Sturgis Formation 

(Upper Pennsylvanian), 

a New Map Unit in the 

Western Kentucky Coal Field

GEOLOGICAL SURVEY BULLETIN 1394-B

Work done in cooperation with the 

Kentucky Geological Survey
'\
Sturgis Formation 

(Upper Pennsylvanian), 

a New Map Unit in the 

Western Kentucky Goal Field

By THOMAS M. KEHN

CONTRIBUTIONS TO STRATIGRAPHY

GEOLOGICAL SURVEY BULLETIN 1394-B

Work done in cooperation with the 

Kentucky Geological Survey

A clarification and revision 

of the stratigraphic terminology 

and a description of the rocks 

of Late Pennsylvanian age

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1973
UNITED STATES DEPARTMENT OF THE INTERIOR 

ROGERS C. B. MORTON, Secretary

GEOLOGICAL SURVEY 

V. E. McKelvey, Director

Library of Congress catalog-card No. 73-600237

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

Washington, D.C. 20402 Price 35 cents (paper cover)

Stock Number 2401-02408
CONTENTS

Page

Abstract ______ Bl

Introduction ____ _ 1

Previous nomenclature ______ - , - -- - 2

Lisman Formation ______ 2

Henshaw Formation ______________ _ _ _ 3

Sturgis Formation _________ 4

Providence Limestone Member ___________ __ _ 8

Anvil Rock Sandstone Member __ 9

Madisonville Limestone Member _ __ _ _ 9

Carthage Limestone Member ____ 10

Contacts ___________________________ ______ 10

Location of drill holes ______________ _ _ 11

Sections of the Sturgis Formation _____________ ____ _ 11

Upper section _______________________________ 11

Middle section _ ______________________________ 12

Lower section _______________________________ 22

References cited _________________________________ 23

ILLUSTRATIONS

Page

FIGURE 1. Correlation chart showing the nomenclature of this report

and of earlier reports ____________________ B2

2. Index map of part of the western Kentucky coal field 

showing localities and quadrangles referred to in this 

report _______________________________ 4

3. Index map showing the western Kentucky coal field and

the type area of the Sturgis Formation ________ 5

4. Diagram showing correlation of measured core sections 

and of the rocks penetrated by the Cities Service Oil 

Co. stratigraphic test hole Camp Breckinridge 1891 _ 7

in

CONTRIBUTIONS TO STRATIGRAPHY

STURGIS FORMATION (UPPER 

PENNSYLVANIAN), A NEW MAP UNIT IN 

THE WESTERN KENTUCKY COAL FIELD

By THOMAS M. KEHN

ABSTRACT

The Sturgis Formation is a new rock-stratigraphic unit which includes all 

Upper Pennsylvanian strata in the western Kentucky coal field. Geologic 

investigations reveal that the strata previously assigned to the Lisman and 

Henshaw Formations cannot be distinguished or mapped on the basis of 

lithologic differences; these names are abandoned. The Sturgis Formation 

consists of interbedded sandstone, siltstone, shale, limestone, and coal. It 

has a thickness of about 2,075 feet in a fault block in the Sturgis, Ky., area. 

The Providence Limestone, Anvil Rock Sandstone, Madisonville Limestone, 

and Carthage Limestone, all former members of the Lisman Formation, are 

retained as members of the Sturgis Formation. The Sturgis overlies the 

Carbondale Formation, and the contact between the formations is placed at 

the top of the No. 11 coal bed.

INTRODUCTION

Detailed geologic investigations in the Kentucky part of the 

Dekoven Ti/a-minute quadrangle and the Bordley and Sturgis T 1/^- 

minute quadrangles and reconnaissance studies in the Dixon TVaminute quadrangle of the western Kentucky coal field reveal that 

the Lisman and Henshaw Formations of Late Pennsylvanian age 

are composed of similar lithologies and cannot be distinguished 

or mapped on the basis of lithologic differences. Therefore the 

rocks formerly assigned to these two units are here assigned to 

the Sturgis Formation, a new stratigraphic unit, and the names 

Lisman and Henshaw are abandoned. The Providence Limestone, 

Anvil Rock Sandstone, Madisonville Limestone, and Carthage 

Limestone, all former members of the Lisman Formation, are 

retained as members of the Sturgis Formation. A summary of 

the nomenclature is given in figure 1.

Bl
B2 CONTRIBUTIONS TO STRATIGRAPHY

E

(0 °

c

LL.

Owen (1857)

Carthage Limestone

Anvil Rock Sandstone

Top of No 11 coal bee/

C £

u_

c 

E

^

c

i

Glenn (1912a,b)

 saiK.% 

Dixon Sandstone

Geiger's Lake coal bed'

Anvil Rock Sandstone

Mulford Formation

Tf

c E

^

c

Lee (1916)

Geiger Lake coal bed'

Anvil Rock

Sandstone Member

Top of No 11 coal bed'

FIGURE 1. Correlation chart showing the

This report is based in large measure on the areal geological 

mapping of Kentucky being conducted by the U.S. Geological Survey in cooperation with the Kentucky Geological Survey. The 

writer is grateful to the Peabody Coal Co. for releasing heretofore 

unpublished data on cores from the lower part of test holes drilled 

at the type locality of the Sturgis Formation.

PREVIOUS NOMENCLATURE

LISMAN FORMATION

The name Lisman Formation was assigned by Glenn (1912a, p. 

26) to a stratigraphic sequence of Upper Pennsylvania rocks consisting chiefly of soft, partly calcareous shale and some sandstone 

and thin limestone beds between the base of Owen's (1857) Anvil 

Rock Sandstone below and the base of a sandstone, the Dixon 

Sandstone of Glenn (1912a), at the top (fig. 1). Harvey (1956, 

p. 64) redefined the lower boundary as the top of the No. 11 coal 

bed of the Carbondale Formation, and this is now accepted as the 

base of the Sturgis Formation.

In the Kentucky part of the Shawneetown 15-minute quadrangle, rocks stratigraphically equivalent to the Lisman were 

identified by Lee (1916) as the McLeansboro Formation on the 

basis of correlation with the Pennsylvanian coal-bearing sequence 

in Illinois. The term McLeansboro Formation did not find wide 

acceptance in Kentucky and was eventually abandoned (Harvey, 

1956, p. 64) in favor of the Lisman Formation.

