

Niobrara Formation, Colorado, Haresiceras -------------- 22 

North Pacific, C02 content of water 

and sediments________ 33 

0 

Ohio, ground water, Miami River, 

Dayton ------------- Oil-field brines, Na/Cl ratios ______ _ 

Oklahoma; western, quality of water_ 

Oligocene, Idaho and Montana, volcanic rocks __________ _ 

Ore controls, faults and faulting ___ _ 

stratigraphic ------------------

Orthophotoscopes, new developments_ 

p 

Packers, inflatable, use in water 

wells --------------- Paleobotany, Oligocene rocks, Mon- tana and Idaho ______ _ 

Paleozoic, California, angular unconformity -------------

See also Silurian, Permian. 

Pennsylvania, French Creek, surface 

water -------------- Perlite, prospecting for ___________ _ 

Permafrost, in stratified sand _____ _ 

Permian, Colorado, aquifer tests ___ _ 

New Mexico, southeastern _____ _ 

Texas; western ______________ _ 

Perennial flow, surface water, origin_ 

pH, of surface water, relation to 

aluminum content_ ___ _ 

Phosphate, nodules, origin ________ _ 

sedimentary, origin ___________ _ 

Photogrammetry. See Mapping. 

Pierce Canyon. Redbeds. See Dewey 

Lake Redbeds. 

Pierre Shale, Red Bird Silty Metmber, 

Black Hills uplift_ ___ _ 

Colorado and South Dakota, 

H aresiceras __________ _ 

Pleistocene, Arizona, Colol·ado River 

system ______________ _ 

Colorado, glacial tilL ________ _ 

Utah, Colorado River system __ _ 

Pollen, Idaho ·and Montana, Oligocene 

volcanic rocks _______ _ 

Pollution control, surface water ___ _ 

Porosity, estimating from specific 

gravity--------------

of saprolite-------------------

Prairie Divide Till, Colorado, correlation and extent_ _____ _ 

Precambrian, Idaho, metavolcanic 

rocks----------------

Prospecting. See specific mineral 

name. 

Purgatoire Formation, Cheyenne 

Sandstone Member, Colorado, aquifer tests __ _ 

Q 

Quaternary. See Pleistocene, Recent. 

R 

Radiocarbon dates, volcanic ash ___ _ 

Recent, Arizona, Colorado River sys-

·te'm ----------------- Utah, Colorado River system __ _ 

Reservoirs, effect on ground-water 

levels----------------

41,42 

52 

52 

10 

1 

1 

57 

44 

10 

6 

45 

2 

24 

44 

9 

9 

47 

53 

12 

12 

8 

22 

18 

17 

18 

10 

54 

15 

43 

17 

5 

44 

11 

18 

18 

35 

Rock analysis, by X-ray fluorescence_ 

Runoft', control by aquifer permea- .b111ty _______________ _ 

control by head differentiaL __ _ sources and variation ________ _ 

s 

Sailor Canyon Formation, California, 

Article 

31 

38 

38 

38,42 

unconformity at base-- 6 

Salt springs, Na/Cl ratios__________ 521 

Salt water, movement in coastal aquifers__________________ 34 

Salts, in ice platforms_____________ 28 

rate of accumulation by evaporation ----------------- 40 

Sand and gravel, locating deposits__ 2. 

Saprolite, hydrologic .properties_____ 43 

Scheelite, in veins in limestone_____ 2 

Sea level, effect on salt-water level in 

aquifers-------------- 34 

Sea water, C02 content____________ 33 

Sediment, deep-sea, C02 content____ 33 

Severinghaus electrode, determination 

of C02 content of water 

and sediments________ 33 

Shoo Fly Formation, California, unconformity at top_____ 6 

Silica, determination of, in tektites 

and glasses___________ 30 

Sillcate rocks, X-ray fluorescence 

analysis______________ 31 

Sillciflcation, as an ore control----- 1 

Silurian, California, angular unconformity -------------- 6 Silver, In rhyolite_________________ 2 

