GEOLOGICAL SURVEY CIRCULAR 68 

June 1950 

DETAILED SECTIONS 

OF PRE-PENNSYLVANIAN ROCKS 

ALONG THE .FRONT RANGE OF COLORADO 

By 

John C. Maher 
UNITED STATES DEPARTMENT OF THE INTERIOR 

Oscar L. Chapman, Secretary 

GEOLOGICAL SURVEY 

W. E. Wrather, Director 

WASHINGTON, D. C~ 

Free on application to the Director, Geological Survey, Washington 25, .D. C. 
CONTENTS 

Page 

Introduction. . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . 1 

Section A. Beulah, Pueblo County, 

Colorado................................. 2 

Beulah limestone. . . . • . . . . . . . • . • . . . . . • . . . . 2 

Hardscrabble limestone................... 2 

Williams Canyon limestone................ 2 

Fremont limestone........................ 3 

Harding sandstone. . . . . . . . • . . . . . . • . . .. • . • • . 3 

Section B. South Hardscrabble Creek, Custer 

County, Colorado......................... 3 

Beulah limestone. . . . . . . • • . . • . • . • • . • • . • • • . 3 

Hardscrabble limestone. . • . . . • • • • • • . • • . . . • 3 

Williams. Canyon limestone·. . . . . • . • • • . • . . . • 4 

Fremont limestone ....•.....•.•.•.. :...... 4 

Harding sandstone........................ 5 

Section C. Specimen Hill, Fremont County, 

Colorado................................. 5 

Fremont limestone........................ 5 

Harding sandstone. • . • . • . . • • . . • • . . . • . • • . . • • 5 

Section D. Canon City, Fremont Cotinty, 

Colorado................................. 6 

Fountain formation. . . . . . . • . • . . • • • . . . • . . . • . 6 

Williams Canyon limestone................ 6 

Fremont limestone........................ 6 

Harding sandstone........................ 8 

Manitou limestone........................ 9 

Section F. South Tunnel, Phantom Canyon, 

Fremont County, Colorado ....... ·.••..•••.• 9 

Fremont limestone ......•.....•..•...•.••• · 9 

Harding sandstone. . . . . . . . . . . . . . . . . . • • • . • . 9 

Manitou limestone •........ .-. . . . . . . . • • • . . • 10 

Section F -1. Quarry, Phantom Canyon, 

Fremont County, Colorado................ 10 

Harding sandstone........................ 10 

Manitou limestone .....•...•...•.•...•.... 

Section F-2, Cemetery Park, Fremont 

County, Colorado ......•............•..... 

Fremont limestone ...•......•.•.•........ 

Section E. Oil Creek, Fremont County, 

Colorado •.•..•....•.............••...... 

Williams Canyon limestone ••..•••.•••.••.. 

Fremont limestone •...••..•.•••••...•.••. 

Harding sandstone ..•.•..•••••.•.••••..•.• 

Manitou limestone ........................ . Section G. Deadmans Canyon, El Paso 

County, Colorado ...••.•........•.....•.•• 

Harding sandstone ..•.....•..•.•••.•..•.•. 

Manitou limestone •.••..•....•. , ..•.•.•... 

Section H. Williams Canyon, El Paso 

County, Colorado ......•.•.••..•...••.••.. 

Hardscrabble limestone .•.•...•.......•.•. 

Williams Canyon limestone •..•...•..•...•• 

Manitou limestone, restricted •.....•....... 

Ute Pass dolomite ••....•••..•.•••...•..•. 

Sawatch quartzite ..••.•••..•.•.••••....... Section I. Missouri Gulch, Douglas County, 

Colorado •......•.••.....•.•.•...•...•... 

Hardscrabble limestone .......•.•.•....•.. Williams Canyon limestone ........•..•...• 

Manitou limestone •.••••..••.•.••..•..••.. 

Ute Pass dolomite ..•.••••.•.••.•........• 

Sawatch quartzite •.....•.•...•..•.•.•..... 

Section J. Grove Canyon, Douglas County, 

Colorado ...•..•..•.•.•.•.•....•••...•.•. 

Williams Canyon limestone ••.••.•.•.••.••• 

Ute Pass dolomite .••..•..•.•..•..•.•..•.. 

Sawatch quartzite .•.••.•••••••..••.••..•.. 

Literature Cited •..••••.••.•.•.•...••.•..... 

Page 

11 

11 

11 

11 

11 

12 

12 

13 

13 

13 

14 

14 

14 

15 

15 

16 

16 

17 

17 

17 

17 

18 

18 

19 

19 

19 

19 

20 

Locations of sections of pre-Pennsylvanian rocks along the Front Range of Colorado .................. facing p. 1 

Table 1. Past and present classification of pre-Pennsylvanian rocks along the Front Range of 

Colorado, and correlation with subsurface formations in western Kansas .............•.....•................ 1 
L A s I E L 8 E R T 

I 

_____ L ____________ _ 

p 

10 0 

0 

Colorado 

Springs 

E L 

u 

0 

10 

p A s 0 

Pueblo 

E 8 L 0 

20MILES 

LOCATIONS OF SECTIONS OF PRE-PENNSYLVANIAN 

ROCKS ALONG THE FRONT RANGE OF COLORADO 

I 

I 

I 

I 

I 

I 
Detailed sections of pre-Pennsylvanian rocks along the Front Range of Colon.do 

by 

._John C~-· Maher 

Since 1943, the U. S. Geological Survey, partly in cooperation with the State Geological Survey of Kansas, has 

been conducting detailed microscopic studies of the stratigraphy of the rocks penetrated in deep wells in western 

Kansas and eastern Colorado. The results of these studies have been released in a series of cross sections published by the State Geological Survey of Kansas (Collins, J. B._,1947; Edson, F. C.,1945, 1947; Maher, J. C., 1946, 

1947, 1948) and in a Preliminary Map of the Oil and Gas Investigations Series of the U. S. Geological Survey (Maher, 

J. C., and Collins, J. B., 1949). The subsurface studies necessarily have been based on correlation from well to 

well of suites of cuttings, supplemented by electrical logs. Standard subsurface practice of petroleum geologists in 

the Midcontinent region is to use the terminology of rocks exposed in the Mississippi Valley sections and in Oklahoma. 

As a logical part of the present investigation it was decided to trace the subsurface units westward to their outcrop 

in the Front Range in Colorado. 

Accordingly 12 sections of pre-Pennsylvanian Paleozoi_c rocks were measured and sampled along the Front Range 

at the places shown on the accompanying index map. The writer was assisted in this work by Donald C. Swanson in 

June, July, and August 1948. Measurements were made with a steel tape and Abney level, and sampling was done 

with a ·sledge, shovel, and mattock-pick. In the field, the samples were examined under a hand lens, tested with 

8N acid, and described in a notebook pefore being sacked in canvas bags. In the laboratory, these samples were crushed in a small ore crusher to the size of oil-well cuttings, washed, divided into three portions, sacked in paper 

sample ·.envelopes,· and filed in cardboard sample,_boxes-:- This procedure resulted in three complete sets of samples 

for each measured section. One set was examined under a low-power binocular microscope and described, one was used for preparations of insoluble residues, and one was placed in reserve. A description of the samples and residues for each section was made on a log strip using a scale of one inch to 10 feet in order to record the detail. This 

description was combined with data from the field notebook to give the sections described below. Fossils of the 

collections made were identified by G. A. Cooper of the United States National Museum. 

The correlations of the subsurface units with the rocks cropping out in the Front Range are shown graphically in 

Preliminary Chart 39 of the United States Geological Survey's Oil and Gas Investigations series (Maher, John C., 

1950). The correlation and nomenclature of the rocks also are discussed on the chart. The space available on the 

chart, however, does not permit the detailed description of individual rock units needed by subsurface investigators. 

It is believed that the fOllowing completely detailed description of the surface sections will be valuable to those who are doing subsurface stratigraphy based on the detailed examination of well cuttings. 

Table 1. Past arid present classification ·of pre-Pennsylvanian rocks along the Front 

Range of Colorado, and correlation with subs~face formations in western Kansas .. 

Previous classification .Y 1 Present classification 

Madison (or Leadville ~/ Beulah limestone· 

limestone MIDDLE(?) Hardscrabble limestone :MISSISSIPPIAN 

MISSISSIPPIAN Williams Canyon limestone 

LOWER 

MISSISSIPPIAN 

DEVONIAN Williams Canyon limestone DEVONIAN 

Fremont limestone Fremont limestone 

ORDOVJ:CIAN Harding sandstone ORDOVICIAN Harding sandstone 

Manitou limestone Manitou limestone (restricted) 

CAMBRIAN UPPER CAMBRIAN ( ?) Ute Pass dolomite 

Sa watch sandstone 1 UPPER CAMBRIAN Sawatch quartzite 

.Y Brainerd, A. E., Baldwin, H. L., Jr., and Keyte, I. A., Pre-Pennsylvanian 

stratigraphy of Front Range in Colorado: Am. Assoc. Petroleum Geologists Bull. vol. 17, no. 4, pp, 375-396, 1933. 

2/ Brainerd, A. £., and Johnson, J. H., Mississippian of Colorado: Am. Assoc. 'r>etroleum Geologists Bull., vel. 18, no. 4, pp. 541-542, 1934. 

~/ Includes some Upper Cambrian in the type area. 

- 1 -

SUbsurface classification 

in 

eastern Colorado and western Kansas 

Ste. Genevieve limestone· 

MIDDLE St. Louis limestone MISSISSIPPIAN 

Spergen limestone 

Warsaw limestone 

LOWER Osage group MISSISSIPPIAN 

Kinderhook group 

DEVONIAN 

Viola limestone 

ORDOVICIAN Simpson group 

Arbuckle group ~/ 

Bonneterre dolomite UPPER CAMBRIAN Lamotte sandstone 
SECTION A. Belliah, Pueblo County; Colorado, NWt and NEt sec. 4, T. 23 S., 

R. 68 W., and SEt sec. 32, T. 22 S., R. 68 W. 

(~easured by hand level and tape along cliffs on north side of Middle cree~. ) 

Carboniferous 

Pennsylvanian rocks 

Fountain formation 

Mississippian rocks 

Beulah limestone 

(Measurements in the NWt sec. 4, T. 23 S., R. 68 W.) 

Limestone, red-stained buff fine sandy with red-stained buff calcareous,fine-grained· 

sandstone layers and yellow-mottled red dense chert at top-------------------------------

Limestone, yellowish .. buff, very oolitic, slightly sandY-------------------------------------

Sandstone, yellow, very limy, very fine, grading downward into pink-tinged buff oolitic 

medium-crystalline limestone. Oolites are oblong in part--------------------------------

Limestone, yellowish-buff, finely oolitic--------.------------------------------------------

Limestone, buff, finely crystalline to dense, containing red-mottled gray-buff dense chert-----

Limestone, platy, buff, shaly------------~-----------------------------------------------

Limestone, reddish buff, fine sandy, finely oolitic-----------------------------------------

Limestone, gray buff, very oolitic, medium crystalline, grading downward into red to 

yellow finely oolitic finely crystalline limestone-----------------------------------------

Limestone, finely red-banded, yellowish buff, finely oolitic, finely crystalline----------------

Limestone, red- and yellow-mottled buff, faintly oolitic, finely crystalline-------------------

Limes~one,. re~ to yellowish bu;ff, oolitic, slightly sandy. Oolites range from fine to . 

medium In SIZe-----------------------------------------------------------------------

Limestone, cream-colored, very oolitic. Oolites are fine to medium in size----------------

Limestone, gray buff,- very oolitic, finely crystalline to dense-------------------------------

Sandstone, yellow to white, calcareous, medium- to coarse-grained, might be cave-fill-------

Total thickness of Beulah limestone----------------------------------------------------

Hardscrabble limestone 

Limestone, gray, finely oolitic, finely crystalline, and gray dense limestone containing 

a trace of orange dense chert----------------------------------------------------------

Limestone, gray, finely oolitic, finely crystalline to dense---------------------------------

Limestone, rubbly, graybuff, dense---------~------------------------------------------­

Covered interval from base of upper cliff to top of lower cliff-------------------------------

(Measurements near Indian Cave in the SEt sec. 32, T. 22 S., R. 68 W~) 

Limestone, dark-buff to brown, finely crystalline to dense. Top of lower cliff----------------

Limestone, slightly pink-tinged cream-colored, finely crystalline to dense-------------------

Limestone, slightly pink-tinged, fossiliferous, finely crystalline to dense, containing 

sm8fl brachiopods--------------------------------------------------------------------

Limestone, cream-colored to buff, finely crystalline to dense-------------------------------

Limestone, purple-mottled buff to dark-buff, dense----------------------------------------

Limestone, pink-mottled buff, chalky, very fine sandy-------------------------------------

Limestone, buff, medium crystalline, grading downward into soft pink-mottled gray 

finely crystalline limestone containing pebbles of reworked Williams Canyon 

limestone. Distinctly irregular basal surface------------------------·-------------------

Total thickness of Hardscrabble limestone-----------------------------------------------

Williams Canyon limestone 

Limestone, yellow, coarsely crystalline--------------------------------------------------

Dolomite, hard, purple-mottled lavender, very finely granular~ with conchoidal fracture-------

Sandstone, red, yellow, and gray, 'limy, fine-grained, and purple- and maroon mottled 

gray finely crystalline limestone-----------------------------------------------·--------

Dolomite, lavender to gray, finely granular, containing one layer of pinkish -white finely 

granular to dense chert nodules. Upper 2 feet weathers bright yellow----------------------

Dolomite, lavender to purple, finely crystalline, and dolomitic limestone with thin 

veins of calcite-----------------------------------------------------------------------

Covered interval. Contact with Fremont limestone not exposed------------------------------

Total thickness of Williams Canyon limestone--------------------------------------------

- 2 -

Ft. in. 