A number of subunits of the Lisman Formation were recognized 

by earlier workers. Of these the Providence Limestone, Anvil Rock
STURGIS FORMATION, WESTERN KENTUCKY COAL FIELD B3

nomenclature of this report and of earlier reports.

Sandstone, Madisonville Limestone, and Carthage Limestone are 

retained as members of the Sturgis Formation.

HENSHAW FORMATION

The Henshaw Formation was named by Lee (1916, p. 43) for 

rocks exposed in the vicinity of Henshaw, Union County, Ky., and 

included all strata of Pennsylvanian age above the base of a massive sandstone which occurs a few feet above the Geiger Lake coal 

bed. Lee (1916, p. 43) described the unit as consisting of interbedded sandstone, shale, and coal. Earlier, in nearby Webster 

County, Glenn (1912a) had designated a sequence, almost the 

homotaxial equivalent of the Henshaw, as the Dixon Formation 

and named the basal sandstone the Dixon Sandstone. But because 

the "Dixon" was preoccupied, the entire unit was renamed the 

Henshaw Formation by Lee. As reported by Glenn (1912b, p. 57) 

and as used by Glenn (1922) and Smith and Smith (1967), the 

Dixon Sandstone occurs only a few feet above the Geiger Lake 

coal bed in the Henshaw area.

Seemingly the massive sandstone above the Geiger Lake would 

be equivalent to Glenn's Dixon Sandstone, but this is not so. Geologic mapping and subsurface studies in the area between Dixon, 

Ky., the type locality of the Dixon Sandstone, and Henshaw, Ky. 

(fig. 2) show that the Geiger Lake coal bed of Lee is 60 to 70 feet 

above the Dixon Sandstone of Glenn.

Smith and Smith (1967, p. 11), who were unaware of the miscorrelation, proposed the term "Dixon Sandstone Member of the 

Henshaw Formation" to include the Dixon Sandstone of Glenn
B4 CONTRIBUTIONS TO STRATIGRAPHY

87°30'

37°

30'

V ^. IND \\N, \ 

/- / \

c~ A i Site of \

 Sy/3r Carthage \ 

*^TXA^' settlement 1

^/a l Morganfield1 

|£j UNION > -- ~ ?

\ Henshaw

\Dekoven 2 A 3

\ x /?Sturgis/

^ L-f

I,

/

s

/4 5

' Dixon

o

WEBSTER

/

/^ Provjdenc

0 5 10 MILES >/ i i ... i i '

* -^ Ma

\

\

/

___^/ /'

HOPKINS

6 1

disonville? 7

15-minute quadrangle

1. Shawneetown 

yi^-rninute quadrangles

2. Dekoven

3. Sturgis

4. Bordley

5. Dixon

6. Madisonville West

7. Madisonville East

Locality referred 

to in text

Location of area

FIGURE 2. Index map of part of the western Kentucky coal field showing 

localities and quadrangles referred to in this report.

and the massive sandstone above the Geiger Lake coal bed as 

described by Lee. From Dixon the sandstone appears to extend 

westward at least as far as the east boundary of the Bordley quadrangle (fig. 2) ; it has not been identified in the Henshaw area. 

Its extent in other directions is not known. Because of the foregoing and because the term "Dixon" is preoccupied, the Dixon 

Sandstone Member of Smith and Smith is not proposed as a member of the Sturgis Formation.

STURGIS FORMATION

Subsurface and outcrop data show that rocks previously assigned to the Lisman and Henshaw Formations consist of the 

same lithic types in equal proportion and similar stratigraphic 

distribution; hence, no criteria for differentiating the two units 

for mapping purposes could be found. Therefore, the two formations have been combined to form a new unit, the Sturgis Formation.

The Sturgis Formation is largely concealed by loess, alluvium, 

and colluvium, and no outcrop adequate for a type locality was 

found. Hence, the type area and composite section (fig. 3) of the 

formation is designated as two core holes drilled by the Peabody 

Coal Co. and stratigraphic test hole 1801 drilled by Cities Service 

Oil Co. at Camp Breckinridge about 3 miles northeast of hole
STURGIS FORMATION, WESTERN KENTUCKY COAL FIELD B5

J oJ s

to &o '

IIrj a; 43 03

a ft o
B6 CONTRIBUTIONS TO STRATIGRAPHY

P-49. The core holes, designated P-47 and P-49, are about 5 miles 

northeast of Sturgis, Union County, Ky., and are in the northeast 

part of the Sturgis quadrangle in Carter Coordinate section 21, 

N-19, and section 20, N-19. Hole P-49 is about 1 mile northeast 

of hole P-47 and is about 800 feet northeast of an oil test hole, 

C. E. O'Neal Co. H. M. Shouse 1 dry hole in Carter Coordinate 

section 20, N-19. (See page Bll for additional location data.)

Representative core samples from holes P-47 and P-49 are on 

file at the core library of the Illinois State Geological Survey, 

Urbana, 111. Of the total section represented by the cores, Smith 

and Smith (1967, p. 14-25 and pi. 1) described 1,588 feet which 

they assigned to the Henshaw and Lisman Formations but here is 

reassigned to the Sturgis Formation. They correlated these rocks 

with the electric log of the C. E. O'Neal Co. H. M. Shouse 1 dry 

hole. Sixty feet of section below that described by Smith and 

Smith and also belonging to the Sturgis has been subsequently 

described by W. H. Smith (written commun., 1972) of the Illinois 

State Geological Survey. About 2,075 feet of the Sturgis Formation in a fault block in the Bordley 71/2-minute quadrangle includes 

about 460 feet of stratigraphically higher strata than were described from cores P-47 and P-49. Four hundred and thirty-five 

feet of these younger strata was penetrated by the Cities Service 

Oil Co. stratigraphic test hole Camp Breckinridge 1801, about 3 

miles east-northeast of hole P-49 and about 8 miles northeast of 

Sturgis, Ky. These strata and an additional 25 feet of younger 

strata poorly exposed in a nearby outcrop are proposed as a reference section. Descriptions of samples from the test hole and 

electric-log data are on file at the Kentucky Geological Survey in 

Henderson, Ky.

A modified description of the measured core sections P-47 and 

P-49 and a generalized description of the 460 feet of stratigraphically higher strata penetrated by Cities Service Oil Co. test hole 

1801 is presented on page Bll of this report. The stratigraphic 

relations of these sections are shown in figure 4.

