DEPARTMENT OF THE INTEKIOB

BULLETIN

UNITED STATES

GEOLOGICAL SURVEY

ISTo. 137

WASHINGTON

GOVERNMENT PRINTING OFFICE 

1896

UNITED STATES GEOLOGICAL SURVEY

CHARLES D. WALCOTT, DIRECTOR

THE

GEOLOGY

OF THE

FORT RILEY MILITARY RESERVATION Al VICINITY

KANSAS

BY

HOBEUT HA.Y

WASHINGTON

GOVERNMENT PRINTING OFFICE 

1896

CONTENTS.

Pago.

Letter of transraittal........................................................ 9

Topography ................................................:............... 11

Description of district ........................ ...^.............. 11

Kiver system.................................................... 12

Eepublican Valley.............................................. 12

Smoky Hill Valley.............................................. 13

Union of the valleys ..............^............................. 13

Creek valleys................................................... 13

Rnggedness of the topography . i................................ 14

The Kansas-Neosho watershed................................... 14

Sink-holes....................................................... 15

Neosho Valley .................................................. 16

Typical character of the district................................. 16

Geology .................................................................... 16

Paleozoic ............................................................... 16

Horizontal position of the strata..................................... 16

Fort Eiley section.................................................... 17

Description of strata................................................ 18

The Main ledge ................................................. 18

The Quarry beds................................................. 19

The Flint beds............ ...................................... 19

The mid-Shale bed.............................................. 20

The shales ...................................................... 20

Gypsum ........................................................ 21

Littoral and shallow-water conditions of deposition................. 21

Pre-Quateruary erosions............................................. 22

Continental uplifts ................................................. 22

Cretaceous............................................................... 23

Tertiary................................................................ 24

Quaternary............................................................. 24

Moraines...............i.........................^.............. 24

Occasional bowlders ............................................ 25

Loess .of two periods............................................ 26

Description of sink-holes ....................................... 26

Late Tertiary and early Quaternary contemporaneous............ 27

. Late Quaternary.................................................... 27

Gumbo ......................................................... 27

River alluvium; sand dunes..................................... 28

Baselevels...................................................... 28

Climatic changes ....................................................... 29

Correlation of different regions..................................... .. 80

5
6 CONTENTS.

Page.

Economic geology........................................................... 30

Soils.................................................................... 30

Bottom soils.................................. ............... 30

Upland soils.................................................... 31

Building materials...................................................... 31

Brick clays ..................................................... 31

Building stone.................................................. 31

Lime........................................................... 32

Cement......................................................... 32

Water supply........................................................... 32

Springs and wells............................................... 32

Measurement of rivers .......................................... 33

Paleontology............................................................... 33
ILLUSTRATIONS.

Page.

PLATE I. General map of the Fort Riley Military Reservation and neighborhood, Kans...................................................... 11

II. Profile and geological section across the Smoky Hill Valley at Junction City, Kans.................................................. 16

III. The Main ledge (limestone) in Wild Glen .......................... 18

IV. Stratified alluvium in river bank, Republican River, abutting against

loess and gumbo................................................. 20

V. Quarries on the military reservation above the Main lodge ......... 22

VI. Bluffs in Wild Glen showing turret-like weathering of the Upper

Flint beds ...................................................... 24

VII. Red bluffs (loess), Smoky Hill River, south by east from Fort Riley. 28 

VIII. Administration building, artillery post, Fort Riley, constructed of

the magnesian limestone of the district.......................... 32

FIG. 1. Loess bluffs on the Republican River ................................ 14

2. Map showing the region of sink-holes in northern Morris County .... 15

3. Diagram of sink-hole ............................................... 15

4. Section of the Lower Flint bods south of Parkersville, Morris County,

showing the layers of flint in the limestone ....................... 20

7

LETTER OF TRANSMITTAL.

JUNCTION CITY, KANS., February 15,1895.

SIR: I have the honor to transmit herewith, for publication as a bulletin of the United States Geological Survey, a report on the geology 

of the Fort Eiley Military Reservation, Kans., and the country surrounding it. Most of the work of which this report is the result was 

done as early as 1889. Delay in printing has led to the recasting of 

parts of the paper, but in only two particulars are there any important 

changes, and these involve the introduction of new matter obtained as 

late as the spring of 1893, concerning the Cretaceous (Dakota) deposits 

and the glacial moraines not many miles east of the district described. 

Acknowledgments are due for aid received in this survey to yourself 

and to Prof. W. J.McGee, as well as to Colonel (now General) Forsyth, 

commanding the post at Fort Eiley; to Lieutenant (now Captain) 

Fuller, regimental quartermaster; and to Capt. George E. Pond, of 

the staff of the quartermaster-general.

Yery respectfully, EGBERT HAT,

Geologist. 

Hon. CHARLES D. WALOOTT,

Director United, States Geological Survey.

U. S. GEOLOGICAL SURVEY. BULLETIN NO 137 PL. I.

GKNKKAL MAP

FOKT LEY MILITARY KESKRW OX I

AM) NEIGHBORHOOD

(.KANSAS.)

BY ROBKKT HAY".
THE GEOLOGY OF THE FORT RILEY MILITARY RESERVATION AND VICINITY, KANSAS.

By ROBERT HAY.1

TOPOGRAPHY.

Description of the district. The military reservation at Fort Eiley, 

Kans., occupies an area of about 20,000 acres, in Eiley and Geary 

(formerly Davis) counties. The northern half of its boundary approximates an arc of a circle. The southern half may be roughly stated to 

be the Eepublican and Kansas rivers, which unite at an obtuse angle 

near Junction City, though a small part of the reservation lies on the 

right bank of the Kansas Eiver. The area of the reservation was 

originally larger than at present. The old boundary is indicated on 

the map (PI. I) by a broken line which passes diagonally through the 

site of Junction City and incloses bottom lands between the Eepublican and Smoky Hill rivers. Very near the site of the military post 

these two rivers come together to form the Kaw or Kansas.2 The

1 This is a posthumous paper. It was written and submitted in the year 1889, but, owing to unavoidable circumstances, has remained unpublished. It was returned to Professor Hay for final revision 

in February, 1805, and this was probably the last work of -his life, for he died December 14,1895.

Since the preparation of the original manuscript ProfT Charles S. Prosser has made and published 

sections of the Carboniferous formations of the portion of Kansas discussed in this bulletin, 

giving paleontologic details of the Port Eiley section. (The Classification of the Upper Paleozoic 

Rocks of Central Kansas, by Charles S. Prosser: Jour, of Geology, Vol. in, Chicago, 1895.) By comparison of Professor Hay's section with Professor Prosser's classification the correct position of the 

Fort Riley beds in the Kansas, Carboniferous, and Permian series can be ascertained. According to 

Prosser the uppermost bed, No. 14 of Professor Hay's Fort Riley section, is probably the base of the 

Marion formation, the remainder of the section representing the Chase stage of Prosser's Permian 

section.

Professor Hay was an indefatigable worker and his contributions to the geology of the Kansas and 

plains region have been of great service. These were of a reconnaissance and introductory character 

rather than expositions of details, and although future work will greatly refine them, they have been 

of inestimable service, not only by their additions to our knowledge of the distribution and sequence 

of the formations of the plains region, but in many cases by reason of the new and original deductions 

they contain. His work was largely done in face of those obstacles which necessarily confront a 

scientific worker on the frontiers of knowledge, and his writings largely represent the product of 

voluntary research.

By a strange fatality, the opportunities for perfected publication of the two chief works of his life 

were interrupted. Just as the proofs of his report as geologist in charge of the special artesian and 

underflow investigation, conducted under the auspices of the Agricultural Department, were ready to 

be placed in his hands in Washington, he was called to his Kansas home to attend the last illness of 

his wife, who had been a constant and valuable assistant in his researches, and that report went to 

press without his final revision. It is a singular coincidence that his own death has prevented his 

seeing the proofs of the present paper. ROBERT T.-HILL.

2 The name Kansas will be hereafter used for this river in this report, in conformity with the ruling 

of the United States Board on Geographic Names.

11
12 GEOLOGY OF FORT EILEY RESERVATION, KANSAS.

northern part of the reservation is in Eiley County, but the post itself 

is in that part of it which belongs judicially to Geary County. The 

region described in the following pages which is outside the reservation includes the western half of Geary County and the panhandle 

comprising Milford Township, in its northwestern corner, with adjacent 

parts of Clay and Dickinson counties, to the ninety-seventh meridian. 

The thirty-ninth parallel passes about 6 miles south of the post. 

| The geology of the region, with the exception of that jof the Quaternary deposits, is comparatively simple and is typically developed within 

the limits of the reservation, owing to the very striking features of the 

topography. With the assistance of the map (PI. I) this topography 

will be easily described and readily understood.