in silicified bodies_____________ 1 

in veins in limestone__________ 2 

"600-foot sands," Louisiana, hydrochemical facies_______ 50 

Sodium, in ground water__________ 52 

in S!Jrface water______________ 52 

South Dakota, paleontology, Meade 

County -------------- 22 

sedimentation, B 1 a c k Hills, 

northern_____________ 13 

stratigraphy, Black Hills upllfL 8 

Specific gravity, relation to porosity_ 15 

Specific yield, of saprolite'--------- 43 

Stibnite, in fault zones------------ 2 

Streamflow, analysis_______________ 45 

relation to movement of ground 

water________________ 36 

Strea•m profiles, ty·p~s------------- 42 

Subsidence, land, relation to clay 

content of sediments__ 16 

near-surface, alluvial-fan deposits__________________ 19 

Syenite, nepheline, thorium and uranium content_________ 27 

T 

Tektites, determination of silica in__ 30 

Temperature, ground ______________ 16, 24 

ground water _________________ 41, 42 

Temperature-depth relations, ground 

water________________ 42 

Tertiary. See Eocene, Oligocene. 

Texas, geochemistry, Big Bend National Park-----------

geochemistry, western ________ _ 

quality of water, Brazos River 

basin----------------

quality of water, western ______ _ 

stratigraphy, western _________ _ 

Thatlium, determination by X-ray fiuorescene ___________ _ 

in manganese ore ____________ _ 

27 

52 

54 

52 

9 

32 

32 

,.. 
~L'horium, In uJknllc Igneous rockS---

~l'ldes, effect ou surfnce-wu ter dh;-

Article 

27 

churge ---------------

'l'rlnsslc, Cullfornln, metu•morpblc 

46 

rocks---------------- 7 

Cnllforuln, new fossll collections_ 23 

Colorado, a(JlllfCI' tests_________ 44 

u 

Ultrnmu.fic rocks, magnetic anomalies 

OVCl' ---------------

UnderflOW, ground-water, benettth 

riverS----------------

Uranium, ln nlknllc Igneous rocks---

Urnnlum·vnnndlum deposits, effect 

of metnmorpbism on __ 

25 

36 

27 

26 

Artlcl~ 

Abrahams, J. H., Jr_______________ 3.7 

Adler, Isidore-------------------- 31 

Aker~ J. P--~------------------- 89 

Baltz, E. H---------------------- 311 

Bath, G. D----------------------- 25 

Bedinger, 1\f. 8-------------------- 35 

Brown, R J--------------------- 40 

Bull, \V. B----------------------- 19 

Cuemmerer, Allee ----------------- 27 

Carron, l\:1. IL-------------------- 3.0 

Clnrk, L. D---------------------- 6 

Cobbun, W. A-------------------- 8, 22 

Cohen, Phtllp -------------------- 4, 15 Cooley, 1\:f. Jll _____________ _:_:______ 18 