As determined from surface and subsurface investigations, the 

Sturgis Formation is composed of interbedded sandstone, siltstone, 

shale, limestone, and coal. Sandstone, the dominant rock type, 

makes up 30 to 50 percent of the formation. The sandstone is 

commonly light to dark gray, weathering to yellowish brown, and 

is fine to medium grained; locally, near the bottom of some 

channel-fill deposits, it is coarse grained and conglomeratic. Beds 

of sandstone are thin to very thick and massive; crossbedding, 

cut-and-fill structure, and channel deposits are common; some 

channel deposits are as much as 60 feet thick at places. Most of
STURGIS FORMATION, WESTERN KENTUCKY COAL FIELD B7

FORMATION

C/>

O

o:

D 

hC/>

CARBON- L 

DALE

Smith and Smith

(1967, p. 14-25)

p_49 P-47 Cities Serv ce Oil Co., 

(Lower 60 ft from Camp Breckinndge 1801

W. H. Smith, written

commun., 1972)

Outcrop -- 25 ft.

data

34 ft'T Limestone' - 465 ft.

oo7 ft Coal

1,618 ft.-

0!

n

ULS>aLbed _____ 8

"O

*-> 

o 

c

"ra

0!

c

0!

Base of Carthage Limestone Member w

Base of Madisonville 

Limestone Member

Coal Base of Providence

/Limestone Member

Nop of No. 11 coal bed

FEET

i- 500

-

- 0

FIGURE 4. Correlation of measured core sections P-47 and P-49 and of the 

rocks penetrated by the Cities Service Oil Co. stratigraphic test hole Camp 

Breckinridge 1801.

the sandstone is friable to moderately indurated, but locally it is 

well indurated and forms conspicuous cliffs as much as 20 feet 

high. In the west-central part of the western Kentucky coal field 

most hills are commonly capped by sandstone of the Sturgis 

Formation.

Siltstone makes up about 30 to 40 percent of the Sturgis. When 

fresh, the rock is light to dark gray; it weathers to yellowish 

brown or grayish brown. Most siltstone is in even to wavy beds
B8 CONTRIBUTIONS TO STRATIGRAPHY

1/2 to 4 inches thick, but locally the beds appear contorted. The 

siltstone is limy and fossiliferous where it grades into or is interbedded with limestone. The siltstone is generally interbedded with 

or grades laterally into sandstone and shale.

Shale makes up about 20 to 30 percent of the Sturgis. Most of 

the shale is medium gray to black and weathers to yellowish brown 

or yellowish gray. It is poorly to well laminated and generally is 

very micaceous on bedding surfaces. The shale is carbonaceous and 

contains plant fossil fragments where associated with coal beds or 

coaly zones. Marine fossils, chiefly brachiopods and crinoids, are 

common only where the shale is interbedded with limestone. White 

to medium-gray clayey shale is generally present below coal beds 

and coaly zones and locally is interbedded with limestone.

Limestone makes up less than 5 percent of the formation. The 

limestone is generally light to dark gray and weathers light gray 

to yellowish brown. It ranges from very fine to coarse grained but 

is mostly very fine to fine grained and generally is reported as 

"dense" on drill-hole logs. The limestone is mostly in even to wavy 

beds 1/2 to 12 inches thick, but beds as much as 10 feet thick are 

locally present in the Carthage Limestone Member. Fossils, chiefly 

brachiopods and crinoid fragments, are common in many limestone beds.

Coal is generally a minor constituent of the Sturgis Formation. 

Most coal is thin, ranging from very thin laminations to beds 18 

inches thick. However, the Nos. 12, 13, and 14 coal beds are locally 

very thick, and the No. 14 coal bed is reported to be more than 12 

feet thick in some drill-hole logs.

The thickness of the Sturgis Formation represented by the sections at the type locality is 1,678 feet and at the reference section 

is 2,075 feet. In the Sturgis quadrangle, approximately 1 mile west 

of the reference section and in the same fault block, the formation 

is at least 2,650 feet thick (Kehn, unpub. data). The total thickness of the formation is not known because the upper part has 

everywhere been removed by erosion.

PROVIDENCE LIMESTONE MEMBER

The Providence Limestone Member was named by Glenn (1922, 

p. 98) from exposures at Providence, Ky. He described it as occurring between the No. 11 and No. 12 coal beds and as consisting 

of an argillaceous, impure, and irregularly bedded limestone that 

locally contains a shale parting a few inches to a few feet thick. 

Recent studies of numerous drill-hole records in the western 

Kentucky coal field have shown that Glenn's No. 12 coal bed at 

Providence is actually the No. 13 coal bed; therefore the Provi-
STURGIS FORMATION, WESTERN KENTUCKY COAL FIELD B9

dence includes all limestone beds between the No. 11 and No. 13 

coal beds.

In core hole P-47 the Providence Limestone Member comprises 

about 33 feet of strata, extending from the base of the limestone 

bed above the No. 11 coal bed to the top of the limestone bed a few 

feet below the No. 13 coal bed. In the Providence area, Kentucky, 

and elsewhere in the western Kentucky coal field, the member 

includes as many as four limestone beds separated by light- to 

dark-gray clayey shale and, locally, thin lenses of sandstone. At 

places, the No. 12 coal bed, which is generally thin and locally 

discontinuous, occurs just above the lowest limestone bed. The 

Providence Limestone Member is poorly exposed except in highwalls of strip mines on the No. 11 coal bed.

ANVIL ROCK SANDSTONE MEMBER

The Anvil Rock Sandstone was named by Owen (1856, p. 45) 

for a massive-bedded sandstone exposed in a bluff known as Anvil 

Rock west of Dekoven, Ky. The unit was later formally given the 

rank of member and assigned to the Lisrnan Formation by Harvey 

(1956, p. 65). It consists of reddish-brown to yellowish-brown 

crossbedded fine- to coarse-grained sandstone that contains a few 

white quartz pebbles as much as 14 inch in diameter. At Anvil 

Rock the sandstone rests unconformably on the No. 11 coal bed, 

and the lower 2 to 3 feet consists of a residuum of shale chips and 

coarse sand in an "earthy" limonitic matrix. The Anvil Rock 

Sandstone Member has a maximum thickness of about 110 feet in 

the Dekoven quadrangle where it was deposited in a channel that 

had a steep west bank and a gentle east bank. Channel-fill sandstone deposits of the Anvil Rock Sandstone Member have been 

reported by Harvey (1956), Hopkins (1958), and Potter and 

Simon (1961). Hopkins (1958) recognized a thin widespread 

"sheet phase" of the Anvil Rock in southern Illinois and parts of 

southern Indiana and western Kentucky. In the Dekoven quadrangle Kehn (1973) restricts the name Anvil Rock Sandstone 

Member to the channel-fill deposit entirely within the bounds of 

the quadrangle; other relatively thin, lenticular sandstones in 

about the same stratigraphic interval may or may not be timestratigraphic or homotaxial equivalents.