River system. The topographic feature which first strikes the eye on 

an inspection of the map is the great fluvial system of the region. The 

rivers ranking in size as third and fourth in the State of Kansas the 

Eepublican and the Smoky Bill here, by their confluence, form the 

Kansas Eiver, the second river of the State. Geary County may appropriately be designated the County of the Three Eivers, for all the 

streams of the region belong to the Three Eiver system.

Republican Valley. The Eepublican Eiver comes from the northwest 

through a broad valley in which its stream meanders at a depth of 

from 8 to 15 feet below the general level of the bottom. The bottom is 

bounded on both sides by steep bluff's that are in places precipitous. 

Where their abruptness is not softened by slopes of Quaternary deposits 

the bluff's show ledges of limestone definitely continuous for miles. 

These bluffs are mostly over 100 feet high, and are surmounted by 

slopes that reach back from the valley to double that height, or more. 

To the traveler coming into the region these bluffs constitute the most 

imposing feature of the topography. The fronts of the bluffs are 

broken by the outlets of ravines, which, often formed by the union of 

several others in the plateau immediately behind, ramify to such an 

extent as to produce a very broken country for several miles back from 

the river valley, the ravines and draws being separated by ridges, 

mounds, and promontories of a pronounced type. This feature is indicated by the contours of the map, which show that it belongs to the 

whole region as well as to the Eepublican Valley. The abruptness of 

the sides of the main valley is more pronounced on the left bank of-the 

river, but diminishes on either side as we go toward the western limits 

of the district. This diminution of abruptness is due in nearly all cases 

to Quaternary deposits which are found buttressed against steep bluffs, 

making smooth upland at the heads of deep ravines. The river bottom 

north and northwest of Junction City, about 2 miles wide, is sandy and 

contains many true, wind-blown dunes. Most of these are now stationary, being covered with vegetation, and their regular arrangement 

testifies to the prevailingly southern direction of the winds during a 

long period.
HAY.] - TOPOGRAPHY. 13

SmolcyHill Valley. The topography of the Smoky Hill Valley is very 

similar to that of the Eepublican, with the distinction that it is the 

right side of the valley which has the steeper precipices and the more 

abrupt slopes. The resemblance is marked in the fact that abruptness 

on both sides sensibly diminishes westward within the limits of the 

district, and on the least abrupt banks of both rivers there is also a 

decided diminution at their lowest part, where easy slopes of Quaternary 

deposits may form a broad plain, as at the site of Junction City. The 

Smoky Hill has its bed mostly narrower but much deeper than that of 

the Republican, cutting into the Quaternary from 15 to 50. feet and in 

places reaching bed-rock.

Union of the valleys. The meeting of the waters of these two streams 

is at a very narrow part of the valley, not more than 1£ miles wide. 

The Eepublican, with long, sweeping reaches, has a general southwesterly direction, with the high wall of Sherman Heights to the north, 

which lower to a long promontory, and the coming in of the Smoky 

Hill from, the southwest has seemed to force the joint stream around 

another promontory, on which Fort Eiley is situated, to the northeast. 

The Kansas, taking a northerly direction, lies in a valley of rather uniform width in this region, being hemmed in by abrupt hills that rise 

150 feet directly from the valley, go 50 to 100 feet higher at very short 

distances back, and are broken into narrow ridges and long promontories by the valleys of the creeks and ravines immediately behind, as 

seen in Grant Cliff and Sheridan Bluffs. These ridges are at the same 

levels as well-defined plateaus seen in the distance beyond, and the 

most distant views show high prairie table-land nearly 400 feet above 

the level of the Kansas Valley. The sand dunes of the Kansas and 

Smoky Hill valleys are not so marked as those in the Eepublican, but 

the Smoky Hill side of the inesopotamian region has dunes near the 

high prairie level.

Creek valleys. The topography of the creek valleys is similar to that 

along the three rivers. There are abrupt bluffs on one side, and nearly 

level bottoms from a quarter to half a mile wide and smooth Quaternary slopes on the other side. The horizontal limestone ledges show in 

the steep cliffs like rows of giant teeth or mural defenses of cyclopean 

dwellers, and on the opposite side they crop out occasionally through 

the later sediments to attest their presence. On Lyons Creek and on 

Clark Creek the principal Quaternary deposits are on the west side of 

the valley, making long, smooth slopes to the western upland. In important tributaries of these streams Otter Creek, Dry Creek, and Humboldt Creek the eastern side is the smoother slope, though there are 

exceptional localities. The meandering of the creeks in their Quaternary beds is as marked as that of the most tortuous of the three rivers, 

which a reference to the map shows at once is the Smoky Hill. Where 

the circumvolutions are not so close as in other places, a straight line 

from the railway station at Junction City to the station at Fort Eiley,
14 GEOLOGY OF FORT RILEY RESERVATION, KANSAS.

a distance but slightly over 3 miles, would cross the Smoky Hill River 

three times and the Kansas River once. A similar line from the Fort 

Riley railway station to the northwest corner of Junction City would 

cross the Republican twice, the Smoky Hill once, and the Kansas once. 

A straight line can be laid that in 10 miles will cross the Smoky Hill 

thirteen times.

Ruggedness of the topography. The ruggedness of the district is 

nowhere more conspicuous than on the military reservation, where the 

headwaters of Three Mile, One Mile, and Four Mile creeks, Deep Dale, 

and Wild Glen begin in long draws in the upland, creating the phenomena of a rolling prairie, and then below a certain limestone horizon 

drop suddenly into deep ravines 75 to 150 feet deep, separated by the 

ridges and promontories previously described, many not more than a 

few hundred feet across. This ruggedness is perhaps due to erosion of

FIG. 1. Loess bluffs on the Republican River.

greater activity than now exists anywhere in the region of the Great 

Plains. The evidence is here decided that this configuration represents 

a period of time preceding the great Ice age.- Some things appear to 

suggest that this time was immediately pre-Glacial, but one or two 

facts seem to indicate positively that it was before the mid-Tertiary 

epoch. But the discussion of these phenomena may properly be 

deferred to the geological part of this report, with the observation that 

the ruggedness is still much modified by Quaternary deposits, which 

would appear to have once smoothed it over entirely. (See fig. 1.)

The Kansas-Neosho watershed. In seeking to make this report as permanently useful as possible, it seemed desirable to go beyond the limit 

indicated by the map, so as to connect the stratigraphy of the Kansas 

Valley with that of the Neosho, that correlation might be made of the
HAY.] TOPOGRAPHY. 15

GEAHY CO.

horizons which yield the so-called magnesian limestones for building 

purposes all across the State of Kansas. A rapid survey of the region 

of northern Morris County was therefore necessary, and the topography needs some description. Being at the headwaters of the principal creeks of Geary County, this region has rolling, high prairie 

surface, which is formed largely of Quaternary deposits and presents 

the phenomena known as sink-holes. The highest watershed separating Kansas Biver waters from the 

tributaries of the Neosho is here 

over 1,500 feet above tide, and broad 

depressions are formed where these 

phenomena exist.

, Sink-holes. Parts of the divide 

are as much as 4 miles south of the 

Geary-Morris boundary line, but 

toward the east the distance diminishes. In sec. 9, T. 14, B. 7 E., the 

sink-holes are very numerous, and 

in the northern half of the section 

to the south (sec. 16) they are as 

numerous in proportion to the. area. 

In section 9 that is, in 1 square 

mile forty-two were counted, and 

the exploration of that section was 

not such as to make it sure that all 

had been seen. A single example is 

also found in section 30 in the same township i. e., 3 miles south and 2 

west. The subsoil of the high prairie is loess, or a modification of it, and 

owing to long-continued vegetation the humus is several feet deep. It 

is in these that the sink-holes exist, sometimes showing a ledge of bedrock in their sides, and almost uniformly loose stones from 20 or 30 pounds 

to 100 or 200 pounds in weight are in the center of the depression.

The sink-holes are mostly oval in form, but a few are nearly circular. 

One of these measured 30 feet one way and 28 feet transversely; others

were nearly 50 

feet by 30 to 35 

feet. Some

7i ^^ -"^ show no stones, 

owing to the 

falling in of the

FIG. 3.-Diagram of sink-hole. sides > but a stick

inserted down

the middle meets with stony obstruction about 2 feet below the visible 

bottom. The bottom material of all of them is loose in arrangement, 

and two of them have low trees growing in them. The depth is remarkably uniform, none less than 8 feet, none over 10 feet. Some of them

HM6f 7 EAST.

TIG. 2. Map showing the region of sinkholes in northern Morris County.
16 GEOLOGY OF FORT RILEY RESERVATION, KANSAS.

are single, but usually there are more than one in a large depression 

five in one instance, three and two commonly. A few small areas otherwise resembling sink-holes have standing water in them. They apparently are sink-holes in which the mud has become a clay puddle, 

checking subterranean drainage. The sink-holes proper carry away 

underground all the water that runs into them.