Coope~ J. B---------------------- 9 

Crippen, J. R-------------------- 45 

Curtis, W. 1!'--------------------- 14 

Cuttlttn, l!"'rnnl<------------------- 30 

Dodge, F. C---------------------- 7 

Drewes, Harald----------------~-- 1 

Eller, R C----------------------- 56 

li'ahnestocl<, R K----------------- 17 

Fcrnnld, A. T-------------------- 11 

Il'cth, J. H----------------------- 40 

Flunngan, F. J------------------- 81, 8~ 

Fros~ I. C----------------------- 28 

Glll, J. R------------------------ 8, 22 

Gottfried, David__________________ 27 

Grossman, I. G------------------- 55 

SUBJECT INDEX 

ArticleUtah, geomorphology, Colorado Rivet· 

system_______________ 18 

ground water, Great Salt Lake 

area------~---------- 40 

v 

Valley trains, ground water in _____ 41, 42 

Vnnudium, ln garnet______________ 26 

VIrgin Islands, St. Thomas, quality 

of water_____________ 26 

Virginia, Augustn County, geochem- istry ________________ _ 

Volcunlc ash, radiocarbon dating __ _ 

Volcanic rocks, chemical analyses __ _ 

metamorphosed --------------- Volcanoes, measurement of growth--

Volumetric shrinkage, sediments, relation to clay content_ 

AUTHOR INDEX 

27 

11 

10 

5 

20 

16 

Article 

Hamilton, \Varren ----------------

Haugen, R. T--------------------

Hardlson, C. H-------------------

Harris, D. V ---------------------

Hayes, P. C---------------------- Henrn, B. C., Jr _________________ _ 

Henry, H. R----------------------

Herrlck, S. 1\L--------------------

10,28 

20 

45 

17 

28 

12 

34 

21 

Imlay, R. W ---------------------- 6 

Irelan, Burdge___________________ 54 

Irwin, J. H---------------------- 44 

Invin, W. P --------------------- 23, ·25 

Jenkins, E. D-------------------- 44 

Johnson, A. 1--------------------- 16 

Kantrowitz, I. H----------------- 38 

Koopman, F. C------------------- 44 

Krlnsley, D. B-------------------- 24 

Landen, David------------------- 58 

Lang, S. M----------------------- 36 

Leonard, A. R-------------------- 52 

Leonard, B. F-------------------- 5 

Leopold, E. ~-------------------- 10 

:McKenzie, M. L------------------ 56 

1\fcl\:Iath, V. E-------------------- 6 

l\:lapel, W. J ---------------------- 13 

Mendieta, H. B------------------- 54 

Milton, Charles------------------- 12 

Moench, R. H-------------------- 26 

l\ioore, G. VV--------------------- 33 

Moore, J. 0---------------------- 7, 20 

Moore, Roosevelt_________________ 27 

l\forgan, C. 0-------------------- 50 

B-145 

w Article 

Weathering, effect on water-yielding· 

properties of crystalline 

rocks-------~-------- 48 

Wyoming, sedimentation, Black Hills, 

northern ------------- 13 

stl'Utlgrapby, eastern, Bla.ck Hills 

UtpltfL--------------- 8 

X 

X-ray fluorescence, analysis of silicate 

rocks ---------------- thallium ln mungnnese ore ____ _ 

y 

Yukon Territory, southern, stratigra- phy _________________ _ 

31 

32 

1l 

Article. 

Morris, D. A--------------------- 16 

Musser, J. J______________________ 53 

Nordin, C. F., Jr_________________ 14 

Norris, S. E---------------------- 41, 42 

Nygren, H. D--------------------- 3·3 

Pecora, W. T---------------------

Pillmore, C. L--------------------

Pluhowski, E. L-----------------

Purtymun, W. D------------------

Rantz, S. E----------------------

Reed, J. E-----------------------

Richter, D. H--------------------

Roberson, C. E-------------------

Rhodebamel, E. C----------------

Rose, H. J ., Jr ------------------- Rowe, J. J ______________________ _ 

Scher, M. B----------------------

Schneider, W. J __________________ _ 

Scott G. R-----------------------

Seaber, P. R----------------------

Silberllng, N. J ------------------- Speert, J. L ____________________ _ 

S[Jieker, A. 1\f--------------------

Stewart, D. B--------------------

Stewart, J. W --------------------

1'atlock, D. B--------------------

\Vallace, R. E--------------------

\Vnrd, P. E-----------------------

Wayman, C. H-------------------- \Vhetstone, G. \V ________________ _ 

Winner, 1\I. D., Jr _______________ _ 

\Vitkind, I. J--------------------

12 

1& 

38 

g,7 

46 

85 

20 

33 

36 

81,32 

48 

57 

47 

22 

51 

6,23 

59 

41,42 

29 

43 

2 

2 

52 

49 

58-

50 

3· 

U.S. GOVERNMENT PRINTING OFFICE : 1962 Q-629660