MADISONVILLE LIMESTONE MEMBER

The Madisonville Limestone Member was named by Norwood 

(1878, p. 319-320) for exposures in Madisonville, Hopkins County, 

Ky. He reported about 4 feet of massive light-brown to light-gray 

fossiliferous limestone about 80 feet above the No. 11 coal bed. The
BIO CONTRIBUTIONS TO STRATIGRAPHY

name was adopted by the U.S. Geological Survey (Harvey, 1956) 

as the Madisonville Limestone Member of the Lisman Formation.

In the type area the member includes limestone, claystone, shale, 

sandstone, and coal (Kehn, 1963 and 1964). The limestone is light 

to medium gray, very finely to coarsely crystalline, and locally 

fossiliferous (mostly brachiopods and crinoid plates). Weathered 

surfaces are light brown to light gray. Claystone is light to 

medium gray and locally contains small nodules of hematite. Shale 

is light gray to black and is locally coaly. Sandstone is fine to 

medium grained, micaceous, and thin to thick bedded. In the 

vicinity of Madisonville the member is about 200 feet above the 

base of the Sturgis Formation, rather than 80 feet as reported by 

Norwood, is as much as 50 feet thick, and contains as many as 

four limestone beds that range in thickness from 0 to 5 feet (Kehn, 

1963 and 1964). In core hole P-47 only one bed of limestone is 

present. The Madisonville Limestone Member is generally poorly 

exposed owing to a cover by surficial deposits. Best exposures are 

in highwalls of strip mines on the No. 14 coal bed.

CARTHAGE LIMESTONE MEMBER

The Carthage Limestone was named by Owen (1856, p. 60-61) 

for exposures on the bank of the Ohio River at the site of Carthage 

settlement, about 1 mile below Uniontown, Union County, Ky. The 

unit was proposed as the Carthage Limestone Member of the Lisman Formation by Smith and Smith (1967).

The member generally ranges from 2 to 5 feet in thickness, but 

in some drill-hole logs it is reported to be as much as 10 feet thick. 

It commonly consists of one bed, but on a few logs it is reported 

as two limestone beds. The limestone is regionally persistent but 

locally is absent owing to nondeposition or erosion. Owing to 

weathering and thinness, the bed is seldom seen on outcrop. In 

core hole P-47 the member is about 465 feet above the base of the 

Sturgis Formation.

CONTACTS

The Sturgis Formation overlies the Carbondale Formation 

(Middle Pennsylvanian) with which it intergrades. The Carbondale, as is the Sturgis, is composed of interbedded sandstone, siltstone, shale, limestone, and coal, but in general limestone beds of 

the Carbondale are fewer and thinner and have smaller areal extent, and coal beds are more numerous and thicker and have 

greater areal extent.

The zone of intergradation between the two units is wide and
STURGIS FORMATION, WESTERN KENTUCKY COAL FIELD Bll

because of poor exposure is difficult to locate. Hence, for convenience of mapping, the contact is placed at the base of the Providence Limestone Member, which at some places rests directly on 

the No. 11 coal bed of the Carbondale Formation but at other 

places is as much as 5 feet above the No. 11. The Providence and 

the No. 11 coal bed in close proximity form a zone that is easily 

recognized. Recognition is further facilitated by the presence of 

a persistent thin shale parting, commonly referred to as the blue 

band, in the lower half of the No. 11 coal bed.

The upper limit of the Sturgis Formation is not defined because 

the upper part of the formation has everywhere been removed by 

erosion.

LOCATION OF DRILL HOLES

(fig. 3)

Hole P-47, 200 ft from N. line and 2,300 ft from W. line of Carter Coordinate 

section 21, N-19, or 9,350 ft from north boundary and 14,650 ft from east 

boundary of the Sturgis 7 1/2-minute quadrangle, Union County, Ky. Surface 

elevation 375 ft above mean sea level.

Hole P-49, 1,800 ft from N. line and 600 ft from E. line of Carter Coordinate 

section 20, N-19, or 4,900 ft from north boundary and 12,700 ft from east 

boundary of Sturgis 7%-minute quadrangle, Union County, Ky. Surface 

elevation 410 ft above mean sea level.

Oil test hole C. E. O'Neal Co. H. M. Shouse 1 dry hole, 2,300 ft from N. 

line and 1,100 ft from E. line of Carter Coordinate section 20, N-19, or 

5,450 ft from north boundary and 13,200 ft from east boundary of Sturgis 

7%-minute quadrangle, Union County, Ky. Surface elevation 413 ft above 

mean sea level. Electric-log datum 415 ft above mean sea level.

Stratigraphic test hole Cities Service Oil Co. stratigraphic test hole Camp 

Breckinridge 1801, 700 ft from S. line and 600 ft from W. line of Carter 

Coordinate section 12, N-20, or 2,150 ft from north boundary and 3,150 ft 

from west boundary of Bordley 7%-minute quadrangle, Union and Webster 

Counties, Ky. Surface elevation 520 ft above mean sea level. Driller's log 

and mechanical electric-log datum 526 ft above mean sea level.

SECTIONS OF THE STURGIS FORMATION

UPPER SECTION

This section includes 460 feet of strata younger than that described from core holes P-47 and P-49. Lithologies are based on 

descriptions of samples from Cities Service Oil Co. stratigraphic 

test hole Camp Breckinridge 1801 and on outcrop data.