Neosho Valley. The main valley of the Neosho becomes rapidly 

deeper at the same horizon which marks that phenomenon in the Three 

Eivers region, but the ruggedness of the confluent valleys is not nearly 

so pronounced as in the more northern district.

Typical character of the district. The ruggedness of the Fort Eiley 

district is typical of a much more extended area stretching across 

Eiley, Pottawatomie, and Wabaunsee counties, and far to the north. 

It may be attributed to pre-Glacial erosion, the modification of which 

may as certainly be attributed everywhere to Glacial and post-Glacial 

deposits. It was because of this typical character that some details of 

the topography have been dealt with somewhat more minutely than 

would be necessary for the treatment of a larger district, and the same 

is true of the descriptive geology that follows.

GEOLOGY.

PALEOZOIC. 

HORIZONTAL POSITION OF THE STRATA.

We have said that the geology is simple, corresponding with.the 

topography. A prominent feature is the increase in number of deposits 

westward, new formations coming in above, giving increment of elevation in that direction. Its strongest feature, however, is the almost 

horizontal position of the strata. There is some variation of the dip, 

but the general dip for the whole region is west-northwest. In parts, 

however, it is to the southwest, and small folds show a westerly uplift. 

There seems to be evidence of slight depression toward the stream 

valleys, indicating small synclines as the basis of the original drainage.

West of Chapman Creek, in Dickinson County, and up the Eepublican in Clay County, the flint beds again crop out, showing that there 

is a north-and-south trough of a syncline of considerable extent and 

of some depth, but the details have not been made out. The average 

west by north to northwest dip is probably not more than from 10 to 

15 feet to the mile, or 0° 10', but local variations are as much as 3£ in 

600, or 0° 25'. One of these to the south and west of One Mile Creek 

which gives easterly dip is conspicuous in the railway cutting on the 

river bank at Fort Eiley. This brings into view $ome of the lowest 

strata in the district, so that on the military reservation may be seen 

the outcrop of three-fourths of the more than 300 feet of deposits 

which come to the surface in this region. It is therefore appropriate 

to name this series the Fort Eiley section. It is as follows:
U.S.GEOLOGICAL SURVEY BULLETIN N9 137 PL.II.

SKETCH OF JUNCTION CTTV

Showing, po.sition.of profile - 

AND'WETVLS (W).

liarJiurKd Contoitrsfumsa/Jfii-admatefy 

VE5//>v theoutcropofNo.il oftAf.Gcntagi'XilSection,

' '! ^iHiffhttmd 

Cviittay

LEGEND: The-numbers on. the-right (SASTjof the section arc. those oftheStratain,(Ji&FortRiley Section., a., sand; b, joint clay (Quaten^iry); 

c, river alluti.tim,, mostly sand; g, gravel with water; A, outcrop of 

a, cretaceous outlier (Dakota, sands). Sections of the salt wells is from, a 

newspaperreport in, 1877 of a. boring mat/.e in, L873. It consists entirely 

of shales and, limestones after 46 feetofalluA-uwr,.

JULIUS BIEH 3 CO
HAT.] THE STEATA.

Fort Riley section. 1

17

N

Permian.

arboniferous.

0 

6

|

PH

».

14

13

12

11

'10

9

8

7

6

5

4

3

2

'

Strata.

Impure limestones,2 with some flints

and numerous geodes.

Light-colored shales, with lavender

flag beds.

Blufl' limestones, with shale partings,

changing to shales with limestone 

ledges.

The Fort Riley Main ledge: a buff

magneeian limestone in one thick

ledge, with a thinner ledge resting

on it; in places the layers are continuous into the layers of 12.

Shales, light-colored and laminated..

The Upper Flint beds: limestones

containing numerous flint nodules

and separated by definite layers of

flints. 

Shales, alternate colors,. gray, greenish, maroon, brown.

Limestone : the mid-Shale bed, varying from a laminated, flaggy layer 

to a solid building stone.

Shales, alternate colors, as No. 8 ......

The Wreford limestone,3 the Lower

Flint beds: flints as in No. 9; parts

of the beds are silicified in localities as if by infiltration. 

Shales, bands of maroon and greenish-gray, with a seam of coal on

Humboldt Creek. 

Limestone, in cuboidal or rhomboidal

blocks; in places oolitic; a seam of

coal under it on Humboldt Creek. 

Shales and buffy "slate"...... ......

"Slate," bluish and hard...... .......

Fossils.

A univalve ...... .... ....

Athyris, Pecten, Pleurophorus.

Pecten, Nautiloids, Athyris, Meekella', Hernipronites, Marti nia, 

Fenestella, Synod adia, 'Schizodus.

Pecten, Allorisma, Martinia, Athyris, Eetzia,

Heniipronites, Syiiocladia, Feuestella.

Producti , Allorisma,

.' Chonetes.

Producti, Chonetes, Allorisma, Martinia.

Planorbis and another

univalve, Allorisma, 

Meekella, Myalina, 

Heniipronites, Producti, etc. 

No fossils.... ............

Criuoids, Syntrilasma,

Athyris, Eetzia, Pinna,

Meekella, Producti,

cup-corals.

Occasional Discina ......

Thickness.

Feet. 

10

50-60

30^0

6

15

25-30

30

6

16

25

16 .

4

10

10

»The Chase formation of Prosser. R. T. H. « Probably the Marion beds of Prosser. R. T. H. 

3 Strong flint of Prosser. R. T. H.

Bull. 137 2
18 GEOLOGY OF FORT RILEY RESERVATION, KANSAS. 

Fort Riley section 1 Continued.

No.

be- areisborder st

ict.

2'S|

o o> £ *= jg 'o 2^ ® °13A ® a *> £§<H A ^° 

H

. Strata.

sum.

Fossils. Thickness.

Feet. 

30

5

» The Chase formation of Prosser. R. T. H.

DESCRIPTION OP STRATA.

The Main ledge. The most conspicuous feature of the topography of 

the district is the outcrop of the massive limestone we have numbered 

11 and named the Main ledge. Its topographical importance was 

remarked by Dr. Hayden nearly forty years ago. It is a buff, soft, 

magnesian limestone, yielding easily to the tools of the mason, but 

hardening on its exposed surfaces. While not conspicuously fossiliferous, except in certain localities, it has in the aggregate many fossils, and it also contains small cavities, now partially filled with calcite, 

which are apparently due to the former presence of fossils. These 

form imperfections in this rock as a building stone, but its durable 

quality and the thickness of its bed 5 to 7 feet have caused it to be 

used where large blocks are required. The east wing of the capitol at 

Topeka was built from quarries at Junction City in this ledge, it being 

the first limestone in the State that was observed to yield large blocks. 

Grant Cliff and Sheridan Bluffs, on the Kansas, and Sherman Heights, 

on the Eepublican, show this ledge conspicuously, the exposure last 

named being several miles in length. The limestone may be seen on 

both sides of the Smoky Hill and toward the head of all the creeks to 

the south. Its conspicuous position in the topography suggests the 

use of its name in the geological nomenclature of the region, for we 

may divide the deposits generally into two groups those above and 

those below the Main ledge of limestone, the Main ledge itself belonging to the upper group. It is the Main ledge which we mentioned as 

the certain horizon, below which the topography is more rugged. It 

follows, then, that, though the lower group of strata is thicker than 

those developed above it, the areal exposure of the higher group is 

greater than that of the lower its slopes are gentler, its valleys less 

profound. In going westward the increment of the formations upward 

is most marked in the great valleys, but each formation is found farther 

east at some distance back from the streams.
U. 8. GEOLOGICAL SURVEY 

THE MAIN LEDGE (LIMESTONE) IN WILD GLEN.
HAY.] PALEOZOIC. 19

The first appearance of the Main ledge in the Sheridan Bluffs in the 

Kansas Valley is just below the old town-site of Pawnee. Plate III is 

a view of a typical exposure, showing also the stratum next above it. 

The view of Sherman Heights shows its position in the Eepublicau 

Valley with 100 feet of other strata resting on it (see PI. IV). It has 

very little areal exposure anywhere in the region, the largest areas 

being farther east and south of the river. Besides being conspicuous 

in the topography and stratigraphy of the region, the Main ledge seems 

to have paleontologic importance. It appears to be the upper limit of 

the Productidse. On the south line of Geary County we have found 

specimens of Productus semlreticulatus lying loose on the Main ledge, 

but in no other place have we found Producti above the shaly material 

at the base of that stratum. The specimen referred to might have 

been transported from a horizon only a few feet lower geologically and 

at a decidedly greater altitude only a few miles away.

It will be convenient to speak of this as the Main ledge, while its 

identity for comparison with other work in the State will be best established by its number (11) in the Fort Eiley section.