5 6 

l 

4 6 

3 

8 

l 

10 

5 6 

5 6 

5 6 

5 6 

5 6 

5 6 

3 6 

53 0 

4 6 

5 6 

5 6 

38 

5 6 

27 6 

5 6 

16 6 

g 6 

I 6 

5 6 

125 0 

1 

3 

3 

5 6 

4 3 

1 3 

16 3 
Ordovician rocks Ft. · in. 

Fremont limestone 

Dolomite~ pinkish buff, finely to coarsely crystalline-------------------.;.-------------------- 5 

Dolomite, pinkish buff to red, finely to coarsely crystalline, with thin beds of brick-rf3d 

finely granular dolomite------------------------------------------------------------------ 5 

Dolomite, massive, pitted, pink to red, coarsely crystalline--------------------------------- 5 8 

Contact of Fremont limestone and Harding sandstone is not exposed but estimated to be 

within 3. feet of bed described above------------------------------------------------------ 3 

Total thickness of Fremont limestone---------------------------------------------------- 18 8 

Harding sandstone 

(Measurements in the NEt sec. 4, T. 23 S., R. 68 W.) 

Covered interval which, judging by incomplete exposures and float, includes hard, purple 

and green, limy, f~ne-grained sandstone at top and purple, red, and green sandy shale 

at bottom----------------------------------------------------------------------------- 16 8 

Sandstone, medium-bedded, white, very·fine grained---------------------------------:------- 4 

Sandstone, thin-bedded, white to pink, limy, very fine grained-------------------------------- 11 

Covered interval, in part purple and red shale--:..------------------------------------------- 22 6 

Shale, red to brown, fissile; green very fine grained sandstone, and green-spotted red 

to purple waxy shale-------------------------------------------------------------------- 3 

Sandstone, green, very fine grained, and maroon, green, and purple waxy shale---------------- 3 6 

Sandstone, thin-bedded, white, very fine grained, with two hard quarttitic layers about 

6 inches thick. This unit forms a distinct ledge------------------------------------------- 4 6 

Sandstone, pale-green, limy, very fine grained---------------------------------------------- 2 

Sandstone, purple-mottled and green-spotted white, limy, very fine grained-------------------- 4 6 

Sandstone, pink-mottled white, limy, very fine grained, with large white quartz 

boulders at base------------------------------------------------------------------------ 5 

Total thickness of Harding sandstone-----------------------------------------------------76 6 

Pre-Cambrian granite 

SECTION B. South Hardscrabble Creek, Custer County, Colorado, St sec. ll, 

T. 22 S. , R. 89 W. 

[The beds here stand nearly vertical (dip 82° SWJ as a result of faulting. Several faults cut the section, one of 

which traverses the Williams Canyon limestone beds. The section was measured by tape where undisturbed by 

faults.] 

carboniferous 

Pennsylvanian rocks 

Fountain formation 

Mississippian rocks 

Beulah. limestone 

Upper' few feet not exposed. 

Limestone, massive, pinkish red, very sandy------------------------------------------------ 5 

Chert, red to yellowish buff, pyritic, dense------------------------------------------------- 4 

Limestone, buff, dense-------------------------------------------------------------------- 1 8 

Limestone, pink- and white-mottled, finely oolitic------------------------------------------- 1 

Limestone, thin-bedded, pink- and white-mottled, finely oolitic, fine sandy--------------------- 1 

Limestone, red, finely crystalline; red fine sandy limestone; and buff finely oolitic fine sandy 

limestone------------------------------------------------------------------------------ 5 

Limestone, medium-bedded, buff-mottled red; fine sandy, finely crystalline, containing 

scattered calcite crystals------------------------------------------------------_ _.-------- 8 8 

Limestone, massive, compact, tan, slightly oolitic, finely crystalline, and white to pink finely 

oolitic fine sandy limestone-------------------------------------------------------------- 5 

Limestone, massive, compact, pfnk, finely oolitic, fine sandy, grading downward into white 

finely oolitic, finely to medium-crystalline limestone----------------------------'----------- 3 6 

Limestone, white, finely oolitic, finely to medium-crystalline, and pink finely oolitic fine 

sandy limestone------------------------------------------------------------------------- 5 

Limestone, red to buff finely crystalline, with white calcite veins, red chalcedonic chert, and 

purple fine sandy chert------------------------------------------------------------------ 4 8 

Total thickness of Beulah limestone-------------------------------------------------------W 6 

Hardscrabble limestone 

Limest0ne, pink to white, coarsely oolitic, with purple- and gray-mottled fine sandy chert showing faint figurE:s. Oolites are large and oblong. The top of this bed is very irregular, suggesting a slight unconformity---------------:-3

-_----------------------------------------- 1 6 
Chert, brown to purple, faintly figured, fine sandy to dense------------------------------

Limestone, gray, finely crystalline, and red very oolitic finely to medium-crystalline 

limestone with irregular nodules of white to tan granular, to dense chert and red to · white calciteveins-------------------------------------------------~----------------

Limestone, gray, finely crystalline, ·with limestone pebbles and red and white calcite 

veins, and buff finely crystalline limestone containing traces of cream-colored dense chert---~--------------------------------------------------------------------------

Limestone, lavender to gray, finely crystalline, with tan dense chert grading downward into 

buff fine sandy limestone with white granular chert-------------------------------------

Limestone, lavender, finely crystalline to dense, with some layers of white fine sandy 

limestone-------------------------------------------------------------·--------J ___ _ 

Limestone, brown, finely crystalline to dense-:------------------------------------------

Limestone breccia, brown, dense, grading downward into brown dense limestone underlain 

by badly altered buff finely crystalline limestone and yellow-stained fine sandy limestone--

Limestone, buff to bro.wn, finely crystalline to dense, containing tan crinoidal dense chert------------------------------------~---------~-------------------------------

Dolomite, lavender- and purple-banded, buff, dense------------------------------------':"-

Limestone, red, finely crystalline-------------------------------------------------------

Limestone, cream-colored to buff, fine to coarsely crystalline, containing calcite and tan 

dense to granular chert-------------------------------------------------------------

Limestone, buff to dark buff, finely crystalline, containing limestone (?}pebbles, calcite, 

and white subtranslucentc~ert-------------------------------------------------------

Limestone, pinkish white, medium crystalline, and buff to brown dense to finely 

crystalline' limestone---------------------------------------------------------------

l,jimestone, red-mottled buff to brown, finely crystalline, and buff siliceous limestone-;. ____ _ 

Limestone, red-mottled buff, finely crystalline, cream-colored medium-crystalline 

limestone; and cream-colored dense chert--------------------------------------------

Limestone, cream-colored, finely crystalline to dense-----------------------------------

Chert, cream-colored, dense-----------------------~---------------------------------~ 

Limestone, buff, finely crystalline------;..-----.----------------·-------------------------

Limestone, buff, coarsely crystalline, with 1- to 2-inch layers of tan dense chert-----------

Limestone, buff, finely crystalline, with some pink very finely granular dolomite-----------

Limestone, buff to brown, dense, containing calcite veins and 1- to 2-inch layers of tan 

dense chert. This bed forms top of lower massive ledge-------------------------------· 

Limestone, buff to brown, finely crystalline------------------------------7"--------------

Limestone, buff, finely crystalline, containing brachiopods; white finely to mediumcrystalline limestone; and brown dense limestone-------------------------------------:-

Limestone, buff, finely crystalline, containing white calcite grading downward into pink 

finely granular dolomitic limestone----------------------------------------------------

Limestone, pinkish buff, fin~ly crystalline, with white calcite veins------------------------

Limestone, red-mottled brown, finely crystalline, with calcite veins---------------..:-------

Limestone conglomerate, red-stained, with wavy basal contact----------------------------

Total thickness of Hardscrabble limestone----·---------------------------------------

Williams Canyon limestone 

Limestpne, gray to brown, finely crystalline--------------------------------------------

Dolomite, platy, gray buff, finely granular to dense--------------------------------------

Limestone, pink, finely to medium crystalline-------------------------------------------

Sandstone, red-banded white, limy, fine- to medium-grained-----------------------------

Dolomite, purple-banded lavender'· finely crystalline, with included sand grains at top-------

Dolomite, platy, purple to lavender, very finely granular; purple coarsely crystalline 

limestone; and tan finely granular dolomite-.------------------------------------------

Limestone, purple to lavender, finely to medium crystalline, dolomitic, with small bed 

of tan finely granular dolomite at base--------.----------------------------------------

Limestone, lavender to purple, finely granular, dolomitic, buff dense limestone; and· 

purple finely crystalline limestone with calcite-----------------------------------------

Dolomite, red to lavender, finely granular------------------------------------------:----

Limestone, thin-bedded, purple, finely granular, dolomitic, grading downward into purple 

finely granular dolomite and purple fine sandy dolomite and dolomitic fine sandstone 

with wavy basal contact-------------------------------------------------------------

Total thickness of Williams Canyon limestone------------------------------------------

Ordovician rocks 

Fremont limestone 

Dolomite, red, finely granular to medium crystalline, yellow-stained in part---------------

Dolomite, red, finely to medium crystalline, containing small crinoids and calcite veins-----

Dolomite, red, finely to medium crystalline, with calcite veins and some yellow staining-----

Total thickness of Fremont limestone----------------.;..--------------------------------

-4-

Ft. 

T 

5 

3 

5 

6 

5 

5 

4 

1 

5 

10 

5 

5 

5 

3 

10 

2 

2 

3 

5 

g 

6 

5 

5 

4 

1'24 

1 

1 

2 

3 

5 

10 

5 

5 

8-

5 

10 

~ 

in. 

~ 

2 

6 

11 

1 

6 

g 

3 

2 

6 

3 

3 

2 
Harding: sandstone 

Sandstop.e, white to yellow, very fine qrained-------------------------------------7 -------

Covered interval-----------------------------------------------------------------------

Sandstone, white, pink, and red, limy, very fine qrained, with abundant fish scales----------

Shale, platy, red to purple, fine sandy---------------------------------------------------

Sandstone,. thin-bedded, white to pink, slightly limy, very fine qrained----------:..--------~--

Covered interval----------------------------------------------------·-------------------

Sandstone, thin-bedded, white to lavender, slightly limy, very fine grained------------------

Sandstone, thin-bedded, white to lavender, nonlimy, very fine grained----------------------

Sandstone, thin-bedded, pink-tinqed, nonlimy, very·fine qrained---..:-----------------------

Sandstone, white, nonlimy, medium -qrained ---------------------------------------------

Total thickness of Harding: sandstone---------------------------------------------------

Pre-Cambrian granite 

SECTION C. Specimen Hill, Fremont County, Colorado, SEt sec, 32, T. 19 S., 

R. 70 w~ 

(Measured by tape on west side of Oak Creek qrade road. Beds strike N. 14° W. and dip 

77° E.) 