Pennsylvanian System Sturgis Formation (in part): D(f&et) 

Surface, includes loess, soil, and weathered bedrock _ _ 0-5 

Sandstone and siltstone, micaceous, weathered; very poorly

exposed; reported as siltstone in sample log __ ___ 5-65 

Siltstone and sandstone, micaceous ________________ 65-119
B12 CONTRIBUTIONS TO STRATIGRAPHY

c'D'

Pennsylvania!! System Sturgis Formation (in part) Continued (feet) 

Limestone, brown, dense _____________________ 119-121 

Shale, medium-gray ____________________" __ 121-133 

Limestone, brown, dense _______________________ 133-137 

Shale, dark-gray to brown _____________________ 137-146 

Sandstone, light-gray, very fine grained, micaceous ____ 146-158 

Shale, dark-gray, silty, locally carbonaceous ____-__-_- 158-185 

Coal and carbonaceous shale ____________________ 185-186 

Sandstone, light-gray, very fine grained, silty and shaly 186-197 

Shale and siltstone, light- to dark-gray, micaceous, sandy;

shale locally coaly _________________________ 197-226 

Sandstone, light-gray, very fine grained, micaceous; includes

some thin beds of shale and siltstone ______- 226-260 

Shale, medium-gray to black, coaly. Coal prospect pits about

1,500 feet southeast of well site caved, estimated thickness

2 ft. Probably correlative to coal, near base, of this unit _ 260-270 

Limestone, tan, finely crystalline, dense ______ 270-275 

Shale and siltstone, light- to dark-gray, micaceous; thin bed

of limestone reported in middle of unit ____- - 275-315 

Limestone, brown, dense ______________________ 315-320

Shale and siltstone, light- to dark-gray ___________ 320-340 

Sandstone, white, very fine grained _________________ 340-345

Shale and siltstone, light- to dark-gray, micaceous; shale

contains siderite pellets ___________- ____ 345 375

Coal and carbonaceous shale ___________-_____ 375-400

Shale and siltstone, light- to dark-gray, micaceous _____ 400-425

Sandstone, light-gray, very fine grained _____________ 425-438 

Siltstone and shale, medium-gray to black, carbonaceous at

base ___________________________________ 438-460 

Limestone, light-gray, dense (stratigraphically equivalent to

limestone at about 31 to 34 ft in core hole P-49 (Smith

and Smith, 1967, p. 14; fig. 4, this report)) _______ 460-465

MIDDLE SECTION

A modified log description of about 1,638 feet of the Sturgis 

Formation penetrated by holes P-47 and P-49 of the Peabody 

Coal Co. has been made from the detailed log descriptions by 

Smith and Smith (1967, p. 14-25). The description from 0 to 387 

feet is from the core description of hole P-49, and that from 387 

to 1,618 feet is from the core description of hole P-47.

Pennsylvanian System Sturgis Formation (in part) :

No data, started to core at depth of 30 ft _________-__

Shale, medium-gray, slightly silty, calcareous, ostracodes, 

carbonized plant fragments ________________

Limestone, medium-gray at top and light-olive-gray at base, 

dense; about 1 ft silty fossiliferous medium-gray shale 3 

in. below top; unit is stratigraphically equivalent to that

Depth 

(feet)

0-30 

30-31
STURGIS FORMATION, WESTERN KENTUCKY COAL FIELD B13

Pennsylvanian System Sturgis Formation (in part) Continued D(feet) 

between depths of 435 and 440 ft (labeled 465 ft on fig. 4) 

in the Cities Service test hole ______________--- 31-34

Claystone, medium-gray, slightly silty, relatively hard but 

crumbly; scattered limestone nodules as much as 2 in. 

thick; carbonaceous shale near top and base _________ 34-39

Limestone, light-olive-gray to medium-gray; argillaceous,

dense; contains greenish-gray clay matrix ________ 39-49

Claystone, light-greenish-gray, very soft, crumbly; abundant limestone nodules ____________________ 49-56

Siltstone, light-greenish-gray, slightly argillaceous; calcareous nodule zone 3 ft below top ________________ 56-63

Sandstone, light-gray, fine-grained, in beds mostly 6 in. to 

2 ft thick; bottom 10 ft coarser and contains carbonaceous 

micaceous laminae on bedding planes; in sharp contact 

with 4-in.-thick coal bed at base __-___________ 63-93

Claystone, medium-gray, very friable __________-- 93-95

Siltstone, medium-light-gray; about 50 percent interbedded 

light-gray sandstone _____________________ 95-98

Sandstone, light-gray, fine- to medium-grained, in beds as 

much as 2 ft thick; thin irregular coaly laminae and scattered coaly bands as much as % in. thick __ ____ _ 98-152

Claystone, medium-gray, silty; small dark limestone nodules

in lower part; 7-in.-thick coal bed at top ___________ 152-156

Siltstone, medium-gray, argillaceous, hackly fracture; scattered limestone nodules ___________________ 156-164

Sandstone, light-gray, fine-grained, interbedded with about

30 percent siltstone similar to above ___________ 164-167

Shale, medium-dark-gray, clayey to silty; brownish-orange

sideritic veinlets and crack fillings ______________ 167-169

Shale, brownish-orange, silty, poorly bedded; sideritic veinlets and crack fillings _______________________ 169-170

Sandstone, light-gray, thinly laminated; scattered calcareous nodules _____________________________ 170-171

Siltstone, medium-gray, fairly well laminated ________ 171-172

Claystone, medium-gray, very soft; abundant small limestone pellets, granular siderite, and scattered dark sideritic masses _____________________________ 172-176

Siltstone, medium-gray, slight greenish-gray cast, poorly

bedded; argillaceous; limestone nodules _________ 176-183

Sandstone, light-gray, fine-grained, and about 30 percent

interlaminated siltstone, as above _____________ 183-185

Shale, medium-gray, thinly laminated; medium-gray siltstone at base _____________________________ 185-188

Limestone, light-olive-gray to medium-dark-gray; greenishgray claystone matrix; massively bedded, hard, dense; 

fossiliferous, contains brachiopods, pelecypods, crinoids _ 188-193

Shale, medium-dark-gray, very silty, well-laminated _ ___ 193-194

Siltstone, medium-dark-gray; contains laminae and lenses 

of fine-grained, light-gray sandstone _____________ 194-200
B14 CONTRIBUTIONS TO STRATIGRAPHY

Pennsylvanian System Sturgis Formation (in part) Continued

Siltstone, medium-gray; thinly interbedded and interlaminated with medium-dark-gray shale; scattered interlaminations of fine-grained, light-gray sandstone _______ 200-220