The Quarry beds. The beds immediately above the Main ledge may 

be spoken of as the Quarry beds. Throughout all the region they yield 

good building stone, easy to work and of soft, warm tint, in layers from 

6 to 18 inches thick, of jointed structure, which give masses 6 to 12 

feet long and 3 to 5 feet wide. The shale partings thicken in places 

to shale beds several feet thick, and the stone changes to shaly flags 

with rhomboidal fracture, passing upward sometimes into a lavender 

shale of the hard kind, locally called slate, or into massive beds with 

hydraulic properties, as at Milford. These beds may be altogether 50 

feet thick, above which shales predominate, with occasional ledges of 

stone, of which only the highest is numbered, and which attains the 

thickness assigned to it in the section only west of the ninety-seventh 

meridian, somewhat beyond the limits of the district. The geodes in 

this bed (No. 14), which is developed in force on Chapman Creek (11 

miles west of Junction City), and also south of the Smoky Hill at 

the same meridian, are accompanied by cherty nodules, which are the 

source of the flinty (cherty) gravels occasionally found above the Main 

ledge.

The Mint beds. The two series of Flint beds, Kos. 5 and 9 of the section, form a quite important part of the stratigraphy of the region and 

of much of the country to the east and south. The name flint is used 

designedly. The material appears to be much more siliceous than the 

chert of southeastern Kansas and Missouri. It appears undistinguishable from the flints of the Cretaceous formations of England. The 

greater part of the beds consists of limestone, through which the flint 

is scattered in globular, ellipsoidal, and irregular nodules, with one or 

two bauds of black and white near their surfaces. Besides the irregularly disposed nodules, there are flint layers 3 to 12. inches thick
20 GEOLOGY OF FORT RILEY RESERVATION, KANSAS.

between the limestone layers. Fig. 4 is a section on the Neosho in 

Morris County, which shows a little more than the average amount of 

flint farther north.

The presence of the flint serves to give a hardness to these beds, 

which, however, does not hinder their disintegration; for, under the 

influence of frost the flints themselves split into many fragments, with 

conchoidal, splintery, and smooth fracture; but under certain conditions of exposure the broken flints acquire a vitreous surface and cease 

to break, and so form surfaces that slowly acquire a sedentary soil. 

Both series of flint beds, and also the Main ledge, frequently form 

vertical exposures, while through the wearing away of the shales 

beneath they overhang and topple over in large masses. On some 

faces there is a turret-like weathering which is peculiar (see PI. Y).

The.mid-Shale bed. The bed No. 7 in the section is very variable 

in structure. In some places it is only a laminated shale with vertical

fracture, in others it is a flaggy

shale with one or two layers of real

FLINTS flags, and again it becomes a corn-

£LIMESTONE ,\. , -i. *n f v. -nv pact limestone suitable for building

purposes and massive through its 

whole thickness. In Eagle Ravine, 

southwest from Junction City, this 

bed there 3 feet thick is occasionally oolitic.

The shales. The colored shales, 

Nos. 6 and 8, are not variegated, but 

are beds of different colors alterSome are purplish-brown, Fm. 4. Section of the Lower Fliiit beds south of 

Parkersville,Morris County, showing the layers others green, and SOUie red-brown, 

of flint in the limestone. each ^^ varying Qn exposure.

The bauds are from 3 inches to 2 feet in thickness, and the gray-greens 

exceed that. One of the red bauds seems to be of the texture for mineral paint. There are con spicuous outcrops, vertical exposures, of parts 

of these beds at the water-mill on the Smoky Hill, at Fort Riley railway cut, and at other places. Shales that occur below these beds are 

mostly lavender or greenish, and those above the Main ledge are Avith 

few exceptions the same. "Where the shales have areal development 

they form a cold, intractable subsoil, which, hoAvever, has by longcontinued growth of vegetation become in places a fertile humus.

The strata thus briefly described belong to the later part of the 

Carboniferous epoch. They are nearly at the top of Kansas Paleozoics. They have a facies, in the limestone, that is not found east 

of Manhattan in the Kansas Valley, but which appears at corresponding positions farther north and south. This may be called the Permian 

facies. The limestones of the Coal Measures to the east are harder 

and rougher, and rarely have the milky or buff hue that prevails here. 

With the possible exception already mentioned, the "Producti are not
U. S. GEOLOGICAL SURVE 

^^T^^T^^

STRATIFIED ALLUVIUM IN RIVER BANK, REPUBLICAN RIVER, ABUTTING A
21

found in the higher beds. But without reference to the paleontology, 

there is a lithological reason for distinguishing these from the Coal 

Measures horizons which outcrop to the east. And yet Coal Measures 

characteristics-come up into these beds. On Humboldt Creek, just at 

the eastern limit of the district, in lower shales, is a seam of coal 12 

inches thick, and a few miles away is another at a slightly higher horizon. It is not of good quality, and is at probably the highest horizon 

in the west. The blue slate, No. 1 of the section, is similar to beds 

at much lower horizons, and contains occasional Discinoe. The term 

Permo-Carboniferous, though cumbrous, seems fully justified for the 

series below the Main ledge, while ISTos. 11 to 14 might properly be 

called Permian. There is no break in the succession of the strata from 

the Coal Measures below.

Gypsum. Below the beds of this section, in shales which preceded 

them, there is a gypsiferous horizon, revealed in wells. It is found on 

Clarks Creek, in Junction City, and on the military reservation. The 

gypsum occurs as satin-spar from half an inch to 2 inches thick, and in 

thicker, seinitrauslucent, crystalline masses. The exact horizon of the 

gypsum has not been made out, but there may be more than one, or it 

may be distributed all through a thick bed of shale the miner's soapstone. At a still greater depth strong salt brine was reached some 

years ago in a deep well at Junction City.

LITTORAL AND SHALLOW-WATER CONDITIONS OF DEPOSITION.

The strata described above, of various texture, suggest diversity 

of origin. Occasionally the flaggy layers show ripple-marks, and there 

are univalves among the fauna that suggest a shallow sea. The higher 

beds also have abundance of Pecten, and, outside the district, a small 

Pleurophorus, that testify to the same fact. On the other hand, the 

uniform thickness of some of the limestones, their fine grain, and the 

still finer grain of some of the shales, suggest deposition in deeper 

water. There is no extended sheet of faunal remains like the enormous 

shell beds of the Cretaceous epoch or "the coral reefs of the mouutain 

limestone, which indicate uniform and moderate depths over great areas. 

Yet, there is one horizon that perhaps suggests littoral conditions for 

the time of its deposit. This is the horizon of the Upper Flint beds 

(No. 9). Apparently, this is the most persistently fossiliferous horizon. 

There are numerous Product]. One bed, less limy than the others and 

without flints, has Producti all crushed and Hemipronites in fragments. 

In the thicker beds the shells are less numerous, but they are not distorted. Again, fossils having the internal structure of Producti are 

more numerous in these flints than anywhere else, so far as known to 

the writer. Synocladia and Fenestella are found both in the Flint beds 

and above. The 'Lower Flint beds (No. 5) show similar conditions, while 

the fossils of No. 7 are allied in the predominance of lamellibranchs to 

the beds above the Main ledge (Nos. 12 and 13). Farther west and
22 GEOLOGY OF FORT RILEY RESERVATION,

north the highest Paleozoic beds contain a horizon of massive and semicrystalline gypsum, which may be regarded as certainly a shallowwater deposit. Considering all the phenomena alluded to above, it 

would seem to be fairly established that these beds were deposited 

on a nearly level sinking sea-lioor, the sinking being at a variable 

rate, allowing some beds to be deposited in water deep enough to be 

free from aerial disturbance and others to be laid down under littoral 

conditions.

PEE- QUATERNARY EROSIONS.

The present slope of these beds, their close approximation to absolute levelness, and the enormous amount of their erosion need some 

remarks. Within 20 miles west of the western boundary of the district under consideration, and also in places northward, and notably 

in a small area in the district itself, formations of Cretaceous age 

(Dakota) rest on the Carboniferous beds with erosive unconformity. 

It follows, then, that these last of Paleozoic rocks were elevated above 

sea-level and subjected to the action of aerial agencies during a large 

part of early Mesozoic time, probably all through the Triassic and 

Jurassic epochs.1 That they were then submerged to receive the 

Dakota formations upon them in northern Kansas and Nebraska to a 

distance much farther east than is now known in the Kansas Valley is 

certain from a consideration of the Cretaceous deposits yet to be described. This being so, there was since the Cretaceous submergence 

another period of uplift and subaerial erosion before the middle Tertiary 

period, and in that time the valleys were carved in their present lines 

and nearly to their present depth. On this subject the evidence is 

meager in quantity but apparently positive in quality. In one place 

only is a thin fragment of conglomerate that is manifestly related to, 

if not identical with, the Tertiary conglomerate of western Kansas, 

which is considered to be the Loup Fork Miocene. It rests on shale 

below the Lower Flint ledge on the steep side of the Smoky Hill, east 

of Junction City, and has been exposed by excavation for enlarging 

the roadway at the water-mill. Higher up is a bed of the Tertiary 

marl, and on the same slope is a large deposit of loess; and a little to 

the north, and again in the Kansas and Eepublican valleys, the loess 

in places comes down into the bed of the stream, and is also found in 

all ravines and at heights of nearly 300 feet above the river valleys.