Jurassic rocks 

. Morrison formation, 

Ordovician rocks 

Fremont limestone 

Ft. 

5 

10 

1 

5 

8 

41 

3 

5 

4 

85 

Covered interval, estimated------------------------------------------------------------ 5 

Dolomite, slightly orange-mottled buff, medium-crystalline, with traces of 

white opaline chert------------------------~------------------------------------------ 5 

Dolomite, soft, buff, finely qranular, resembles sandstone when weathered. 

Trace of oranqe chalcedonic chert------------------------------------------------------ 10 

Dolomite, buff, finely granular---------------------------------------------------------- 5 

Dolomite, hard, buff, finely crystalline, containing: small qeodes of bluish-white 

andoranqe aqatelike chert------------------------------------------------------------ 5 

Dolomite, buff, finely crystalline, with disseminated bluish-white opaline chert-------------- 5 

Dolomite, tan, medium-crystalline, containing: red ag:atelike chalcedony and white calcite----- 10 

Dolomite, buff to tan, finely to medium-crystalline, containing: some calcite and 

afewquartz qeodes------------------------------------------------------------------ 5 

Dolomite, pinkish tan, finely to medium-crystalline, with disseminated bluish-white opaline chert and calcite----- ___ ;.;. _____________________________________ ::_______________________ 5 

Dolomite, buff to tan, fine- to medium-qrained, with abundant quartz qeodes and calcite. 

Abundant qray-, red-, and tan-banded chalcedony--------------------------------------- 6 

Dolomite, pinkish buff, fossiliferous, medium-crystalline, containing: quartz qeod9s, 

crinoids, and brachiopods. A thin bed of white fine-qrained sandstone is present near theb~se----------:----------------------------------------------------------------- 4 

Dolomite, pinkish buff, very fossilife;rous, medium-crystalline, containing: abundant red to 

pink aqatelike chalcedony in g:eodes; Rece~taculites and Rhynchotrema arqenturbica. -------- 6 

Dolomite, yellow-stained, tan to brown, me ium to coarsely crystanine, with dissemmated 

bluish-white opaline chert and white calcite veins---------------------------------------- 4 

Dolomite, pinkish buff, coarsely crystalline, with thin veinlets of blue-white opalin9 chert----- 5 

Dolomite, pinkish-buff, coarsely crystalline, with abundant quartz g:eodes containing: red, 

yellow, and white aqatelike chalcedony and white mammillary chert----------------------- 5 

Dolomite, pinkish buff, coarsely crystalline, with thin veins of qray to tan dense chert-------- 4 

Dolomite, red, finely crystalline-------------------------------------------------------. 1 

Dolomite, red, fossiliferous, medium to coarsely crystalline, containing: cup corals 

in. 

7 

2 

10 

6 

5 

6 

6 

6 

(Favosites?) and abundant dense white to qray and tan subtranslucent chert---------------- 5 

Total thickness of Fremont limestone-------------------------------~------------.: _____ -go 0 

Harding: sandstone 

Shale, purple and yellow---------------------------------------------------------------- 4 4 

Sandstone, purplish pink, fine-qrained------------------------------------- -~- ----------- 1 Coveredinterval-------------------------------------------------------------------~--- 42 7 

Sandstone, hard, white, quartzitic, very fine qrained-------------------------------------- 3 4 

Covered interval. White fine-qrained sandstone, 1 foot thick, in middle of interval contains 

abundant fish plates------------------------------------------------------------------ 17 

Sandstone, hard, white, limy, very fine qrained------------------------------------------- 3 

Sandstone, bright yellow-stained white, limy, very fine grained---------------------------- 4 

Covered interval. Probably white fine-qrained sandstone----------------------------------- 15 - 5-
Ft. in. 

Sandstone, hard, white, quartzitic, fine-grained---------------------------------------:---- 1 

Total thickness of Harding sandstone--------------------------------------------------- gr- 3 

Pre-Cambrian granite 

SECTION D. Canon City, Fremont County, Colorado, sec. 13, T. 18 S., 

R. 71 W. (Priest Canyon), sec. 31, T. 18 S., R. 70 W. (Harding Quarry), 

and sec. 36, T. 17 S., R. 71 W. (Gnat Canyon). 

Carboniferous 

Pennsylvanian rocks 

Fountain formation 

(Measured by Abney level and tape along Priest Canyon road, 

sec. 13, T. 18 S., R. 71 W.) 

Sandstone, massive, red, arkosic, coarse-grained, containing limestone boulders and 

pebbles in base--------------------------------------------------·------------------- 49 

Shale, purplish maroon, micaceous, sandy, interbedded with white micaceous anQUlar fineto medium-grained sandstone---------------------------------------------------------- 4 6 

Sandstone, purplish white, micaceous, fine-grained---------------------------------------- 1 6 

Sandstone, purplish white, micaceous, angular, coarse-grained---------------------------- 1 

Sandstone, yellow to purple, fine-grained, and sandy shale with abundant l~monite concretion$ 

from size of bird shot to bean---------------------------------------------------------- 3 

Shale, hard, blocky, brick-red, iron-cemented, sandy, wlth a trace of reworked red chert---- 5 

Covered interval-----------------------------------------------------------------~----- 4 

Shale, crumbly, brick-red, sandy, with limonite concretions and reworked cream-colored 

granular chert concretions------------------------------------------------------------ 6 

Sandstone, white, well-sorted, subround, fine- to medium-grained, containing reworked 

buff dense chert concretions------------•----:------------------------------------------- 1 

Shale, crumbly, maroon, sandy, with fragments of leached dolomite and chert---------------- 6 

Sandstone, white, subround, fine- to medium-grained, and some pink quartzitic very fine grainedsandstone-------------------------~--------------------------~--------------- 5 

Sandstone, red-stained, gray white, subround, fine- to medium-grained--------------------- 3 

Shale, purple to red limy fine sandy, containing fragments of reworked cream-colored 

dense chert. Irregular basal surface--------------------------------------------------- 1 

Total thickness of Fountain formation-------------------------------------.:.-------------W 0 

Mississippian rocks 

Williams Canyon -limestone 

(Measured by Abney level and tape on north wall of creek in Priest Canyon, 

sec. 13, ~- 18 S., R. 71 W.) 

Dolomite, purple- and yellow-mottled cream-colored, very finely granular------------------- 2 

LimestQne, purple- and yellow-mottled gray, finely to medium crystalline, dolomitic, with 

10-inch bed of hard compact very finely granular dolomite in middle----------------------- 5 

Limestone, thin- and wavy-bedded, purple- and yellow-banded gray, finely crystalline, 

dolomitic, and pink medium crystalline limestone--------------------------.-------------- 5 

Dolomite, yellow-mottled gray, finely granular, with 6-inch bed of yellow-buff coarsely 

crystalline limestone in middle--------------------------------------------------------- 5 

Dolomite, thin- and wavy-bedded, purple- and yellow-mottled gray, very finely granular, 

and dolomitic limestone---------------------------------------------------------------- 5 

Dolomite, thin- and wavy-bedded, purple-mottled, gray, very finely granular, and red-yellow 

finely crystalline, containing scattered sand gr,ains, and angular limestone pebbles, 1 inch 

in diameter, in lower 3 feet------------------------------------------------------------ 4 9-

Shale, hard, maroon, sandy, containing anQUlar limestone pebbles. IrreQUlar basal surface---- 3 

Total thickness of Williams Canyon limestone-------------------------------------.:.------Wl 0 

Ordovician rocks 

Fremont limestone 

(Measured by Abney level and tape along road and creek in Priest Canyon, sec. 13, T. 18 S., R. 71 W.) 

Dolcmite, thin-bedded, purple-mottled buff, finely 9I"anular--------------------------------- 4 

Dolomite, purple-tinged buff, finely crystalline----.:---------------------,.----------------- 1 

Dolomite, hard, cream-colored, finely oolitic (?)or microfossiliferous (?), finely granular---- 1 

Dolomite, thin-bedded, cream-colored, finely granular--------':"-----------------------------3 

- 6 -
Ft. 

Dolomite, massive, slightly purple-mottled buff, finely to very finely granular, with few 

brachiopods near base. Forms distinct ledge------.:.----------------------------------- 19 

Dolomite, soft, pinkish buff, shaly, very finely granular--------------------------.,-------

Dolomite, hard, pink to buff, very fine+y granular, with few brachiopods-------------------- 1 

Dolomite, thin-bedded, slightly red-mottled gray white, very_finely granular------:---------- 2 

Dolomite, platy, pink-tinged gray white, limy, very finely granular--------- --------------- 3 

Dolomite, .thin-bedded, gray white, very finely granular----------------------------------- 2 

Dolomite, thin-bedded, gray buff, finely granular----------------------·------------------- 1 

Dolomite, thick-bedded, gray buff, slightly fossiliferous, very finely granular--------------- 4 

Dolomite, pink to gray buff, finely to very finely granular---------------------------------- 10-

Dolomite, pinkish gray, finely granular-------------------------------------------------- 1 

Dolomite, pink to white, very fine sandy, finely granular---------------------------------- 2 

Dolomite, purplish buff finely crystalline------------------------------------------------- 2 

Dolomite, purple-mottled buff, finely granular, with crinoids, brachiopods, and corals. 

Forms ledge------------------------------------------------------------------------ 10 

Shale, platy, purple d0lomitic, in part very fine sandy; platy, brown dolomitic shale---------- 5 

Dolomite, purple to cream-colored, finely crystalline':"---..:-------------------------------- 5 

Dolomite, slightly purple-tinged gray buff, fossiliferous, finely granular to finely 

crystalline, containing small calcite vugs. Receptaculites (?)---------------------------- 5 

Dolomite, slightly purple-tinged gray buff, finely crysta:Ihne to finely granular, with 

brachiopods in lower part. Forms ledge----------------------------------------------- 16 

Dolomite, pinkish gray, fossiliferous, finely crystalline to finely granular, with small 

calcite vugs. Brachiopods and gastropods---------------------------------------------- 10 

Dolomite, dark-buff, medium-crystalline------------------------------------------------- 5 

Dolomite, pink-tinged buff, finely to medium-crys~alline----------------------------------- 10 

Dolomite, pink-tinged buff gray, finely granular td finely crystalline------------------------ 6 

Dolomite, pinkish gray, fossiliferous, slightly liniy, finely granular to finely crystalline, 

containing some red-mottled buff dense chert. Gastropods------------------------------- 5 

Dolomite, compact, pinkish gray, finely banded, finely granular---------------------------- 5 

Dolomite, pink to gray, fossiliferous, finely_ granlJ].ar, containing a few gastropods----------- 5 

Dolomite, badly altered, pink-tinged buff, finely 1:9 medium crystalline--~------------------- 16 

Dolomite, gray buff, granular------------------•---------------------------------------- 1 

Dolomite, hard, slightly pink-tinged buff, finely to medium crystalline---------------------- 5 

Dolomite, buff, very porous, medium to coarsely crystalline------------------------------- 3 

Dolomite, purple-mottled gray, medium to coarse~y crystaliine---------------------------- 2 

Dolomite, slightly pink-tinged cream-colored, medium to coarsely crystalline--------------- 5 

Dolomite, hard, slightly pink-tinged. cream-colored, medium crystalline, containing tan_ 

dense chert nodules-------------------------~---------------------------------------- 6 

Dolomite, pinkish-gray, fossiliferous, granular to medium crystalline. Abundant brachiopods, sponges, and corals-------------------~·--------------------------------------- 5 

Dolomite, light-buff, fossiliferous, finely granular. Brachiopods and crinoids-------.:-------- 16 

Dolomite, massive, pinkish buff, fossiliferous, finely granular. Brachiopods in lower half---- 11 

Dolomite, gray, finely granular----------------..:----------------------------------------- 1 

Dolomite, compact, pink, finely crystalline to dense, with cone-in-cone structure------------

Dolomite, pink to buff, finely to medium crystalline--------------------------------------- 8 

Dolomite, dark-buff, finely crystalline----------------:----------------------------------- 6 

Dolomire, buff, sparsely fossiliferous, finely granular to finely crystalline, with a few 

brac-hiopods in lower part----------------------------------------.;.----------""·--------- 6 

Dolomite, cream-colored to buff, crinoidal, finely granular to finely crystalllne. Filled cave nearby in this bed------------------------------·---------------------..... .;.................. 5 

Dolomite, pinkish gray, fossiliferous, very finely granular, and pinkish-gray, finely to 

coarsely crystalline dolomite. Brachiopods-------------------------------------------- 6 

Dolomite, buff, fossiliferous, finely to medium crystalline. Abundant crinoids, brachiopods, 

gastropods, and Receptaculites(?}----------------------------------------------------- 5 

Dolomite, purple-mottled bUff, granular to medium crystalline----------------------------- 5 

Dolomite, pinkish buff, fossiliferous, finely to medium crystalline. Abundant crinoids and 

brachiopods------------------------------------------------------------------------- 6 

Dolomite, maroon-mottled buff, sparsely fossiliferous, granular to medium-crystalline. 