Shale, medium-gray; interbedded with shaly siltstone and 

scattered interlaminations of fine-grained, light-gray 

sandstone _______________________________ 220-244

Shale, medium- to dark-gray, fissile ___________-_ 244-255

Limestone, medium-gray, very fossiliferous, contains brachiopods, crinoids, and 50 percent interbedded dark-gray 

shale __________________________________ 255-258

Claystone, medium-gray, very crumbly; small limestone nodules in lower 1 ft __________________________ 258-262

Limestone, medium-gray, brecciated; traversed by calcite 

veinlets _________________________________ 262-263

Claystone, medium-gray, few limestone and sideritic nodules, 

poorly bedded; bottom 3 in. contains argillaceous limestone and siderite nodules _________________-_- 263-270

Shale, medium-gray, fissile; several dark-gray carbonaceous

laminae in bottom 1 ft with l^-in.-thick coal bed at base 270-281

Claystone, medium-dark-gray, hard, pyritic, slightly silty;

contains poorly preserved plant rootlets at top 281-283

Claystone, greenish-gray; top 1 ft limy almost a very argillaceous limestone; contains small granules and scattered nodules of light- to medium-gray limestone __ 283-287

Siltstone, medium-gray, argillaceous; contains nodules, 

masses, and veinlets of brownish-gray limestone and siderite __________________________________ 287-290

Sandstone, light-gray, fine-grained, and 35 percent thinly

laminated shale ________________________ 290-295

Shale, medium- to dark-gray; few siderite nodules; thin 

beds of fine-grained sandstone ________-_ 295-329

Limestone, medium-gray, shaly, very fossiliferous with

brachiopods, crinoids, corals __________ -- 329-331

Shale, black, fissile, hard; 4-in.-thick coal bed at base ___ 331-333

Shale, medium- to dark-gray; abundant carbonized plant

stem impressions; silty toward base 333-335

Sandstone, light-gray, fine-grained, and interbedded with 

about 10 percent siltstone; contains coal shale in lowest 

1 ft ___________________________________ 335-345

Siltstone, medium-gray; interlaminations of sandstone _ 345 350

Shale, medium-dark-gray, laminated; scattered siderite nodules and lenses __________________________ 350-370

Shale, medium-dark-gray, very fissile; abundant siderite 

bands and nodules _______________________ 370-386

Shale, medium-dark-gray; very fossiliferous, contains numerous pectinaceans. Coal bed, 2% in. thick, at base is 

stratigraphic equivalent of 2%-in.-thick coal at depth of 

67 ft 9^ in. of core P-47, described by Smith and Smith 

(1967, p. 17) ___________________________ 386-387
STURGIS FORMATION, WESTERN KENTUCKY COAL FIELD B15

Pennsylvania!! System Sturgis Formation (in part) Continued (feet) 

Claystone and shale, medium-gray, carbonaceous, very silty

in part _______________________________ 387-389 

Limestone interbedded with about 30 percent shale; limestone, light-olive-gray to yellowish-gray, is light brownish 

gray in middle and at base; dense; abundant ostracodes 

throughout. Shale, medium-gray, silty, very clayey, calcareous ___________________________________ 389-392 

Claystone, medium-gray, calcareous; silty in lower part - 392-395 

Siltstone, light-gray, very calcareous throughout, thinly

laminated; thin partings of shale ______-__ ___ 395-400 

Shale, medium-gray, very silty in top 1 ft, becomes slightly 

silty with depth, well-laminated; carbonized plant fragments _________________________________ 400-410 

Shale, medium-dark-gray, smooth, fissile ___________ 410-411 

Coal, bright, banded ________________________ 411-412 

Shale, medium-dark-gray, clayey to silty, scattered carbonized plant impressions ____________________ 412-415

Siltstone, light- to medium-gray __________________ 415-416 

Shale, medium-gray; conspicuous carbonized plant impressions, numerous ostracodes; thin coal laminae in top 1 ft _ 416-427 

Siltstone, light-gray, and about 20 percent thin interlaminations of silty medium- and dark-gray shale __________ 427-431

Sandstone, light-gray, fine-grained, thick-bedded, crossbedded in zones; abundant coarse mica and carbonaceous 

debris on bedding planes; a few %- to 3-in.-thick beds of 

siltstone in top 5 ft; ^-in.-thick coal bed at base ____ 431-450 

Sandstone, medium- to fine-grained; abundant coarse mica _ 450-454 

Sandstone, fine-grained; top 1 ft contains a few sideritic 

lenses and pebbles; %-in.-thick coaly band 1 ft above 

base; several %-in.-thick shale lenses scattered throughout ___________________________________ 454-472 

Sandstone, light-gray, fine-grained, very thinly and irregularly interlaminated with about 15 percent mediumdark-gray shale and siltstone ________________ 472-481

Shale, medium-dark-gray, hard; thin interlaminations of

light-gray siltstone ________________________ 481-488 

Shale, dark-gray; numerous fossils including brachiopods 

and pelecypods; contains three l-in.-thick fossiliferous 

limestone lenses ___________________________ 488-492 

Shale, dark-gray, fissile _______________________ 492-495 

Claystone, medium-gray, highly calcareous; contains abundant pellets and small nodules of very light gray limestone; 2^-in.-thick light-gray limestone bed at top _____ 495-505

Siltstone, light-gray, calcareous, thinly laminated with about

15 percent medium-gray shale ________________ 505-511

Shale, medium-gray, interlaminated with siltstone _______ 511-525

Shale, dark-gray, clayey, laminated, thin lenses and nodules 

of siderite; lower 3 ft contains scattered pelecypods and 

ostracodes ______________________________ 525-530
B16 CONTRIBUTIONS TO STRATIGRAPHY

Pennsylvanian System Sturgis Formation (in part) Continued (feet)

Coal, bright, banded ________________________ 530-531

Claystone, medium-dark-gray, very crumbly; calcareous and 

contains limestone pellets _____________ _ 531-534

Siltstone, light-gray, clayey and calcareous, moderately 

hard, some interbedded shale in lower part _ 534-539

Claystone, light-gray, silty, faintly laminated; siderite in

veinlets; 3-in.-thick carbonaceous shale bed at base ____ 539-541

Siltstone, light-gray, and 10 to 20 percent interlaminated 

medium-gray shale; siderite nodules and veinlets ____ 541-553

Sandstone, light-gray, fine-grained; top 5 ft thick bedded; 

lower part thin bedded and interbedded with siltstone -__ 553-562

Siltstone, medium-gray ______________________ 562-570

Shale, medium-dark-gray, silty at top; moderately hard, well 

laminated, siderite streaks in lower part; lower 2 ft contains scattered pelecypods, ostracodes, and fish scales; 