CONTINENTAL UPLIFTS.

Assuming continental depression in the Glacial epoch as the cause 

of the submergence in which the loess was deposited, and that this 

occurred only once, it would appear that since the deposition of the

1 This applies only to northern Kansas. Farther south it seems demonstrated that 1,000 feet or more 

of red-bed and saliferous shallow-water deposits came with stratigrapluc continuity upon the PermoCarboniferous rocks and connected Paleozoic with Mesozoic formations.
BULLETIN NO. 137 PL, V

E MILITARY RESERVATION ABOVE THE MAIN LEDGE.
HAT.] CRETACEOUS. 23

\

Permo-Carboniferous strata there have been three periods of uplift and 

two of depression of the entire area. It would also appear that this 

upper Kansas Valley region has in these oscillations of level been very 

gently dealt with. Carboniferous strata in southeastern Kansas show 

a few faults; Cretaceous strata in the northwest are similarly broken; 

but the writer has seen no rupture of stratification in any part of the 

region under discussion. The folds indicated in places by the different 

dips on the opposite sides of the great valleys, and the greatest dips 

seen in a few short sections, are so small as to excite wonder that so 

many changes of level, aggregating a total of thousands of feet, should 

have been accomplished with so little disturbance of the strata. It 

has been remarked above that the slight average dip of 10 to 15 feet to 

the mile is to the north of west, and as farther east the-dip is increased, 

it may be assumed that it is connected with the Ozark uplift, and any 

elevation in Tertiary times that may have affected this region as the

Kocky Mountain uplift only decreased and did not obliterate the 

westerly dip. The most noticeable dip of the region, an easterly one, 

is seen in the railway cut at Fort Eiley, and a short fold is seen in the 

Main ledge near the confluence of Otter and Lyons creeks, on the east 

side of the valley. Similar short folds are suggested rather than seen 

in the position of the ledges on the sides of rocky gullies where the 

harder beds are partially eroded.

CRETACEOUS.

Allusion to the existence of fragments of Cretaceous (Dakota) and 

Tertiary deposits has already been made. Some of the former are so 

very small mere patches of gravel composed of nodules from the ferruginous sandstones that they are not indicated on the map (PI. I). 

One of them is in the roadway on the hilltop near the Catholic cemetery, southwest of Junction City. Six or seven miles west of this 

point masses of the dark-brown sandstones have been turned up by 

the plow. A more recent examination of the high-level sand dunes 

previously referred to revealed the fact that they are residual beds, 

resting on and abutting against undoubted outliers of the Dakota. In 

sec. 21, T. 12, E. 5 E., are two small areas of the rough sandstones in 

situ, both on slopes of rather deep draws, but where tall bunch grasses 

and blue-stem hide the rock from observation unless one actually 

walks on them. On neighboring parts of sections 16 and 17 the soft 

sandstone developed 20 miles to the northwest, on the Clay-Dickinson 

county line, is shown in round-topped mounds or promontories, having 

their elongations from north to south and their free ends to the south. 

All these are in a hollow of the Permian formations, the limestones 

outcropping at higher levels to the east. The incoherent sandstone 

has been preserved in situ by the amount of its own d6bris lying on 

its sides, now covered with vegetation, and to the north some of the 

wind-blown sand rests on Permian strata. For several miles west the
24 GEOLOGY OF FORT EILEY RESERVATION, KANSAS.

soil is entirely arenaceous, and is undoubtedly sedentary on the sandstones of which it is the d6bris. This discovery of an area of several 

square miles of an outlier of the Dakota on the north side of the Smoky 

Hill so far east, has suggested that a univalve obtained in an arenaceous limestone on the top of the hills on the south side of the river 

may be Turritella from a Mesozoic rock, but opportunity has not been 

had to verify this suggestion, as the fossil is not now in my possession.

TERTIARY.

At the junction of the two rivers, near the military post, the beds of 

the streams contain gravel composed largely of pebbles of igneous rock 

that make up the Tertiary conglomerate of western Kansas and the 

neighboring parts of Colorado and Nebraska. Under the alluvium of 

the Eepublican Valley, about a quarter of a mile from the river, the 

new wells supplying water to the fort obtain it from a gravel of the 

same material. These, like patches of Dakota d6bris embedded in 

the Quaternary, are manifestly the results of the erosive and transporting power of the great rivers. But a patch of gravel with a hard 

layer of cemented concrete at the bottom, lying within this area, east 

of the ninety-seventh meridian, seems to be a fragment of the Tertiary 

grit of the West, in situ. It is more than 30 miles farther east than 

the most easterly extension of this formation hitherto noted in Kansas. 

In this case most of the pebbles are subangular ones, of the Flint beds 

of the district, with a vitreous surface, but running through the patch 

is a large quantity of quartz pebbles well rounded and small, with 

some feldspar in a limy matrix, which holds parts of it as a firm conglomerate, and there are also chalk pebbles and the hard chalk nodules 

characteristic of the Tertiary " mortar beds." The deposit rests on the 

banded shales (No. 4 of the section) below the Lower Flint beds, and is 

 within 30 feet of the bottom of the present river bed, here cutting bedrock. It is possible that the deposit is not actually of Miocene age, 

but it is certainly pre-loess, for a typical deposit of the loess rests upon 

it, and near to it and above not above the loess is a bed more resembling the Tertiary (Pliocene) marl of the West than it does the loess 

near to it.

QUATERNARY.

Moraines. Less than 20 miles from the northeastern limit of the 

district under consideration what seems to be a terminal moraine of 

the Ice age exists on the top of Carboniferous bluffs overlooking the 

Kansas Valley below St. George. It is in the shape of a large deposit 

of bowlders, mostly of the red quartzite so common in northeastern 

Kansas and western Iowa. There is also on the south side of the 

Kansas Biver, southeast from St. George, a magnificent development 

of terminal moraine. It is the southwest corner of ice-land. The 

trough of the Blue Eiver and the pass over the divide which the Eock
U. S. GEOLOGICAL SURVEY BULLETIN NO. 137 PL. VI

 "' " " - '

"' >:'^"h ^

 " ;:"i'>"y£~'*.:>iwr.;;?*^ *:> "_,r/:?-"'-'" * ' ''

 l\i (' ti " ("(i p«if-'"''W 1' %ww^'^/;^'^^ 4(/l/a^fc., - " -r^-ir.^:;r'*-i*-i'Si«wi

BLUFFS IN WILD GLEN, SHOWING TURRET-LIKE WEATHERING OF THE UPPER FLINT BEDS.
HAT.] QUATERNARY. 25

 -XM . .

Island Eailway uses from the Kansas Yalley to Mill Creek were probably cut or largely deepened by the waters running around the ice 

front which here dammed the Kansas. If the ice was 500 or 600 feet 

thick it would be sufficient, without assuming continental depression, 

to send the loess-bearing waters to the top of the Kansas-Neosho divide 

on the Morris County boundary, where loess is found in quantity. 

With depression in the ice region the ice would have been thicker. In 

the Fort Eiley district, here treated of, are no such .deposits of bowlders, 

but the eastern limit of this investigation is only 20 miles from the 

region where the bowlder-laden ice had its front. It appears to be 

demonstrable that the loess of this district is a deposit of the true 

Glacial age from the water of the great rivers of the North deflected 

around the ice front and reinforced by the rivers on and under the ice 

sheet.

Occasional bowlders. A phenomenon of the entire period when the 

region was submerged in the cold sea, during both the advance and the 

retreat of the ice, would be the occasional floating off of bergs containing bowlders and the melting out of their load at distances from the 

usual termini of the ice. The positions of bowlders in loess well within 

the true ice region in northern Kansas admits of no other explanation, 

and when bowlders are found beyond the known limits of the ice, it 

appears certain that this dropping from wandering bergs is the true 

source of the erratics. Three bowlders have been obtained in the Fort 

Eiley district. The smallest is 2£ pounds in weight, the largest about 

10 pounds. The two smaller ones are the red quartzite; the largest is 

a pink granite. The smallest was obtained on Three Mile Creek, on 

upland prairie, in the sod; the second was obtained in loess on the 

right bank of the Smoky Hill, east of Junction City; and the granite 

was found in the loess excavated for the sewer at Fort Eiley. These 

testify to the presence of ice in the district, however small the quantity. 