Crinoids. Upper 3 feet appears brecciated or pebbly------------------·------------------ 5 

Dolomite, pink to pinkish buff, fossiliferous, medium-crystalline, with brown resinous 

aragonite. Abundant crinoids, Receptaculites (?}, and Orthoceras-t'ype cephalopods-------- 5 

Dolomite, badly altered, pink to red, coarsely crystalline, wlth.red silt in interstices--------- 5 

Dolomite, badly altered, pink to red, medium to coarsely crystalline-----------~------------ 6 

Total thickness of Fremont limestone--------------------------------------------------:mT" 

- 7-

8 

4 
Harding sandstone 

(Measured with Brunton compass and tape at first hairpin curve on entrance 

road to Harding Quarry about center s. line NEtswt sec. 31, T. 18 S., 

R. 70 W., and on north wall of Harding Quarry about center south line 

NEtNWt sec. ·31, T. 18 S., R. 70 W.) 

Shale, pale-green and maroon, fossiliferous, waxy, purple, very fine sandy, and greenishFt. in. 

white very fine grained sandstone. Abundant fish plates--------------------------------- 4 

Sandstone, massive, bright-yellow, pink, purple, and white, fossiliferous, very fine grained. 

Abundant fish plates on upper surface--------------------------------------------------· 13 

Sandstone, white, limy, very fine grained----:-:-------------------------------------------- 4 

Sandstone, greenish white, limy, very fine grained, and pcrple very fine grained sandstone 

containing fish plates----------------------_:._----------------------------------------- 8 

Sandstone, greenish w:P.ite, limy, very fine grained---------------------------------------- 2 

Shale, hard, fissile to blocky, purple, fossiliferous. Fish .plates--------------------------- 2 6 

Sandstone, white to lavender, fossiliferous, very fine grained. Fish plates------------------ 1 7 

Sandstone, red, very fossiliferous, shaly, very fine grained. Fish plates------------------- 5 

Sandstone, massive, white- and pink-mottled, very fine grained. Fish plates at top---------- 12 6 

Sandstone, red and white, fossiliferous, very fine grained. Fish plates--------------------- 1 6 

Shale, pink, very fine sandy-----------------------------:.------------------------------- 1 6 

Sandstone, massive,. pink to red, very fine grained---------------------------------------- 5 

Sandstone, thin-bedded, pink to red, very fine grained------------------------------------- 3 6 

Sandstone, platy, white to pink, very fine grained----------------------------------------- 2 

Shale, pink, purple, and green, very fossiliferous. Abundant pelecypods, brachiopods, and 

fishplates-------------------------------------------------------------------------- 1 10 

Shale, hard, blocky, purple and green, sparsely fossiliferous, fine sandy. Brachiopods------ 8 

Shale, hard blocky brown, sparsely fossiliferous, very fine sandy. Fish plates-------------- 10 

Shale, brownish green, fossiliferous. Orange fish plates---------------------------------- 5 

Shale, brown, green, and purple, very fossiliferous, very finely banded. Orange fish plates-- 7 

Shale, blocky, green-spotted purple to br.own--------------------------------------------- 10 

Shale, fissile, brown, waxy, with thin layers of purple shale------------------------------- 5 10 

Shale, fissile, bright purple------------------------------------------------------------- 7 

Sandstone, purple- and gr~en-mottled white, very fine grained-----------------------------· 2 3 

Sandstone, white, fossiliferous, fine-grained. Fish plates and other fossils near base. 

Forms ledge-------------------------------·---------------------------------------- 4 11 

Shale, purple, fossiliferous, slightly limy, very fine sandy. Fish plates-------------------- 1 4 

Sandstone, slightly pink- and green-tinged white, very fine grained-------------------------' 8 8 

Shale, purple-mottled mustard-green, fossiliferous, very fine sandy. Fish plates, 

pelecypods, and gastropods----------------------------------------------------------- 3 2 

Shale, green, fossiliferous, with black inclusions and fish plates-----·---------------=------- 10 

Shale, red to purple, slightly fossiliferous, waxy----------------------------------------- 6 6 

Shale, slightly green-mottled brown, waxy----------------------------------------------- 2 

Shale, purple and green, fine sandy------------------------------------------------------ 6 

Limestone, green-mottled purple to red, very fine sandy, and very limy, very fine grained 

sand~tone--------------------------------------------------------------------------- 7 

Sandstone, red and brown, limy and shaly, very fine grained------------------------------- 5 

Shale, platy, chocolate brown, fossiliferous----------------------------------------'------ 3 

Shale, purple and green, fine sandy---------------------------------------:--------------- 8 

Limestone, red and purple, very fossiliferous, fine sandy. Abundant fish plates on upper 

surface-----------~----------------------------------------------------------------- 1 

Sandstone, pink to white, limy, very fine grained, quartzitic in part---------------.--------- 3 

Sandstone, purplish white, limy, very fine grained, and purple very fine sandy shale--------- 1 6 

Sandstone, greenish white, very fine grained--------------------------------------------- 1 7 

Sandstone, platy, white, fossiliferous, very fine grained, with purple, sandy shale partings. 

Fishplates------------------------------------------------------------------------- 2 4 

Sandstone, pink-mottled white, fine-grained. Forms ledge with unit below-------------.----- 10 6 

Sandstone, purple to white, limy, very fine grained, with abundant small red concretions 

and numerous shale partings----------------------------------------------------.------ 5 

Sandstone, pink-tinged white, very fine grained------------------------------------------- 2 

Sandstone, purple and white, shaly, very fine grained------------------------------------- 1 6 

Sandstone, purple- and white-banded, limy, very fine grained, with iron concretions up to 

1 inch in diameter. Forms ledge------------------------------------------------------ 3 2 

Sandstone, purple-mottled white, shaly, very fine grained------------------..:-------------- 8 

Sandstone, pinkish white, limy, very fine grained, containing scattered coarse sand grains 

and thin partings of red shale--------------------------------------------------------- • 3 3 

Sandstone, purple-mottled white, shaly, very fine grained--------------------------------- 8 

Sandstone, yellow-stained pink to white, fine grained. Top of lower ledge------------------- 1 9 

- 8 -
Ft. in. 

Sandstone, pinkish white, subangular to subround, coarse-grained-------------------------.,;~ 2 Sandsto~e, white, poorly sorted, limy, subangular to subround, fine- to coarse-grain~------, 1 4 

Sandstone, white, subround, coarse-grained, containing at base, white quartz pebbles, 1 

inch in diameter---------------------------------------------------------------------· 1 

Total thickness of Harding sandstone--------------------------------------------------1~ 1T 

(Underlain py pre-Cambrian gneiss and granite in Harding quarry) 

Manitou limestone 

(Measured with tape in Gnat Canyon in Shaws Park, 

NEt sec. 36, T. 17 S, R. 71 W.) 

Dolomite, dark-red, fossiliferous, medium crystalline, containing quartz geodes and 

Orthoceras-type cephalopods-----------~---------------------------------------------­

Dolomite, dark-red, fossiliferous, finely crystalline, containing nodules of white granular 

to dense chert. Gastropods and Orthoceras-type cephalopods abundant in top 6 inches-------

Dolomite, dark-red, finely granular to finely crystalline-----------------------------------

Dolomite, thin- and wavy-bedded, dark-red, finely granular to finely crystalline, with 

seams and nodules of white to tan granular to dense chert ito 1 inch thick------------------

Dolomite, red, finely granular, ·with two seams, t inch thick, of white granular chert--------

Dolomite, dark-red, finely granular----------------------------------------:..------------

Dolomite, red, granular, with one seam and two nodule horizons of slightly orange-mottled 

white spicular (?) devitrified to dense chert---------------------------------------------

Dolomite, dark-r:_d, medium. crystalline, with numerous layers, 2 to 4 inches thick, of 

white spicular devitrified to dense chert----------------------~------------------------­

Dolomite, dark-red, finely granular to finely crystalline-----------------------------------

Dolomite, dark-red, granular to medium-crystalline, with white dense chert showing 

dolomite crystal casts. Wavy basal surface---~---------------------------------------­

Total thickness of Manitou limestone---------------------------------------------------

Pre-Cambrian granite 

SECTION F. South Tunnel, Phantom Canyon, Fremont County, Colorado, 

NEt sec. 32, T. 17 S., R. 69 W. 

(.Measured by hand level and tape above and west of south tunnel on Phantom 

Canyon road.) 

Carboniferous 

Pennsylvanian rocks 

Fountain formation 

Sandstone, red, arkosic, coarse-grained 

Ordovician rocks 

Fremont limestone 

1 2 

3 10 

4 

5 7 

1 4 

1 8 

5 10 

5 

4 4 

3 6 

mr 3 

Dolomite, pinkish-red to yellow, granular, weathers like sandstone------------------------- 3 10 

Dolomite, yellow to pink, very finely banded, granular, grading downward into brown to red 

dense dolomite containing nodules of red and tan dense chert----------------------------- 3 9 

DolomUe, yellow, finely pink-banded, granular. Weathers like sandstone------------------- 1 6 

Dolomite, yellow-mottled red, fo'ssiliferous, granular, containing a little yellow dense chert-- 4 

Dolomite, yellow, pink, and red, medium- to coarsely crystalline-------------------------- 5 

Dolomite, pink to red, fossiliferous, medium- to coarsely crystalline; weathers rough. 

Crinoids, colonial corals, and Orthoceras-type cephalopods. Wavy basal contact---------.. - 5 

Total thickness of Fremont limestone---------------------------------------------------W 1 

Harding sandstone 

Sandstone, yellow, red, and pink, finely banded and cross-bedded, limy, very fine grained---- 3 1 

Sandstone, yellow to pink, fossiliferous, fine-grained. Abundant fish plates----------------- 5 6 

Sandstone, purple-mottled yellow, very fine grained--------------------------------------- 1 6 

Sandstone, white, very fine grained------------------------------------------------~----- 4 

Sandstone, white, slightly limy, very fine grained----------------------·------------------ 1 

Sandstone, blocky, pink and white, slightly limy, very fine grained, with intercalated pink 

fine sandy shale---------------------------------------------------------------------- 3 4 

Covered interval-----------------------------------------------------------------------· 16 

Sandstone, white, very fine grained------------------------------------------------------· 1 6 

Sandstone, massive, pinkish-white, very limy, fine-grained. Forms ledge------------------ 9 

Covered interval-------------------.------------;..----------·----------------------------- 15 6 

Shale, dull-red to brown, wa:x.y, in part green-spotted------------------------------------- 16 6 

Sandstone, medium-bedded, pink and white, slightly limy, fine-grained. Forms ledge-------- 4 3 

E'andstone, platy, purple, pink, and white, slightly limy, fine-grained, with intercalated 

purple fine sandy shale----------.:.---------------------------------------------------- 10 6 

- g -
Ft. 

sandstone,, platy, pink, purple, and white, fine-grained------------------------------------ 9 

Shale, thin-bedded, pink to red, sandy, and shaly sandstone containing irregular masses 

~ucoids?)--------------------------------------------------------------------------- 5 

Sandstone, hard, white to red, limy, fine- to coarse-grained-------------------------------

Total thickness of ~arding sandstone---------------------------------------------------1mf"" 

Manitou limestone 

Dolomite, medium-bedded, compact, dark-red, finely granular, with 3-inch layer of bonewhite finely mottled dense chert at to:tr------------------------------------------------- 1 

Dolomite, dark-red, finely granular, containing white to pink dense chert nodules, 3 to 6 

inches in diameter-------------------------------------------------------------:.. .. ----· 2 

Dolomite, dark-red, fossiliferous, finely granular. Orthoceras-type cephalopods-----------..1 2 

Dolomite, dark-red, finely granular, containing 1- to 2- inch layers of white to pink, finely 

granular chert----------------------------------------------------------------------- 2 

Dolomite, ·yellow-mottled purplish-red, slightly limy, finely granular----------------------- 4 

Dolomite, purple and brown, finely banded, fine sandy-------------------------------------

Dolomite, red, very cherty, finely granular; 75 percent of bed appears to be white to 

cream-colored dense chert-- ----------------------------------~-------------------~- 2 

Dolomite, red, limy, finely granular, with little white dense che~t-------------------------- 1 

Dolomite, thick-bedded, dark-red, granular to medium-crystalline------------------------- 3 

Dolomite, dark-red, very cherty, medium-crystalline. White to pink granular chert, and 

white microfossiliferous (?)or finely figured dense chert in layers and nodules, 1 to 2 

inches thick--------------·----------------------------------------------------------- 5 

Dolomite, hard, red, medium-crystalline, with white slightly mottled dense chert layers, 

1 to 3 inches thick, in lower part------------------------------------------------------ 5 

Dolomite, hard, red to yellow, finely granular to medium 'crystalline, with white dense to 

granular chert, and white mammillary chert in·layers 1 to 3 inches thick and about 6 

inches apart. Wavy basal contact------------------------------------------------------ 6 

Total thickness of Manitou limestone--------------------------------------------------- 'Jr'"' 

Pre-Cambrian granite and schist 

Carboniferous 

Pennsylvanian rocks 

Fountain formation 

SECTION F-1. Quarry, Phanto_m Canyon, fremont County, Colorado, 

NWt sec. 33, !r. 17 S., R. 69 W. 