8^-in.-thick coal bed at base _________________ 570-574

Shale, medium-dark-gray, with interlaminations of siltstone ________________________________ 574-576

Siltstone, medium-gray, and interbedded fine-grained, lightgray sandstone ____________________ _ 576-581

Shale, medium-gray, medium-gray siltstone, and light-gray 

sandstone; irregularly and thinly interbedded in about 

equal amounts ___________________________- 581-586

Siltstone, medium-gray, and light-gray sandstone, irregularly interbedded ________________________ 586-597

Shale, medium-dark-gray, slightly silty, relatively hard, 

well-laminated __________________________ 597-602

Limestone, abundant white pellets and irregular limestone

masses in dark-gray claystone matrix; fossiliferous ____ 602 603

Claystone, medium-gray, crumbly; white limestone nodules

at base _______________________________ 603-604

Siltstone, light-gray, rather soft; argillaceous; calcareous in 

top 3 ft, well bedded, thinly laminated; lower part contains about 50 percent fine-grained, light-gray sandstone _ 604-624

Siltstone, medium-gray, with about 10 percent thin interlaminations of light-gray, fine-grained sandstone _ 624-631

Siltstone, medium-gray, and thinly interlaminated lightgray sandstone, in about equal proportions _______ __ 631-657

Sandstone, fine-grained, in beds 3 to 8 in. thick; sharp contact with underlying coal ___________________ 657-665

Coal (Geiger Lake coal bed), bright, somewhat bony to 

shaly __________________________________ 665-666

Claystone, medium-gray, moderately hard; few carbonized 

plant impressions; small white limestone nodules in lower 

part ___________________________________ 666-669

Limestone, light-gray, hard, dense; sublithographic to finely 

crystalline texture; contains a few clay bands in lowest 

10 in. _________________________________ 669-672
STURGIS FORMATION, WESTERN KENTUCKY COAL FIELD BIT

Pennsylvania!! System Sturgis Formation (in part) Continued (feet)

Claystone, medium-gray with greenish cast, very crumbly; 

weak shaly bedding; contains much siderite as granules 

and veinlets _____________________________ 672-675

Shale, medium-gray, slightly silty, relatively hard; contains

a few thin beds of siltstone ___________---__- 675-684

Shale, medium-dark-gray, well-laminated ______-_-_- 684-694

Shale, medium-gray, slightly silty throughout, well-laminated, 

uniform; from 704 to 708 ft silty beds as much as 8 in. 

thick, contain slump structures _______________ 694-728

Shale, dark-gray to black; sideritic bands; marine fossils; 

l%-in.-thick coal bed and coaly shale, 7 in. above base, 

and l^-in.-thick coal bed and coaly shale at base -___- 728-733

Claystone, medium-gray, very smooth, slickensides; abundant well-preserved plant impressions ____-_-_-__- 733-734

Siltstone, medium-gray; contains poorly preserved root impressions and coprolites __________________ 734-735

Siltstone, medium-gray, in fairly uniform beds ¥2 to 2 in. 

thick ________________________________ 735-738

Sandstone, light-gray, fine-grained, in beds as much as 2 ft

thick; some laminae of medium-gray shale or siltstone ___ 738-770

Siltstone, medium-gray, shaly; several 1- to 3-in.-thick 

sandstone beds, a few sandstone- and shale-pebble conglomerate beds that contain coaly bands __________ 770-774

Shale, medium-gray, relatively clayey, fairly soft; bedding

inclined about 30°; angular unconformity at base _____ 774-776

Sandstone, light- to medium-gray, fine-grained; l-in.-thick

zone at base contains pebbles and lenses of shale _____ 776-777

Shale, medium-dark-gray to black, carbonaceous _________ 777-778

Coal, bright, banded ________________________ 778-779

Shale, medium-gray, hard, clayey, moderately laminated;

19-in.-thick coal bed and coaly shale at base ___ ___ 779-783

Sandstone, dark-gray, fine-grained; carbonaceous, argillaceous, light-gray and calcareous in bottom 4 in _______ 783-784

Claystone, very faintly laminated, silty; abundant pellets 

and irregular masses of light- to dark-gray limestone as 

much as 1 in. in diameter _______________ ___ 784-787

Siltstone, very argillaceous, calcareous; pellets and irregular 

masses of light- to dark-gray limestone constitute about 

10 percent of unit _________________________ 787-790

Coal, bony; 5 in. of medium-gray to black shale at top ___ 790-791

Claystone, medium-gray, very calcareous, crumbly; at base, 

6 in. of very argillaceous light-gray limestone containing 

darker gray nodules ________________________ 791-798

Claystone, silty; moderately soft, faintly laminated; moderately abundant granular siderite and some finely disseminated pyrite __________________________ 798-804

Limestone, light-gray, very impure; very silty in lower part,

shaly near top ____________________________ 804-805
B18 CONTRIBUTIONS TO STRATIGRAPHY

Pennsylvania!! System Sturgis Formation (in part) Continued

Sandstone, light-gray, very fine grained, calcareous, and

irregular thin beds of medium-gray siltstone 805-808

Shale, siltstone, and sandstone, interlaminated; mediumgray shale is about 50 percent of unit ________ _ 808-812

Siltstone, medium-dark-gray, shaly; contains moderately 

abundant plant impressions, carbonaceous debris, and 

coal bands in bottom 8 in. ____________ _ _ 812-814

Claystone, medium-gray, silty, poorly bedded __ - 814-815

Siltstone, medium-dark-gray, and shale, medium-dark-gray; 

interbedded and interlaminated _-__ - 815-824

Shale, medium-dark-gray, silty at top, becomes more clayey 

with depth, relatively hard, well-laminated; widely scattered pelecypods ________________ - - 824-856

Limestone, light-olive-gray, dense, hard, highly fossiliferous; siltstone conglomerate at base ____-___ 856-857