The comparative rarity of them in a westerly direction from the ice 

front indicates that the trend of the,water currents was to the southeast. On a hill 6 miles south of Junction City, on the west of Lyons 

Creek, a surface layer of limestone has deep, definite grooves on its 

weathered surfaces. Similar marks are seen in a few other localities 

under the same conditions of exposure. They are not distinctly ice 

strias, like those in the glacial regions around the Great Lakes, and till 

further research is made it may be prudent to doubt their glacial origin. 

Should it be eventually decided that they are glacial strias, it would be 

proper to attribute them to the action of bergs grinding their way 

across the ridges on which these marks are situated. The marks have 

weathered edges, and if it be true that the ice of Kansas was of the 

first period, before the inter-glacial amelioration, it would be wonderful 

that any striaB should survive the weathering agencies of so long a 

time, and those not actually obliterated would naturally have such 

blurred edges as to suggest doubt concerning their origin. Such, is the
26 GEOLOGY OF FORT EILEY RESERVATION, KANSAS.

condition of these marks, and the writer has for a long time rejected 

any suggestion that they may be glacial, but it would appear to be 

proper to put on record the fact that the marks exist. 1 '

Loess of two periods. The presence in loess deposits of bowlders 

more or less angular, such as the three mentioned above, seems demonstrative of the fact that the loess and the ice are of the same age. The 

ice being assumed to be that of the first Glacial epoch, it follows that 

the loess is also of that age. Professor McGee and others are of the 

opinion that the loess of the Missouri Valley and of parts of the Kansas Valley is of the second Glacial period. Within the limits of this 

investigation, and notably on the military reservation, there are decided 

differences in deposits which the observer, considering each separately, 

regards as loess. Some of these differences seem explicable by assuming modification of a deposit in situ by saturation and disturbance by 

floods of comparatively recent date, or even by ordinary percolation of 

meteoric waters. That some beds of loess have been so modified is 

manifest in railway cuts and other vertical sections, but such influences 

cease a few feet below the surface. But there are places where vertical 

sections show that an entire deposit is different from another close to 

it and which must have been subjected to the same influences in recent 

times. An example of this is seen near the mouth of One Mile Creek, 

where there are two bluffs fronting the river, each cut by the railway 

to the same depth. One is of bright-orange color and arenaceous in 

texture; the other is more argillaceous and of decidedly duller hue. 

It would seem that we have here loess of both the earlier and the later 

epochs together. The relative age can not here be made out by superposition, but the totality of the evidence in the district is that the 

brighter-colored loess is the older deposit. Of this bright-colored 

loess there is an abundance all through the region, from the lowest 

stream beds to the highest plateaus. In the more westerly part of the 

region, besides having streaks of gravel of the local Carboniferous 

limestones it has streaks and patches of the unmistakable detritus of 

the Dakota sandstones, and it would seem that that formation is, by 

degradation, the source of the coloring matter of the loess, as farther 

south the Triassic "red beds " have colored the loess of large areas.

Description of sinJc-holes. In connection with the fact that the loess 

is found on the plateaus, it is well to recur to a consideration of the 

structure of the sink-holes which have been referred to in the topographical description. The structure of these depressions is fully 

revealed in the single one in section 30. It is just off the line of a 

"draw," in what seems to be the course of a branch draw which has 

an earthwork dam across it. This makes a little basin, in the middle 

of which is the sink-hole. This basin is about 150 feet in diameter, and the sink-hole is about one-fifth of that. On one side of the

 The marks on Lyons Creek were brought to the writer's notice by Mr. E. McCarthy, county commissioner of Geary County, on whose laud they are, and who for years has considered them as 

certainly of glacial origin.
QUATERNARY. 27

sink-hole, jast at the top, a ledge of rock crops out, and in the bottom 

are many loose rocks. The diagram on page 15 (fig. 3) illustrates it.

A few rods down the main draw the principal ledge of rocks (No. 11 

of the section) shows itself in the descent to the Neosho. The ravine 

here is filled with alluvium from t the upland, and is so wide between 

the exposures of the Main ledge as to suggest that before the alluvial 

filling it had been cut down to other rocks, the Upper Flints, or lower 

still. The bottom of -the sink-hole is only a few feet above the Main 

ledge, and the suggestion is that under it the Main ledge is cut away, 

and that the under-draiuage is in d6bris of that and the Flint beds; or 

it is not necessary to assume that the Flint beds were eroded out, but 

simply that they were cracked and the shale partings worn where the 

surface was exposed. The great group of sink-holes lie much higher 

than this one, and the rocky debris in them is probably of beds higher 

than the Main ledge. The appearance of the nearest outcrop to the 

north suggests that IsTo. 14 is here below the level of the sink-holes. 

Deep road ruts and plowed slopes show that this high Kansas-lSeosho 

watershed is covered with loess from 5 to 15 feet thick. The underdrainage is in d6bris and broken surfaces of the upper Permo-Carbouiferous rocks. The Kansas-Neosho divide in pre-loess times was very 

narrow, with rocky gorges on each side to the very top, and the filling 

of all these with loess high above the former ridge, to a height of which 

the present residue is over 1,500 feet, provided the conditions for the 

sink-holes, owing to the semicavernous character of the rocky debris 

underlying the loess.

It may be stated that 10 miles farther south there is another series of 

sink-holes, farther outside the true glacial area, and others again 70 

miles to the north which are well within the region of undoubted glacial 

phenomena.

Late Tertiary and early Quaternary contemporaneous. On the western 

borders of this district, and to a greater extent beyond the ninetyseventh meridian, there are beds which, by their color more inclined to 

buff than orange their calcareous composition, and the presence of calcareous nodules, seem to be formed by a mingling of the loess and the 

materials of the Tertiary marl (Pliocene) of the Western plains, and a 

few fragments are certainly remnants in situ of that deposit. The juxtaposition of these deposits suggests, as has been noted by others, that 

the so-called late Tertiaries of the West were contemporaneous with the 

so-called first Quaternaries. A full examination of the superficial 

deposits in eastern-central Kansas will reveal much on this subject.

LATE QUATERNARY.

Gumbo. The valleys of the great rivers contain recent alluvium, as 

do also the creek valleys. There is one alluvial deposit having a large 

areal development that requires some notice. Its position on the site 

of Junction City is shown in the profile (PI. II). It must be considered
28 GEOLOGY OF FORT RILBY RESERVATION, KANSAS.

a lake silt, which was deposited when the valleys were still flooded 

from bluff to bluff. .It is known locally as gumbo, joint clay, and hardpan, though it is not the well-known waxy hard-pan of the true glacial 

region. The second name is descriptive, as in drying it breaks with 

subcuboidal fracture, and it is a clay of a dull-brown hue. It overlies 

the loess on the Junction City site and elsewhere, and it underlies the 

sandy alluvium of the great valleys and some of the smaller ones. It 

represents conditions of deposition that exist now only at long intervals, .when floods leave muddy waters to deposit their fine sediment in 

old creek and river beds. When the gumbo was laid down there must 

have been wide expanses of quiet waters over great valley areas. It 

probably had its origin when the. lake waters were, on their margins, 

eroding the clay-shales, both within this region and far to the west 

among the Cretaceous formations. It is of very tenaceous texture, and 

is very hard. Floods that wash its surface scarcely erode it, and its 

pebbles will roll for great distances in the streams. Its thickness 

varies from a few inches to several feet. It has a fairly even surface, 

conforming in a general way to the trend of the valley bottoms. Where 

a comparatively small amount of sand lies over it there are pools of 

standing water, as among the sand hills of the river bottoms. A like 

deposit is accompanied by similar phenomena in the Arkansas Valley 

of southwest Kansas.

River alluvium; sand dunes. The recent alluvium of the rivers not 

that now being deposited on their flood-plains is in many parts very 

thick, in some places exceeding 20 feet. It is cut everywhere into 

steep, often vertical banks, and is marked by stripes of black humus 

showing the various levels at which, as a flood-plain, it supported vegetation till covered by a new deposit from the overflowing waters of 

the river. The thickness of the deposit shows the great length of time 

during which the present conditions have existed, but there is no 

standard by which this can be measured in years. In places it rests 

on the loess, in others on the gumbo,.and in a very few on the rocks 

or shales of the region. At its bottom in many places is the gravel 

formed of the debris of the Tertiary conglomerate of the West. The 

alluvium itself is mostly a fine-grained sand of quartz particles, minute 

and round, with argillaceous and calcareous cement formed from the 

degradation of the Cretaceous and Tertiary formations of the West. 

When exposed to the winds it is blown into dunes, but owing to the 

rapidity with which vegetation takes hold, there are few areas of naked 

sand.