(Measured by h8.l'l;d level and tape pn east side of Eight Mile Creek, 

3. 4 miles north of State Highway 120 on Phantom Canyon Road. ) 

Sandstone, red, arkosic, containing quartz pebbles 1 to 2 inches in diameter. 

Ordovician rocks 

Harding sandstone 

in. 

2 

4 

2 

8 

6 

4 

6 

4 

8 

3 

9 

2 

8 

1 

11 

Sandstone, yellow-, red-, and purple-stained, very fine grained---------------------------- 5 6 

Sandstone, pink- and yellow-mottled white, slightly limy., very fine grained------------------ 8 

Sandsto'ne, pink to white, very fine grained, containing abundant fish scales. Forms base 

of upper ledge----------------------------------------------------------------------- 5 6 

Sandstone, white, limy, very fine grained------------------------------------------------ 1 6 

Sandstone, pink, very fine grained------------------------------------------------------- 4 

Sandstone, white, platy, very fine grained, with thin red layers------------------------.----- 2 10 

Sandstone, white, very fine grained. Forms top of massive sandstone bed------------------- 4 

Sandstone, pink and white, very fine grained, grading into purple very fine grained sandstone 

containing abundant fish scales. F.orms base of massive sandstone bed-------------------- 5 

Sandstone, pink to purple, shaly, very fine grained, with fish scales------------------------ 2 

Covered interval. Maroon and brown shale partly exposed in places------------------------ 27 

Sandstone, white, platy, limy, very fine grained------------------------------------------ 6 8 

Sandstone, massive, white to pink, .slightly limy, very fine grained, with scattered 

"ironstone" concretions--------- ----------------------------------------------------- 10 4 

Sandstone, thin-bedded, white, very fine grained, interbedded with thin layers of purple· 

shale-----------------------------------------------------------------------~------- 3 3 

Shale, purple, with a few thin layers of white very fine grained sandstone-------------------- 1 2 

Sandstone, white, ·slightly limy, very fine grained----------------------------------------- 5 

Sandstone, pink, shaly, very fine grained, and sandy shale grading into maroon shale--------- 2 

Sandstone, hard, pink- and white-banded, very fine grained-------------------------------- 6 

Shale, purple------------------------------------------------------------------------- 1 1 

Sandstone, white, subangular to subround, coarse-grained------- -------·----------------- 3 

Total thickness of Harding sandstone--------------------------------------------------- gr 0 

- 10 -
Ft. in. 

Manitou limestone 

Covered interval. Contact not exposed--------------------------------------------------· 2 

Dqlomite, thick-bedded, red, slightly cherty, finely granular. White milky dense to finely 

granular. chert----------------------------------------------------------------------- 5 4 

Dolomite, thin-bedded to platy, red, slightly cherty, finely granular------------------------ 4 

Dolo mite, thick-bedded, red, finely granular--------------------------------------------- 3 11 

Dolomite, red, finely granular to medium crystalline, with 1- to 2-inch layers of tanmottled gray dense chert, red- and white-mottled dense chert, and white subtranslucent 

f~gured, dense chert--------~--------------------------------------------------------- 4 10 

Dolomite, red, compact, finely granular to medium crystalline, with scattered small nodules 

of bone-white faintly spicular (?) subtranslucent dense chert------------------------------ 4 10 

Dolomite, red, granular to medium crystalline, with 1- to 2-inch layers of white devitrified 

chert, red- and gray-mottled dense chert, and white subtranslucent chert with faintly 

visible spicules (?)------------------------------------------------------------------- 8 2 

Dolomite, red, compact, medium- to coarsely crystalline, with a small amount of white 

granular to dense chert and white mammillary chert------------------------------------- 4 6 

Total thickness of Manitou limestone---------;..----------------------------------------- W --rPre-Cambr~an schist 

SECTION F.-2. Cemetery Park, Fremont County, Colorado, 

s! sec. H~, T. 17 s., R. 68 W. 

Carboniferous 

Pennsylvanian rocks 

Fountain formation 

Sandstone, red, arkosic. 

Ordovician rocks · 

Fremont limestone 

(Measured by tape up northeast cliff of canyon, 

about 1 mile northwest of Beaver Creek road.) 

Dolomite, tan medium -crystalline------------------------------------------------------- 3 

Dolomite, pin.k-mottled tan, slightly porous, medium crystalline---------------------------- 10 

Dolomite, yellowish tan, finely granular, silty to very fine sandy--------------------------- 5 

Dolomite, pink-mottled yellowish tan, finely granular, very fine sandy; resembles finegrained sandstone on the outcrop------------------------------------------------------- 10 

Dolomite, pink, finely crystalline, alfd tan finely granular fine sandy dolomite---------------- 2 9 

Dolomite, red and yellow, granular, and pink medium -crystalline dolomite. Abundant small 

crinoids-------------------------------·--------------------------------------------- 4 

Dolomite, pinkish-red, granular to medium crystalline------------------------------------- 9 

Dolomite, pinkish-red, gr2nular to coarsely crystalline------------------------------------ 5 

Total thickness of Fremonf limestone----------------------------:.-------------·--------;m- 9 

Underlain by Harding sandstone and Manitou limestone which could not be accurately measured 

and sampled. 

,SECTION E. Oil Creek, Fremont County, Colorado, Tps. 16, 17 S., R. 70 W. 

Carboniferous 

Pennsylvanian rocks 

Fountain formations 

Sandstone, red brown, platy, shaly, medium-grained, resting on very irregular surface of Williams Canyon 

limestone. 

Mississippian rocks 

Williams Canyon limestone 

(Measured by hand level in dry tributary on east side of Oil Creek opposite Kansas 

University field camp, SEt sec. 4. T. 17 S., R. 70 W.) 

Dolomite, yellow-stained red and white, finely crystalline, slightly sandy in part------------- 6 

Dolomite, orange-mottled white, very finely granular to finely crystalUne-------------------- 4 

Limestone, red, yellow, and white, finely crystalline, dolomitic, and white slightly sandy 

medium crystalline dolomite----------------------------------------------------------- 5 6 

Dolomite, white to purple-banded white, finely crystalline to fine sandy---------------------- 5 6 

Dolomite, slightly yellow- and purple-tinged white,· very finely granular, in thin wavy beds---- 10 8 

Shale, soft, yellow and red, very fine sandy, with irregular basal surface----,-------------- 4· 

Total thickness of Williams Canyon limestone------------------------------------------- ~ 6 
Ordovician rocks 

Fremont limestone 

(Measured by hand level and tape on Trail Gulch road in Ni sec. 28, T. 16 ·s, 

R. 70W. 

Dolomite, red-mottled cream-colored, medium-crystalline, with numerous cavities filled with 

red silt. Forms top of cliff--·------------------------------------.;.------------------

Dolomite, red-mottled cream-colored, finely granular to finely crystalline-----------------· 

Dolomite, slightly pink-mottled yellowish buff, granular-----------------------------------

Dolomite, yellowish buff, granular, with some pink very fine grained dolomite in lower part:---

Dolomite, hard, yellow, finely granular to finely crystalline-------------------------------

Dolomite, hard, yellow, finely·granular, and limy dolomite--------------------------------

Dolomite, bright-yellow, finely granular---------------------------------------.:.--------.. 

Dolomite, gray buff finely granular, and red medium-crystalline dolomite-------... -----------

Dolomite, pinkish buff to red, fossiliferous, coarsely crystalline. Small crinoids near top. 

Pronounced irregularity at base-------------------------------------------------------

Total thickness of Fremont limestone-----------------------------------------------~--

Harding sandstone 

(Measured along Shelf road in swt sec. 27, T. 16 S., R. 70 W.) 

Ft. in. 

5 

5 

5 

11 6 

5 

4 

6 

4 6 

5 6 

or tr 

Sandstone, yellow-stained white, slightly limy, very fine grained--------------------------- 10 

Sandstone, purple-mottled white, fossiliferous, shaly, very fine grained. Abundant fish 

plates--------------------------------------------·--------------------------------- 8 

Sandstone, yellow-stained white, slightly limy, very fine grained--------------------------- 4 

Sandstone, purple, shaly, very fine grained---------------------------------------------· 6 

Sandstone, greenish white, very fine grained--------------------------------------------- 1 2 

Shale, blocky to platy, purple, sandy, with .intercalated lavender very fine grained 

sandstone-------------------------------~- ... ---------------------------------------- 5 6 

Sandstone, massive, white, fine-grained------------------------------------------------- 7 1 

Sandstone, purple, very fine grained---------------------------------------------------- 3 

Sandstone, white, very fine grained--------------------------------------..:-------------- g 

Sandstone, purple, fossiliferous, very fine grained. Abundant fish plates------------------- 3 

Sandstone, white, very fine grained, grading downward into purplish pink very fine grained 

sandstone containing scattered fish plates---------------------------------------------- 4 6 

Sandstone, pink and white, very fine grained--------------:------------------------------- 10 

Sandstone, massive, gray white, very fine grained---------------------------------------- 4 10 

Shale, white, fine, sandy----------------------------.:.---------------------------------- 2 

Sandstone, purple and lavender, very fossiliferous, shaly, very fine grained, grading 

downward into white fossiliferous very fine grained sandstone. Abundant fish plates-------- 2 

Shale, platy, bright purple, very fine sandy---------------------------------------------- 1 6 

Sandstone, white, limy, fossiliferous, very fine grained. Abundant fish plates-------------- 2 

Shale, platy, brown, fossiliferous. Small Orthoceras-type cephalopods--------------------- 2 

Shale, brownwaxy--------------------------------------------------------------------- 1 

Shale; purple to brown, waxy, containing a thin layer of very fossiliferous green waxy shale. 

Abundant gastropods and fish plates--------------------------------------------------- 3 

Shale, fissile, brown, waxy, green-spotted in part---------------------------------------- 12 6 

Shale, platy, brown, waxy, grading downward into platy purple sandy shale containing 

scattered white subround coarse sand grains. White very fine grained sandstone layer, 

3 inches thick, near middle of unit---------------------------------------------------- 5 6 

Sandstone, thin-bedded, pinkish-white, very fine grained, with irregular masses (fucoids?) 

and very thin layers of purple-maroon fine sandy shale. Forms top of ledge--------------- 5 

Sandstone, gray white to pinkish white, very fine grained---------------------------------- 21 

Sandstone, pinkish white, fine-grained, containing scattered white subround coarse quartz 

grains------------------------------------------------------------------------------ 2 

Sandstone, white, fine-grained, with scattered white coarse quartz grains-------------------- 6 

Sandstone, purple, maroon, and yellow, shaly, very fine grained--------------------------- 3 2 

Shale, purple maroon, sandy---------------------------------------------------~-------- 1 

Sandstone, yellow, subround, fine- to medium-grained------------------------------------ 1 2 

Shale, platy, maroon to purple, sandy, with bone-white chert fragments------------.. -------- 3 2 

Total thickness of Harding sandstone------------------------------------•-------------- ~ -r 

- 12 -
Ft. in. 

Manitou limestone 

(Measured below Shelf road in NWi sec. 34, T. 16 S., R. 70 W.) 

Top not exposed. Estimated covered interval--------------------------------------------- 3 

Dolomite, red, finely granular, .grading downward into pink medium-crystalline dolomite 

containing vugs of calcite-------------------------------------------------------------- 7 

Dolomite, pink sandy, granular. with included large subround quartz grains------------------ 5 

Dolomite, red, finely granular----------------------------------------------------------- 5 

Dolomite, pink, very sandy, with included large round quartz grains------------------------- 5 

Dolomite, pinkish buff, fine sandy, finely granular; weathers like sandstone------------------ 4 

Dolomite, pink to cream-colored, finely granular------------------------------------------ 5 

Dolomite, massive, pitted, pink and red, fossiliferous, granular to medium crystalline. 

Small horn corals. Forms ledge------------_:------------------------------------------ 7 

Dolomite, pink, yellow:, and white, finely granular to finely crystalline, containing 

scattered nodules of tan sub-translucent chert. Forms top of first ledge above creek-------- 6 10 

Dolomite, pinkish white, finely granular, and red medium-crystalline dolomite with trace of 

white devitrified chert-----------------------:------------------------------------------ 5 

Dolomite, yellow-tinged buff, medium-crystalline, containing several thin layers of whiteand tan-speckled chert, white devitrified mammillary chert, and white finely figured or 

spicular (?)chert--------------------------------------------------------------------- 3 

Dolomite, red, medium to co~sely crystalline, with many layers, -!to 1 inch thick, of 

gray-white to pink dense and spicular (?)chert------------------------------------------- 7 

Dolomite, pink to red, finely granular, medium crystalline; and coarsely crystalline dolomite 

with layers, -!to 1 inch thick, of white to tan spicular (?)dense chert---------------------- 3 

Dolomite, red, finely granular to medium crystalline--------------------------------------- 2 

Total thickness of Manitou limestone---------------------------------------------------- -grr- TO" 

Pre-Cambrian gneiss or gneissic granite 

SECTION G. Deadmans Canyon, .El Paso County, Colorado, SEi sec. 3, T. 16 S., 

R. 67 W. 

(Measured by hand level and tape at spring about one mile northwest of 

State Hmhway 115. Dip 34 o SE. ) 

Carboniferous 

Pennsylvanian rocks 

Fountain formation 

Sandstone, red, arkosic, COSJ'Se-grained. 

Ordovician r-ocks 

Harding sandstone 

(Measured by tape and corrected for 34 o SE dip. ) 

Sandstone, greenish white, subr.ound, fine-grained------------------------------------------ 8 5 

Shale, fissile, yellow, fine sandy---------------------------------------------------------- 2 

Shale, fissile, green-spotted maroon to purple----------------------------------------------- 3 9 

Shale, green-spotted maroon, grading downward into red very fine sandy-shale with very thin 

layers of white very fine grained sandstone----------------.:.------------------------------ 11 2 

Covered interval. Judging by float, this is red-brown shale-------------:--------------------- 5 7 

Shale, red brown, with thin intercalations of pale-green shale---------e":.---------------------- 6 2 

Covered interval, principally red-brown shale--------------------... .:..----- 7 ------------------ 2 10 

Shale, red brown, with intercalated pale-green shale----------:.-------:------------------------ 12 3 

Sandstone, greenish white, slightly limy, _fine-grained-----i---------------------------------- 2 3 

Shale, maroon, very fine sandy, and lavender very fine grained sandstone--------------------- 11 

Sandstone, greenish white, fine-grained, containing a few scattered coarse quartz grains-and 

intercalated red shale----------J------------------------------------------------------- 3 4 

Shale, waxy brown to maroon, fine sandy-------------------------------------------'-------- 5 7 

Sandstone, white fine-grained, with very irregular basal surface. Fills small caves and 

sinkholes in underlying Manitou limestone----:::------------------------------------------- 5 6 

Total thickness of Harding sandstone----------------------------------------------------~ -rr 

- 13-
Ft. in. 

Manitou limestone 

Measured by both hand level and tape up face of cliff. Dolomite, yellow-mottled red, finely 

to medium -crystalline----------------------------------------------------------------- 6 

Dolomite, yellow-mottled, finely granular------------------------------------------------- 4 

Dolomite red finely crystalline--------------------------------------------------------- 5 3 

Dolomite: red' and yellow, finely crystalline, with one 10-inch bed of red fine sandy dolomite. 

near base---------------------------------------------------------------------------- 10 

Dolomite, yellow to tan, finely granular to finely crystalline, grading downward into purple 

finely granular dolomite--------------------------------------------------------------- 6 

Dolomite, platy, lavender to purple, finely granular to medium-crystalline------------------- 4 

Dolomite, lavender, slightly sandy, finely granular---------------------------------------- 1 11 

Dolomite, pinkish red, finely granular, with thin .layers of white to yellow dense chert--------- 1 8 

Dolomite, pinkish red, finely granular---------------------------------------------------- 3 10 

Dolomite, lavender, finely granular, grading downward into thin-bedded red finely granular 

dolomite----------------------------------------------------~------------------------ 4 

Dolomite, purplish red to lavender, finely·granular, with some calcite---------------------:--- 4 2 

Dolomite, yellowish red, finely granular to mediur.n-crystalline, with trace of white milky 

chert at top-------------------------------------------------------------------------- 5 3 

Shale, red-mottled buff----------------------------------------------------------------- 2 

Dolomite, yellow-mottled red, medium-crystalline, containtng two very thin layers of 

pinkish-white subtranslucent chert in lower part----------------------------------------- 6 3 

Dolomite, yellowish brown, medium-crystalline, and red finely granular dolomite------------ 5 

Dolomite, red, finely granular to medium-crystalline-------------------------------------- 4 5 

Dolomite, red, finely granular, containing small quartz geodes and thin layers, ! to 1 inch 

thick, of buff dense chert and white faintly figured subtranslucent chert-------------------- 3 6 

Dolomite,· purplish red, medium-crystalline, with five layers, 1 to 5 inches thick, of 

white dense chert, pink chert, showing a few spicules, and white subtranslucent chert 

with yellow spots-------------------------~------------------------------------------- 4 8 

Dolomite, purplish red to pinkish red, finely granular-------------------------------------- 2 8 

Dolomite, red, medium-crystalline, with.thin layers, t inch thick, of bone-white to creamcolored dense chert--~---------------------------------------------------------------- 2 6 

Total thickness of Manitou limestone--------"'------------------------------------------- 80 --gPre-Cambrian gneiss 

SECTION H. Williams Canyon, El Paso County, Colorado, NWt sec. 32, 

T. 13 S. , R. 67 W. 

(Measured by hand level and tape beginning along east side of road 100 yards north of 

"The Narrows" and continuing on "Temple Drive" up the cliff to and above the "Cave 

of the Winds". ) 

Carboniferous 

Mississippian rocks 

Hardscrabble limestone 

Contact with Pennsylvanian rocks not exposed. Estimated interval that could not be measured 

andsampled------------------------------------------------------------------------- 15 

Dolomite, pinkish buff, finely to medium-granular----------------------------------------- 2 6 

Limestone, brown, finely crystalline to dense, grading downward into buff finely granular 

dolomitic limestone------------------------------------------------------------------- 5 6 

Limestone, white, fine, sandy, grading downward into buff, finely crystalline to dense 

lUnestone---------------------------------------------------------------------------- 5 6 

Limestone, buff to tan, finely <Jranular, dolomitic----------------------------------------- 3 

Limestone, cream-colored to pink, finely, to medium-crystalline, with abundant calcite-------- 8 

Dolomite, buff, granular, grading downward into brown finely crystalline limestone----------- 5 ·a 

Limestone, buff, medium-crystalline----------------------------------------------..,------ 6 

Limestone, cream-colored, finely crystalline, containing tan faintly figured dense chert and 

thin layers of tan granular dolomite---------------------------------------------------- 6 

~imestone, faintly red- and yellow-mottled, finely crystalline, and gray-white finely granular 

dolomitic limestone------------------------------------------------------------------- 5 6 

Limestone, yellow-stained cream-colored, fin~ly granular, dolomitic, and pink finely 

granular dolomite. Reddish-brown to yellowish-red subtranslucent dense chert------------- 6 6 

Sandstone, gray, poorly sorted, limy, subround, f1ne- to medium-grained; pink limy fine- to 

medium-grained sandstone, pink finely granular dolomite, and pinkish-buff limestone 

conglomerate with included clay pellets. The base of this unit appears to mark an 

unconformity------------------------------------------------------------------------- 5 6 

- 14 -
Limestone, brown, dense; missing 5 feet east along outcrop-------------------------------

Limestone, yellow-stained cream-colored, finely crystalline, and dolomitic limestone-------

Dolomite, buff to tan, finely granular, containing one lens of gray- and buff-mottled dense 

chert----------------------------------------------------------------------~-------

Dolomite, light-buff, very finely granular-----------------------------------------------

Dolomite, pink to cream-colored, finely granular...;.----------------------------------------

Dolomite, buff, slightly micaceous, finely granular, with yellow and white dense to granular 

chert-------------------------------------------------------------------------------

Limestone, pink-tinged buff, fine sandy--------------------------------------------------

Limestone, pink-banded buff, micaceous, sandy and dolomitic, with irregular basal 

surface----------------------------------------------------~------------------------

Total thickness of Hardscrabble limestone----------------------------------------------

Williams Canyon limestone 

Dolomite, pink- to maroon-mottled yellowish-bUff, sandy; missing 10 feet east along 

outcrop----------~------------------------------------------------------------------

Sandstone, pink to white, dolomitic, fine-grained, and yellow-stained buff finely granular 

dolomite--------------------------~-------------------------------------------------

Dolomite, hard, purple, maroon, and yellow, slightly sandy, very finely granular------------

Shale, purple, maroon, and yellow, fine, sandy-------------------------------------------

Sandstone, gray, very limy, fine-grained------------------------------------------------

Limestone, maroon- and yellow-mottled buff, slightly dolomitic, finely crystalline-----------

Shale, yellow tan, very limy; gray-green, fine sandy shale, and yellow-white fine- to 

medium-grained sandstone-----------------------------------------------------------

Limestone, thin-bedded, brown, finely crystalline; and red-brown, finely crystalline 

dolomitic limestone------------------------------------------------------------------

Limestone, soft, white to buff, sandy; red dense dolomite; and tan limy shale----------------

Sandstone, poorly exposed beds, gray buff, limy, fine-grained; and poorly exposed beds of 

brown finely crystalline limestone, and red-buff finely granular dolomite. Estimated-------

Siltstone, tan, limy and in part finely sandy----------------------------------------------

Dolomite, red to brown, finely crystalline, in -part fine sandy------------------------------

Dolomite, yellow-stained, fine sandy, and gray-white very limy fine-grained sandstone, 

containing limestone pebbles. Irregular basal surface----------------------------------

Total thickness of Williams Canyon limestone------------------------------------------

Ordovicic. n rocks 

Manitou limestone, restricted 

Dolomite, massive, yellow-stained, slightly pink-tinged buff, medium-crystalline------------

Dolomite, massive, pink to buff, medium to coarsely crystalline, containing light-buff 

chert with faintly visible figures. Very-thin layer of white round- medium-grained 

sandstone near base. First bed above Cave of Winds parkway-----:-----------:.:-:.::.--.=-.:.::-":', 

Dolomite, pitted, massive, yellow-stained pink to buff, medium- to coarsely crystalline, 

containing light-buff slightly figured or fossiliferous chert. First bed below Cave of 

Winds parkway----------------------------------------------------------------------

Limestone, gray, medium-crystalline, dolomitic, grading downward into pink-tinged 

gray finely crystalline limestone------------------------------------------------------

Dolomite, pink, fine sandy; and buff finely granular dolomite-------------------------------

Limestone, purple-mottled buff, finely crystalline to dense--------------------------------

Dolomite, buff to brown, finely granular, limy-------------------------------------------

Dolomite, hard, gray buff to buff, finely granular----·--------- ---------------------------

Dolomite, pinkish buff, finely granular--------------------------------------------------

Dolomite, platy, buff, finely granular---------------------------------------------------

Limestone, buff, finely crystalline-..-----------------------------------------------------

Limestone, slightly yellow-stained gray buff, finely crystalline, containing gray and buff 

dense chert nodules------------------------------------------------------------------

Limestone, massive, buff to tan, microfossiliferous, finely crystalline---------------------

Limestone, platy, gray, dense-------~-------------------------------------------------­

Limestone, dark-buff, finely crystalline to dense----------------------------------:-------

Limestone, brown, dense-------·-------------------------------------------------------

Limestone, purplish buff, fossiliferous, glauconitic, medium-crystalline-------------------

Limestone, slightly pink-tinged buff, glauconitic, finely crystalline to dense-----------------

Limestone, pink-tinged buff, medium-crystalline-----------------------------------------

Limestone, cream-colored, finely granular, dolomitic------------------------------------

Dolomite, slightly yellow-stained buff, granular-~---------------------------------------­

Limestone, thin-bedded, buff, faintly oolitic, finely crystalline---.:------------------------

Limestone, cream-colored, finely to medium-crystalline, with two layers of cream-colored 

spicular chert nodules. Upper part is faintly oolitic------------------------------------

Dolomite, pink-mottled buff, finely granular---------------------------------------------

- 15 -

Ft. in. 

o 

1 7 

5 6· 

5 6 

4 

3 6 

2 6 

2 6 

-roo -a 

2 

2 6 

1 8 

4 

1 6 

3 

1 8 

2 6 

1 3 

10 

10 

2 2 

10 

"30" --r 

7 

7 

4 

5 5 

2 

1 6 

2 

7 10 

1 11 

6 

2 9 

3 9 

6 9 

10 

2 4 

7 

6 

3 5 

4 8 

5 8 

3 

2 6 

6 9 

3 3 
Ft. in. 