Baselevels. The Smoky Hill Eiver is cutting into the bottom of its 

bed at one or two points only. At no place in this region is either the 

Republican or the Kansas making its channel deeper. The rivers have 

reached a baselevel of operations and are now-cutting only laterally. 

The bottoms have distinct benches, but the highest are formed of the 

gumbo and the loess, though occasionally there is alluvium on them.
U. S. GEOLOGICAL SURVEY 

RED BLUFFS (.LOESS), SMOKY HILL RIVER, SOUTH BY EAST 
HAT.] CLIMATE. 29

CLIMATIC CHANGES.

From the statements already made as to the position of the loess at 

the bottom of the great valley and of the small ravines, it follows that 

these valleys, both large and small, were eroded ont to more than their 

present depth before the Glacial epoch. It would appear, then, that 

since the withdrawal of the glacial waters by elevation of the land the 

precipitation of the region has not been sufficient, with the elevation, 

to wash out the glacial deposits. Again, there are numerous ravines 

in this region not more, some less, than a quarter of a mile wide and 

nearly 200 feet deep, and abruptly terminating with a length of from 

half a mile to 2 miles. This would point to a period of climatic conditions different from the present perhaps not a long one in which precipitation was much greater and the erosive forces were much stronger 

than now. This period was pre-Glacial, Was it also mid-Tertiary, or 

pre-Tertiary, or both 1? The single fragment of Miocene grit seen in the 

Smoky Hill Yalley would suggest that to the depth at which, it lay 

within 30 or 35 feet of the very bottom of the erosion the great valleys 

had previous to that age been cut out; that is, that more than threefourths of the erosion was cut out in pre-Miocene time. Or, if the 

conditions of the grit as a littoral deposit connected with the Rocky 

Mountain uplift made this eastern part of it contemporary with later 

Tertiary time, still the erosion before must have been down to this depth.

From the present evidence it is not possible to say whether all the 

side ravines and creek valleys were eroded to the same depth at that 

time. Fragments of the Tertiary marl at no great distance suggest 

pre-Pliocene erosion, such as occurred in western Kansas. The absence 

of early Mesozoic formations and unconformity of the Dakota on the 

Penno-Carboniferous also suggest a pre-Oretaceous period of erosion. 

It might be, then, that, even with all these opportunites of the ages, 

the tooth "of time had gnawed but slowly into the solid body of the land 

until it reached its immediate pre-Glacial state. There is, however, 

an appearance about the ravines and creek valleys of this region that 

seems positively to indicate rapid erosion under conditions of great 

precipitation. We incline to the opinion, with some reserve, that the 

greater lines of erosion were cut mainly in the early Tertiary period, 

but that the erosive forces were at their maximum in the age immediately preceding the Glacial epoch, and that they were mainly attributable to two conditions decreasing temperature and increased 

precipitation.

The presence of much Dakota material in this western loess would 

indicate great erosion of those Cretaceous formations in the loessforming age; and the upper beds of the Permian mostly shales and 

soft limestones must have suffered much erosion in the same period 

and in that immediately preceding, the high prairie elevations being 

reduced rather than the valleys deepened. These remarks are partially
30 GEOLOGY OF FORT RILEY RESERVATION, KANSAS.

suggested by conditions prevailing outside the limits of the district 

under discussion, but the conditions within the region are all in consonance therewith.

CORRELATION OF DIFFERENT REGIONS.

Probably the most valuable part of this report is the definite identification of the various strata of the Fort Eiley section over the greater 

part of the area shown on the map. And with this must go the additional fact that the main features of the section, which may be cited 

as Nos. 5, 9, and 11 the Lower and Upper Flint beds and the Main 

ledge have been identified miles away, over the divide in the Feosho 

Valley. Whether there is a thickening or a thinning of these strata 

there, or of the intervening shales, has not been worked out, but with 

these landmarks plainly made out the way is open to complete correlation with the strata of the Neosho Valley and of its affluent, the 

Cottonwood. This work will therefore take its place as an integral part 

of the geology of Kansas.

ECONOMIC GEOLOGY.

SOILS.

The soils of the Fort Eiley district are a very important part of tho 

economics of the region. There are mainly two divisions of these soils 

as to position, viz, bottom soils and upland soils. These again are 

divisible each into subgroups as to structure and origin, thus:

Bottom soils................{ River alluvium.

I Lake silts: the gumbo and the loess.

Upland soils................ { Sedentary soils.

1 Lake silts: the loess.

Bottom soils. The river alluvium makes light, warm, sandy soils of 

great fertility, which even in bad years have yielded crops in all this 

region. Some farmers point to fields on these bottom lands that have 

never entirely failed of a crop during a quarter of a century of cultivation. The loess is not of great areal extent in the valleys, but it forms 

the subsoil of the higher benches and is the best of wheat land. These 

bottom soils are constantly being improved by the wash from the steep 

slopes above them, which adds both lime and silica to the soils below. 

In large parts of the bottoms the original transported soils have become 

changed by the prolonged growth of vegetation to a rich, black humus 

many feet deep. On the military reservation are four series of river 

bottoms and some creek bottoms that illustrate all these forms of soil, 

which, when under cultivation, will be the most fertile lands of the 

State, and which now yield the most luxuriant grasses, supplying 

abundant hay for the military post. The bottoms on the Smoky Hill 

and on the larger creeks are similarly situated, and under a constantly improving husbandry are showing increasing quantities of farm 

products.
HAT.] ECONOMIC GEOLOGY, 31

Upland soils. The upland soils may, in a certain sense, be all called 

sedentary; they have been formed on the spot and in many parts converted into a deep humus by the long-continued growth of vegetation. 

But the best and, as it fortunately happens, the most extensive soils 

of the upland are those of which the subsoil is the loess in its original 

or a modified form. It is a soil from the first. Plant life will flourish 

in it at once, so that where it has remained on the upland it gives a 

smooth surface on which, where undisturbed, the buffalo grass (Buchloe 

dactyloides) has kept longest hold, and where plowed it yields fine 

wheat. Orchards on these loess uplands thrive well. The rolling 

prairie has mostly the loess for its floor. There are, however, sedentary soils which are formed from the limestones and the shales of the 

district, where the loess has been eroded away. These soils, which are 

also locally called gumbo, are cold and somewhat intractable, and are 

mostly thin, occupying the flat tops of narrow ridges and promontories 

and the slopes to them. Grasses usually grow well on them, but they 

succumb soon to the influence of dry weather. In some places, however, these soils have become several feet thick and .are fairly productive. Cultivation, especially subsoiling, may aid in removing the 

principal defect of these soils thinness by facilitating the influences 

of meteoric agencies 'on their lower parts. Fortunately, these less valuable soils occupy but a small part of the tillable area of the soils of 

Geary, Eiley, and neighboring counties.

BUILDING MATERIALS.

Brick clays. The Quaternary deposits contain good materials for 

brickmaking. Bricks are in demand, and this demand has in past 

years somewhat encouraged a carelessness in western brickmaking 

that has perhaps not yet passed away, and the poor quality of bricks 

made has been wrongfully attributed to the clays used. The loess 

near Junction City is now yielding clay for a pressed brick which is of 

superfine quality, and the makers appear desirous to achieve the best 

possible results, which, so far, are satisfactory. As the true loess does 

not extend much farther west, the fine color of these bricks seems to 

insure a market for them all through western Kansas and Colorado. 

On the military reservation there is abundant loess, apparently of 

both Glacial epochs. Experiment would determine which is the better 

for brickmaking, but it is certain that both are good. The joint clay 

(gumbo) would also make good bricks.

Building stone. The so-called magnesian limestones of this district 

the Main ledge and the ledges above it are all useful for building purposes. They can be sawed and otherwise easily cut by the mason, and 

they harden on their exposed surfaces. The layers above the Main 

ledge, giving range stone from 6 to 24 inches in thickness, are mostly 

used, the Main ledge itself being used only where blocks of large 

cubical dimensions are wanted. The new buildings at Port Eiley
32 GEOLOGY OF FOET RILEY RESERVATION, KANSAS.

(see PI. YIII) show the character of these stones, as do also numerous 

private dwellings in Junction City and the surrounding region. The 

mid-Shale bed (No. 7) is also of fine quality in many parts of the district. 

At Fort liiley it is 3 feet thick; is known as the u white ledge," and is 

used for caps and sills. On Clarks Creek, at the mouth of Dry Creek, it 

is still thicker, and of fine quality. East of the district it is also of value, 

and beds lower than the numbered section are extensively quarried. 

The building stone of this district must, as population increases, be 

largely exported to the western part of the State as well as to the East. 