Limestone, buff, finely crystalline-------------------------------------..... --------------- -6- 1 

Dolomite, reddish buff, finely crystalline to finely granular; and buff finruy crystalline 

lime.stone--------------------------------------------------------------------------- 6 

Limestone, cream-colored, finely crystalline, with included drusy quartz----------..:________ 9 2 

Limestone, buff, finely to medium-crystalline; and dolomitic limestone containing white 

devitrified spicular chert------------------------------------------------------------- 3 10 

Limestone, buff, finely crystalline, and· buff finely granular dolomitic limestone, with 

six 2-inch layers of gray spicular dense chert----------------------------------.: ........ :...... 5 

Limestone, buff, finely crystalline, grading downward into buff finely granular dolomite------ 11 5 

Limestone, buff, finely crystalline---------------------------------------------------·-- 4 1 

Limestone, pink-tinged gray to buff, finely crystalline, with a thin layer of buff very 

glauconitic oolitic to pisolitic microfossiliferous finely crystalline limestone about 

2 feet below top---.. -----------------------------------------------------------·----- 5 

Dolomite, yellow-stained buff, fin~ly granular, grading downward into buff slightly oolitic 

finely crystalline limestone---------------.. -----·-------------------.. --.. -------------- 4 3 

Limestone, cream-c0lored, slightly glauconitic, faintly oolitic, finely crystalline------------ 2 

Dolomite, yellow-stained cream-colored, finely granular---------------------------------- 9 

Dolomite, pink, finely granular--------:.................................................................................................. 2 

Limestone, buff, finely crystalline, containing pyrite and white- to tan-figured chert--------- 4 2 

Limestone, thin-bedded, buff, finely crystalline, and dolomitic limestone-----------·----·-- 6 6 

Limestone, buff, finely crystalline, with calcite and iron concretions------------·-------·-- 3 9 

Limestone, thin-bedded, buff, finely crystalline, with traces of galena, calcite, and 

glauconite. Lower 4-inch bed is very shaly------------..:.------------------------------- 2 5 

Limestone, thin-bedded, cream-colored, finely crystalline to dense, with traces of 

galena, hematite, and glauconite------------------------------------------------------ 5 5 

Limestone, thin-bedded, buff, fossiliferous, finely to medium .. crystalline, and dolomitic 

limestone with trilobites and trace of cream-colored finely figured dense chert. 

Kainellasp.--------------------------------------------------------·--------------- 5 6 

Limestone, platy, dark-buff, finely crystalline to finely granular, dolomitic--·------.-------- 3 6 

Limestone, thin-bedded, brown, finely crystalline, and dolomitic limestone----------------- 3 

Limestone, brown, medium-crystalline, with paper-thin black shale partings, organic 

material, and limestone pebbles. Slightly wavy basal surface, possible unconformity-----·- 5 

Dolomite, slightly yellow-stained pinkish red, glauconitic, granular; and buff finely 

crystalline dolomitic limestone-----------.:.-----------------------------------... -------- 3 4 

Dolomite, ptirplish-red, fossiliferous, coarsely crystalline, with calcite and Orthocerastype cephalopods--------------------------------------------------------------------- 1 11 

Limestone, thin-bedded, finely crystalline, dolomitic------:............................................................. 1 3 

Total thickness of Manitou limestone, restricted-------------... -------------------------- T8'6 8 

Cambrian rocks 

Ute Pass dolomite 

Dolomite, purplish red to buff, coartiely crystalline----------------------.. ----... -~--------- 1 2 

Dolomite, thin-bedded, purplish red to buff, granular to coarsely crystalline, with 

dendrites on bedding surfaces and paper-thin green shale partings------------------------ 4 4 

Dolomite, dark-red, finely crystalline and granular--------------------------------------- 3 8 

Dolomite, dark-red, very glauconitic, coarsely crystalline, with wavy basal surface--·-------- 5 

Total thickness of Ute Pass dolomite--------------------------------------------------- """""f.4 2 

Cambrian rocks 

Sawatch quartzite 

Sandstone, platy, green gray, very glauconitic, fine-grained------------------------------- 2 

Sandstone white to red glauconitic subround- medium-grained-------------------------- 1 2 

Dolomite,' red, very gl~uconitic, ve~y sandy, c~arsely crystalline, grading downward into 

red very glauconitic fine- to medium-grained dolomitic sandstone-------------.------------ 6 6 

Sandstone, red, glauconitic, fine- to medium-grained, dolomitic and red glauconitic coarse 

sandydolomite---------~-------------------------~---------------------------------- 4 1 

Sandstone, red, glauconitic, fine- to coarse-qrained, dolomitic---------------------------- 5 6 

Dolomite, red, glauconitic, coarsely crystalline, with included large round sand grains------- 5 4 

Dolomite, dark-red, very glaucohitic, coarsely crystalline, sandy-------------------------- 1 6 Dolomite, red, fine sandy----------------------------.:. _________________________________ :. 4 

Dolomite, dark-red, very glauconitic, coarsely crystalline-------------------------------- 1 2 

Dolomite, red, finely crystalline, sandy, grading downward into red glauconitic slightly 

feldspathic subangular coarse-grained dolomitic sandstone------------------------------- 4 2 

Sandstone, red to pink, glauconitic, feldspathic, subround- to subangular, medium ... to 

coarse-grained, dolomitic------------------:__________________________________________ 6 8 

Sandstone, white, feldspathic, subround, coarse-grained, slightly dolomitic----------.... ------ 3 7 

Sandstone, pink to buff, fine- to medium-grained, with thin maroon shale partings------------ 9 

Sandstone, pink to wl1ite, slightly feldspathic, fine• to medium-grained, dolomitic------------ 7 9 

- 16 -
Ft. in. 

Sandstone, green-spotted purple, subround-, medium-grained----------------------------- 8 

Sandstone, white, slightly feldspathic, subround-, medium- to coarse-grained--------------- 1 1 

Sandstone, white, subround, coarse-grained, with white quartz pebbles up to 3 inches in 

diameter. Wavy basal surface-----------------------------------------------·-------- 3 

Total thickness of Sawatch quartzite--------------------------------------------------- -mJ 8 

Pre-Camprian ~anite 

SECTION I. Missouri Gulch, Douglas County, Colorado, Ei sec. 34, T. 10 S., 

R. 69W. 

Carboniferous 

Pennsylvanian rocks 

Fountain formation 

Mississippian rocks 

Hardscrabble limestone 

(Measured by hand level up north face of quarry.) 

Limestone, pink to gray, coarsely crystalline, capping hill. Approximate top of limestone 

formerly called Madison at this locality-----------------------------------------------

Dolomite, pink, medium- to coarsely crystalline-----------------------------------------

Dolomite, pink to gray-white, granular to coarsely crystalline-----------------------------

Dolomite, pink, finely granular; and buff finely crystalline limestone containing a small 

amount of brown dense chert---------------------------------------------------------

Limestone, cream-colored to buff, finely crystalline, grading downward into cream-colored, 

microfossiliferous, dense dolomitic limestone--------:----------------------------------

Limestone, tan, dense, gradin<J downward into pink-buff finely granular dolomite with thin 

layer· of pink-white fine-grained sandstone at base. Forms base of ledge-----------------

Covered interval. Contact of Hardscrabble and Williams Canyon limestones in this 

interval---------------------------------------------------------------------------· 

2 

2 6 

5 6 

5 6 

1 6 

5 6 

18 6 

Total thickness of Hardscrabble limestone--------------------------------------------- 4r -o 

Williams Canyon limestone 

Sandstone, hard, lavender, quartzitic, subround-, fine-grained---------------------------- 6 

Sandstone, lavender, limy, fine- to medium-grained-------------------------------------- 1 9 

Limestone, cream -colored, finely crystalline-------------------------------------------- 1 

Sandstone, 'pink, limy, medium-grained------------------------------------------------- 8 

Shale, platy, lavender, limy----------------------------------------------------------- 1 

Dolomite, thin-bedded, lavender and gray, very finely granular, fine sandy in part---------- 2 8 

Dolomite, thin-bedded, lavender to cream-colored, finely granular to fine sandy------------ 6 6 

Dolomite, lavender, fine sandy, grading downward into thin-bedded, purple-mottled buff 

finely granular dolomitic limestone and finely crystalline limestone---------------------- 5 6 

Dolomite, thin-bedded, purple-mottled lavender, very finely granular, and dolomitic 

limestone-------------------------------------------------------------------------- 5 6 

Dolomite, thin-bedded, purple-banded gray buff, finely granular, grading downward into 

purple-banded gray-buff finely crystalline dolomitic limestone--------------------------- 5 6 

Lime,stone, purplish gray, finely crystalline, dolomitic----------------------------------- 10 

Shale, platy, gray, limy--------------------------------------------------------------- 1 

Limestone, thin-bedded, lavender, finely granular, dolomitic----------------------------- 3 

Limestone, platy, gray, finely crystalline----------------------------------------------· 2 

Sandstone, purple-mottled green, limy, conglomeratic------------------------------------ 2 

Shale, green, slightly limy, fine sandy-------------------------------------------------- 4 

Total thickness of Williams Canyon limestone------------------------------------------ ~ --r 

Ordovician rocks 

Manitou limestone 

Limestone, red-mottled tan, finely crystalline------------------------------------------- 6 

Limestone, purple-mottled gray buff, finely crystalline----------------------------------- 1 6 

Dolomite, red to lavender, medium-crystalline-----------------------------------.:,______ 3 11 

Dolomite, massive, red, medium-crystalline, containing· ferruginous material grading 

downward into red-mottled buff finely crystalline limestone------------------------------ 5 6 

Dolomite, massive, pink to purplish red, very finely granular----------------------------- 5 8 

Dolomite, massive, slightly yellow-mottled purplish red, medium-crystalline--------------- 5 6 

Dolomite, massive, purplish red, very finely granular, limy, containing calcite. Yellowstained in part----------------------------"'.----------------------------------------- 4 2 

Dolomite, massive, purple-mottled red, very. finely granular, containing some calcite------- 4 8 

Dolomite, massive, purplish red, finely granular---------------------------------------- 4 2 

- 17 -
Limestone, purple-mottled gray, very fossiliferous, coarsely crystalline. Abundant 

trilobites and brachiopods------------------------------------------------------------

Limestone, rubbly, purple-mottled gray, finely crystalline------------------------.:. ______ _ 

Limestone, red, fossiliferous, finely crystalline, with abU.ndant brachiopods on upper surface. 