' Lime. The beds used for building stone are not good for the lime 

burner. The ledges of the flint beds are, however, better. This is 

especially true of the Lower Flints (No. 5), which give a very good quality of lime. They crop out on Three Mile Creek, on the military reservation, in positions easily available for quarrying, and also at various 

points on Clarks Creek and on the uplands to the southeast. They are 

also well developed near the mouth of Lyons Creek, where, at Wreford, 

lime-burning is carried on, the product being sent all over the district, 

and beyond. If another name were required for these strata we might 

call the Lower Flint beds the Wreford limestone. These beds are, however, more extensively used for the same purpose in the Neosho Valley, 

and for a general designation some other geographic term would perhaps be more appropriate.

Cement. Some of the ledges embedded in the shales have hydraulic 

properties, and some of the beds above the Main ledge have been worked 

for the purpose of making cement. This has been done at Milford, on 

the Eepublican Eiver, but the experiment has not been continued, nor 

perhaps thoroughly tried, though some of the material sent to Wyaiidotte County was for a time used successfully when combined with the 

cement rock of that region.

WATER SUPPLY.

Springs and wells. There are numerous springs in this region, but 

none above the Main ledge. A few that come out just under the Main 

ledge do not last long in a dry season. The Upper Flint ledges yield 

copious springs of perennial flow. Some of them are simply inexhaustible, and have scarcely diminished their flow in the driest years. Nearly 

all of them testify to the prevalent westerly dip of the strata. They 

come out on the west or northwest side of bluffs and hills. There are 

some springs on the military reservation which, though mostly constant, are not copious, owing to the small areas of the promontories 

and ridges but of which they come. Among the copious springs of the 

region is Barefield Spring, northwest from Junction City, which the 

writer measured at a time of its probable average flow, and found it to 

yield 110,000 gallons per day. The Seven Springs, in the Smoky Hill 

Valley, about 7 miles from Junction City, yield not less than 150,000 

gallons per day. .The flow at Spring Creek, 5 miles west of Skiddy, is
OST, FORT RILEY, CONSTRUCTED OF THE MAGNESIAN LIMESTONE OF THE DISTRICT.
HAY.] PALEONTOLOGY, 3

perhaps the largest in the region, as, coming straight from the earth, 

it drives a 16-foot overshot water wheel. In the neighborhood of each 

of these springs there is a group having smaller flow, and there are 

others elsewhere in this region. Of course these springs have "hard" 

water, but it is mostly free from organic matter. The alluvium of the 

river bottoms is a water holder, and the wells thereon are easily made 

and well supplied. The water is softer than that from springs or wells 

in the Carboniferous rocks. The gravel of Tertiary materials in which 

the wells of the military post find their source is probably of considerable extent in the three river valleys, and will insure large supplies 

of water, good for all domestic purposes.

Near the eastern boundary of Geary County, in Wabaunsee, there 

are flowing wells artesian of highly mineralized water. It is the 

same at Wainego and elsewhere down the Kansas Valley. The geology 

of eastern Kansas gives no explanation of the artesian flow of these

wells, but the occurrence of natural gas, and the known fact that in one 

or two instances the gas pressure raises the water to the surface, seem 

to suggest this as the reason of the artesian flow in the Kansas Valley. 

Wells on the upland usually obtain water in the horizon of the springs, 

viz, the Flint beds, and in the creek valleys beds of gravel under the 

alluvium yield large supplies.

Measurement of rivers. The rivers themselves are, of course, an inexhaustible source of water supply to the municipal and military populations on their banks. The water of the three rivers has not been 

continuously measured anywhere, but single measurements in the district have given the following figures:

Smoky Hill, June 15, 1891...... ....................

Kansas at Fort Eiley, June 18, 1891 ................

Cubic feet 

per secoTid.

2,045

OKI

6,961

PALEONTOLOGY.

It may be possible to supplement this report with a complete list of 

the Paleozoic fossils of the district, but in the absence of such list the 

names of the fossils occurring in the stratigraphic scheme of the Fort 

Eiley section will be of use. It would take comparatively little work 

to complete the survey of the Permian strata to the west and north, to 

their contact with the Dakota, and to give the fossils in their highest 

beds. For this the Fort Eiley section will be a valuable starting point.

It may be noted that trilobites (Phillipsia) have been found in the 

Main ledge, and this is probably the horizon of their highest occurrence. It has already been stated that the Productidae disappear at 

Bull. 137 3
34 GEOLOGY OF FORT RILEY RESERVATION, KANSAS.

the same horizon. Some of the Quarry ledges have abundance of 

Pecten and other lamellibranchs which seem to be persistent over great 

areas. Nautiloid shells are also found, especially in the higher beds. 

One was found in the mid-Shale bed (No. 7), but the others are all above 

No. 11. Four are new species, and as the horizon of one of them is 

apparently limited in vertical extent, it might perhaps give name to No. 

12 of the section, which might be called the Stenopoceras beds, from 

Stenopoceras (Phacoceras) dumbli Hyatt, the type specimen of which 

was obtained in the Fort Kiley quarries. Other specimens of this form 

have been since obtained at Junction City. The numerous Pecten and 

Pleurophorus casts might, however, suggest their names for the same 

beds.

The Quaternary deposits of this district seem almost entirely destitute of fossils. At Manhattan some years ago fragments of Elephas 1 

were found under 35 feet of loess. In the same neighborhood a loess 

nodule gave the teeth of a rodent. Farther down the Kansas Valley 

Professor St. John has found fragments of fish, but the beds of this 

region are singularly destitute of fossils. That there should be* no 

land fauna is suggested by the fact that the greatest elevations are 

surmounted by a sheet of loess. That the waters should have few or 

no remains of the fauna of temperate regions is understood, because 

those waters were cold, and the cold had come on only by secular modifications of preexisting conditions. If further research should demonstrate that the loess is absolutely unfossiliferous having no arctic or 

subarctic fauna the reason is probably because the great continental 

ice-sheet lay between this region and the arctic waters, and the currents along the ice-front were southerly and easterly in direction.

1A tusk 10 feet 6 inches long, another 9 feet 10 inches, a tooth 15 by 8J by 4J inches, and fragmenta 

of other teeth.
INDEX.

Alluvium.................................. 27-28

Baselevels.................................. 28

Biographic note on the author, deceased.... 11

Bowlders................................... 25

Brick clays................................. 31

Building materials......................... 31-32

Carboniferous strata....................... 17,20

Cement .................................... 32

Clays for brickmaking..................... 31

Climatic changes........................... 29

Correlation of different regions ............ 30

Creek valleys .............................. 13

Cretaceous geology of the district......... 23-24

Dakota deposits............................ 23

Deposition, littoral and shallow-water conditions of................................. 21-22

Dunes, sand................................. 28

Economic geology.......................... 30-33

Erosions, pre-Quaternary................... 22,29

Fenestella.................................. 21

Mint beds.................................. 17,19

Fort Kiley section.......................... 17-18

Fossils..................................... 21

Glacial deposits......................... 24-25,29

Grooves in limestone....................... 25-26

Gumbo..................................... 27-28

Gypsum.................................... 21,22

Hardpan................................... 28

Hemipronites, finding of, in the strata...... 21

Hill, R.T., remarks by..................... 11

Joint clay.................................. 28

Kansas-^Neosho -watershed.................. 14-15

Lime........................................ 32

Littoral conditions of deposition........... 21-22

Loess bluffs on the Republican River ...... 14

Loess of two periods....................... 26

Main ledge.............................. 17,18-19

Miocene grit in Smoky Hill Valley.........

Moraines...................................

Neosho-Kansas watershed..................

N"eosho Valley...................:..........

Paleontology of the district................

Paleozoic geology of the district...........

Pecten...............----. .................

Permian strata.............................

Permo-Carboniferous strata................

Phillipsia, finding of.......................

Pleurophorus ..............................

Producti, finding of, in the strata..........

Prosser, C. S., reference to work of, in 

Kansas...................................

Quarry beds................................

Quaternary geology of the district.........

Republican River, loess bluffs on the ......

Republican Valley..........................

River system of the district...............

Rivers,' measurement of....................

Sand dunes.................................

Section at Fort Riley ......................

Sink-holes ........................... 15-16,

Shales......................................

Shale (mid-) bed...........................

Smoky Hill Valley.........................

Soils .......................................

Springs and wells..........................

Stenopceras (Phacoceras) dumbli Hyatt... 

Stone for building purposes................

Synocladia.................................

Tertiary geology of the district............

Topography of the district.................

Trilobites, finding of.......................

Uplifts, continental........................

Water supply..............................

"Wells and springs..........i..............

35

29

24-25 

14-15

16

33-34 

16-23 

21, 34

17.20

17.21

33

21,34

21

11 

19

24-29 

14 

12 

12 

33 

28

17-18 

26-27 

17,20 

17,20 

13

30-31

32-33

34

31-32 

21 

24

11-16 

33

22-23

32

32-33