Apheoorthis sp.-------------~--------------------------------------------------------

Li~estone, ~ubbly, purplish re4 and buff, finely crystalline to dense, with gray-green limy. 

shale partings-----------------------------------------------------------------------

Limestone, red,~ fossiliferous, finely to medium-crystalline, dolomitic, with abundant 

brachiopods and trilobites on upper surface. Nanorthis sp., Apheoorthis sp. -------------

Dolomite, rubbly, red-mottled gray, fossiliferous, finely to medium-crystalline, with graygreen fissile limy shale partings. Brachiopods abundant near middle; trilobites and 

brachiopods abundant at top. Apheoorthis sp. ------------------------------------------

Dolomite, red, fossiliferous, medium-crystalline, grading downward into buff coarsely 

~ cr~alli_!le limestone. Small pelecypods and gastropods abundant near top. Nanorthis sp. , 

Apheoorthis sp::-i..e!OSteglilm sp.-, HY5Er!cUrUS-sp. ----------------------------------------= Lim~stone, rubbly, tan, finely crystalline, with greenand purple shale partings---------------

Limestone, gray.buff, very fossiliferous,. finely to coarse1fcrysta'l1ine. Abundant gastropods 

and trilobites. Nanorthis sp .. , Apheoorthis sp. , Finkelnburgia sp. , snail-like Sinuites-----

Dolomite, red, medium- to coarsely crystalline------------------------------------------

Limestone, rubbly, yellow-stained buff, finely to coarsely crystalline, with green sandy 

shale partings-----------------------------------------------------------------------

Dolomite, red, slightly glauconitic, medium-crystalline, with included biotite mica flakes-----

Limestone, gray-buff, fossiliferous, glauconitic, coarsely crystalline, with one 8-inch 

bed of red glauconitic coarsely crystalline dolomite near middle. Brachiopods abundant----

(Measured by hand level along south bank of creek) 

Dolomite, thin-bedded, red, glauconitic, coarsely crystalline, grading downward into grayFt. in. 

4 

1 

1 4 

2 1 

11 

4 6 

1 2 

2 2 

6 

2 2 

1 1 

2 2 

4 4 

buff glauconitic coarsely crystalline limestone------------------------------------------ 5 6 

Limestone, red to buff, glauconitic, coarsely crystalline, grading downward into red 

glauconitic conglomeratic limestone w~ich contains gastropods, green shale fragments, 

and fine sand grains------------------------------------------------------------------ 3 6 

Limestone, red, finely crystalline, dolomitic--.------------------------------------------- 2 

Dolomite, poorly exposed, thin-bedded, purplish red, slightly fossiliferous, finely granular, 

and pink to purplish-gray finely crystalline limestone-------:----------------------------- 4 6 

Shale, platy, brown, slightly glauconitic, micaceous--------------------------------------- 1 

Total thickness of Manitou limestone--------------------------------------------------- -.,n- --roCambrian rocks 

Ute Pass dolomite 

Dolomite, alternating thick- ·and thin-bedded, red, very glauconitic, coarsely crystalline, 

containing calcite-------------------------------------------------------------------- 4 10 

Shale, platy, brown-------------------------------------------------------------------- 6 

Dolomite, thin-bedded, red, glauconitic, micaceous, fine sandy, finely granular, grading 

downward into red glauconitic, coarsely crystalline dolomite----------------------------- 5 6 

Dolomi}e, thin-bedded, red, very glauconitic, medium- to coarsely crystalline, with 

included mica and sand grains. Contact of Ute Pass dolomite and Sawatch quartzite is not 

exposed but this bed which was excavated is probably within 5 feet of contact--------------- 5 6 

Total thickness of Ute Pass dolomite--------------------------------------------------- J:6 ----;r 

Cambrian rocks 

Sawatch quartzite 

(Measured by hand level up north side of gulch 250 yards east of quarry.) 

Covered interval, estimated------------------------------------------------------------ 5 

Sandstone, brown to purple, slightly limy, subround, fine- to coarse-grained----------":"----- 4 6 

Sandstone, purple, slightly limy, subround, medium-grained. Sand grains show secondary 

enlargement in part----------------------------------~------------------------------- 11 

Sandstone, bright yellow, poorly sorted, slightly limy, fine- to medium-grained, grading 

downward into purple-mottled yellow slightly limy fine-grained sandstone----------------- 5 6 

Sandstone, red to pinkish-white, well-sorted, slightly limy, fine- to medium-grained-------- 16 6 

Sandstone, alternating beds of pink and white, slightly limy, subround-, fine- to mediumgrained-------------------------------------~--------------------------------------- 5 6 

Sandstone, pink, poorly sorted, slightly limy, fine- to coarse-grained---------------------- 9 6 

Sandstone, yellow, subround-, fine- to medium-grained----------------------------------- 1 6 

Sandstone, very friable, tan, subround-, medium-grained, grading downward into reddishbrown subround medium-grained sandstone--------------------------------------------- 5 6 

- 18 -
Ft. in. 

Sandstone, ferruginous red to tan, poorly sorted, slightly feldspathic, slightly limy, 

fine- to coarse-grained, with some secondary quartz------------------------------------ 5 6 

Sandstone, ferruginous brown and red, slightly limy, subround fine- to coarse-grained------- 5 6 

Total thickness of Sawatch quartzite--------------------------------------------------- -rrJ '"6"" 

Pre-Cambrian granite 

SECTION J. Gove Canyon, Douglas County, Colorado, NEt sec. 2, T. 10 S., 

R. 68W. 

(Measured by hand level and tape on west side of Gove Creek. ) 

Carboniferous 

Pennsylvanian rocks 

Fountain formation 

Clay-, red, with limestone and chert boulders, some of which contain brachiopods of 

Mississippian age. 

Mississippian rocks 

Williams CanyQn limestone 

Dolomite, pink, finely granular to finely crystalline--------------------------------------- 2 

Dolomite, poorly exposed, hard, pink, finely to medium-crystalline, with conchoidal 

fracture---------------------------------------------------------------------------- 5 6 

Dolomite, poorly exposed, red, lavender, and gray buff, finely granular-------------------- 5 6 

Sandstone, red, lavender, and white, slightly limy, fine- to medium-grained---------------- 1 3 

Dolomite, blocky, lavender, finely crystalline-------------------------------------------- 1 8 

Dolomite, lavender to buff, finely granular, sandy in part---------------------------------- 4 2 

Sandstone, lavender, dolomitic, fine- to medium-grained---------------------------------- 4 

Dolomite, lavender, fine sandy---------------------------------------------------------- 4 

Dolomite, lavender, finely granular to finely crystalline----------------------------------- 6 

Dolomite, thin-bedded, lavender and buff, slightly sandy, finely granular, and compact 

lavender finely granular dolomite----------·-------------------------------------------- 4 

Dolomite, thin-bedded, lavender, finely granular to fine sandy, with 4-inch bed of lavender 

dolomitic fine-grained sandstone near middl_e------------------------------------------- 4 

Dolomite, thin-bedded to rubbly, hard, lavender, finely granular, with included 

subround sand grains----------------------------------------------------------------- 4 6 

Dolomite, platy, fine sandy---------------------------------.:.--------------------------- 3 

Dolomite, thin-bedded to rubbly, pink, finely granular, and yellow- and purple-mottled 

lavender finely granular dolomite----------------------------------------.. ------------- 4 9 

Siltstone, thin-bedded to rubbly, lavender dolomitic; lavender finely granular, dolomite with 

calcite; and red to purple finely granular dolomite-------------------------------------- 5 2 

Shale, platy, purple, slightly dolomitic, with irregular basal surface----------------------- 6 

Total thickness of Williams Canyon limestone------------------------------------------- """4r -:5'"" 

Cambrian rocks 

Ute Pass dolomite 

Dolor:pite, medium-bedded, red, very glauconitic, sandy, interbedded with red glauconitic 

dolomitic fine-grained sandstone------------------------------------------------------ 5 

Dolomite, medium-bedded, red, very glauconitic, sandy to coarsely crystalline, with green 

layers of glauconite between beds. Calcite vugs in upper 1 foot--------------------------- 3 6 

Total thickness of Ute Pass dolomite--------------------------------------------------- -s ~ 

Cambrian rocks 

Sawatch quartzite 

Sandstone, hard, brown to tan, well-sorted, glauconitic, calcareous, subround, medium- to 

coarse-grained-----------------------------------·---------------------------------- 5 6 

Sandstone, hard, brown to tan, subround, medium- to coarse-grained------------·---------- 4 2 

Sandstone, friable, finely brown-banded white and tan, poorly sorted, subround, fine- to 

coarse-grained-------------- -------------------------------~---------------~------- 4 10 

Sandstone, friable, white to brown, subround, fine- to medium-grained-~------------------- 8 2 

Sandstone, friable, brown, subround, fine- to medium-grained, grading downward into 

pinkish-white to tan finely brown-banded subround medium-grained sandstone-------------- 5 10 

Sandstone, friable, white to brown, subround, fine- to medium-grained, with considerable 

iron staining at top------------------------------------------------------------------- 4 9 

Sandstone, friable, white, subround, fine- to medium-grained, grading downward into white 

finely brown-banded subround fine- to medium-grained sandstone-----------------~------- 6 

Sandstone, friable, brown, subround, fine-grained---------------------------------------- 4 

Sandstone, friable, white, finely red-banded, subround, fine- to medium-grained------------- 4 9 

- 19 -
Ft. in. 

Sandstone~ friable, pinkish-white, subround, slightly feldspathic, fine- to medium-grained---- 7 4 

Sandstone, dark reddish brown, limy, fine- to medium-grained, with ferruginous hard 

layers----------------------------------------------------------------------.-------- 3 2 

Sandstone, iron-stained white, subround, fine- to coarse-grained, containing ferruginous 

hard nodules and layers, and scattered quartz pebbles. Cross-bedded in part-------------- 1 6 

Sandstone, friable, white, slightly feldspathic, subround fine- to medium-grained ... _______ .;. ____ · 3 

Sandstone, friable, pink-, purple-, and yellow-tinged white, subround, fine- to mediumgrained----------------------------------------------------------------------------- 11 6 

Sandstone, very friable, white, yellow, and pink, subround-, medium- to coarse-grained----- 6 11 

Sandstone, friable, white, fine- to medium-grained, grading downward into hard white 

feldspathic subround to subangular coarse-grained sandstone, with white quartz pebbles 

(t-inch in diameter) at base. Smooth basal contact-------------------------------------- 5 6 

Total thickness of Sawatch quartzite---------------------------------------------------- "'8tr 1r 

Pre-Cambrian granite 

LITERATURE CITED 

Collins, J. B., 1947, Subsurface geologic cross section-from Trego County, Kansas to. Cheyenne County, Colo.: 

Univ. Kansas Pubs., State Geol. Survey of Kansas, Oil and Gas Invest., Prelim. Cross Section 5. 

Edson, F. C., 1945, Subsurface geologic cross section from Ford County to Wallace Co;unty, Kansas: Univ. 

Kansas Pubs., State Geol. Survey of Kansas, Oil and Gas Invest., Prelim. Cross Section 1. 

1947, Subsurface geologic cross section from Ford County, Kansas to Dallam County, Texas: Univ. Kansas Pubs. , 

State Geol. Survey of Kansas, Oil and Gas Invest., Prelim. Cross Section 3. 

Maher, J. C. , 1946, Subsurface geologic cross section from Ness County, Kansas to Lincoln County, Colo. : Univ. 

Kansas Pubs., State Geol. Survey of Kansas, Oil and Gas Invest., Prelim. Cross Section 2. 

1947, Subsurface geologic cross section from Scott County, Kansas to Otero County, Colo. : Univ. Kansas Pubs. , 

State Geol. Survey of Kansas, Oil and Gas Invest. , Prelim. Cross section 4. 

1948, Subsurface geologic cross section from -:Baca County to Yuma County, Colo.: Univ. Kansas Pubs., State 

Geol. Survey of Kansas, Oil and Gas Invest., Pr~lim. Cross Section 6. 

1950, Pre-Pennsylvanian rocks along the Fr~nt Range of Colorado: U. S. Geol. Survey, Oil and Gas Invest., 

Prelim. Chart 39. 

Maher, J. S. and Collins, J. B., 1949, Pre-Pennsylvanian geology of southwestern Kansas, northeastern Colorado, 

and the Oklahoma Panhandle: U. S. Geol. Survey, Oil and Gas Invest., Prelim. Map 101. 

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