Siltstone, medium-gray, and medium-gray shale, thinly interlaminated; contains abundant granular siderite; bottom 1 % ft interlaminated with about 50 percent light-gray 

sandstone _____________________________- 857-861

Sandstone, light-gray, fine-grained, in beds 8 to 12 in. thick;

a few shale laminae ___________________ _ 861-874

Shale, dark-gray; bottom 2 ft is well laminated; top part

contains about 10 percent light-gray siltstone 874-882

Limestone, light-olive-gray, fossiliferous, crinoidal, somewhat sandy; a single bed in sharp contact with shale 

below _______________________________ 882-885

Shale, dark-gray, well-laminated; contains thin interlaminations of light-gray siltstone; 50 percent siltstone in lower 

1 ft; 8-in.-thick fossiliferous shale and siderite nodule and 

shale-pebble conglomerate about 6 ft below top 885-897

Sandstone, light-gray, fine-grained, irregularly interbedded

with about 25 percent siltstone _________________ 897-909

Siltstone, medium-gray, in beds 6 in. to 2 ft thick 909-914

Siltstone, similar to above; beds of shale 4 in. to 1 ft thick _ 914-924

Shale, medium-dark-gray; medium-gray siltstone in 4- to

18-in.-thiick beds make up about 25 percent of unit _____ 924-944

Shale, medium-dark-gray, and 10 to 20 percent interlaminated light-gray siltstone _____ _ 944-1,015

Shale, grayish-black, smooth, hard, fissile; few siderite nodules; fossiliferous, contains pectinaceans and ostracodes _ 1,015-1,021

Shale, dark-gray; abundant shell fragments _____ _ 1,021-1,023

Claystone, light-gray, crumbly; contains small limestone 

pellets in lower 1 ft; 6 in. bright banded coal at top of 

unit (Lisman coal bed) ____________________ 1,023-1,025

Limestone, medium-gray to grayish-yellow with darker gray 

pellets and nodules; 50 percent light-gray claystone in top 

8 in. ___________________________________ 1,025-1,027

Claystone, medium-gray, crumbly; contains limestone pellets 

and nodules; grades into very clayey, calcareous, sideritic, medium-gray siltstone _______ _ ____ 1,027-1,030
STURGIS FORMATION, WESTERN KENTUCKY COAL FIELD B19

Pennsylvanian System Sturgis Formation (in part) Continued

Sandstone, light-gray, very fine grained, calcareous; about

10 percent siltstone ______________________ 1,030-1,033

Sandstone, siltstone, and shale, irregularly interbedded; 

sandstone, light-gray, very fine grained; siltstone, medium-gray; shale, medium-dark-gray; upper part is principally sandstone and siltstone ________________ 1,033-1,064

Shale, medium-dark-gray, very silty, and about 20 percent 

laminae of siltstone and light-gray sandstone ______ 1,064-1,101

Claystone, medium-gray, crumbly, and grainy; a few very 

small limestone pellets; 3-in. medium-gray shale at base; 

2-in. bright coal at top _____________________ 1,101-1,107

Limestone, grayish-yellow; about 50 percent shale in lower 

4 in ___________________________________ 1,107-1,108

Shale, medium-gray, silty, relatively soft; contains several 

thin beds of siltstone and light-gray, calcareous, finegrained sandstone ________________________ 1,108-1,111

Shale, medium-dark-gray, clayey, fissile; a few siderite 

bands _______________________________ 1,111-1,113

Shale, siltstone, and sandstone, interlaminated ; mostly 

medium-dark-gray shale with lenses and thin beds of 

light-gray, very fine grained sandstone and medium-gray 

siltstone ________________________________ 1,113-1,134

Shale, dark-gray, clayey, fissile __________________ 1,134-1,136

Coal (No. 18 coal bed), bright, banded; shaly zone 2 to 4 in. 

below top _______________________________ 1,136-1,137

Claystone, medium-gray, chippy, and crumbly _______ _ 1,137-1,138

Shale, medium-gray, silty, with laminae and thin beds of 

siltstone; top 1 ft very soft and clayey; contains siderite 

bands and lenses __________________ - ___ -_ 1,138-1,146

Shale, medium-dark-gray, slightly silty, fissile, strongly 

jointed; a conspicuous 2-in.-thick fossiliferous clay or 

ironstone band containing crinoids and shell fossils 11 in. 

above base; a few minute fossils were observed in the 

shale above and below the more fossiliferous band _ _ _ _ 1,146-1,153

Coal, bright, banded ________________________ 1,153-1,154

Claystone, medium-gray, silty; scattered limestone nodules; 

about 8 in. of very argillaceous medium-gray and grayishyellow limestone 1 ft below top _ ____ _ _ _ _ _ __ _ - 1,154-1,157

Siltstone, medium-gray; laminae and a few thin beds of 

light-gray, very fine grained sandstone; top 5 ft contains 

a few shaly zones and is argillaceous and soft near top __ 1,157-1,176

Sandstone, light-gray, fine-grained, in beds mostly 2 to 6 in. 

thick; minor amounts of shale in streaks and thin laminae; contains a %-in.-thick coaly band at 1,183 ft and 

carbonaceous and coaly laminae in a 3-in. -thick zone at 

1,197 ft ________________________________ 1,176-1,205

Shale, medium-gray, silty, well-laminated; no fossils observed; sharp contact with limestone below - 1,205-1,206

Limestone (Carthage Limestone Member), light-olive-gray, 

very dense, wavy bedding; fossiliferous, abundant con-
B20 CONTRIBUTIONS TO STRATIGRAPHY

Pennsylvania!! System Sturgis Formation (in part) Continued 

spicuous crinoid stem segments; top 3 in. a conglomerate 

of shells and siderite nodules in a dark-gray shale 

matrix ________________________________ 1,206-1,213

Shale, dark-gray, dense, fissile __________________ 1,213-1,215

Coal (No. 17 coal bed), bright, banded; coal fragments as 

much as % in. thick were recovered. Driller's log reports 

12 in. of coal _____________________________ 1,215-1,216

Claystone, medium-gray, crumbly; limestone pellets and

nodules as much as 1 in. in diameter in basal 1 ft ____ 1,216-1,219

Claystone, siltstone, and limestone; top 4 in., a 4-in.-thick 

zone near the middle, and the bottom 3 in. are mediumgray to grayish-yellow nodular limestone containing a 

lacelike network of calcite crack fillings with about 25 

percent claystone matrix; remainder of unit is claystone 

and siltstone with minor amounts of limestone _____ 1,219-1,224

Sandstone and siltstone, light-gray, and shale, medium-gray, 

interbedded and interlaminated; upper 6 ft is about 50 

percent sandstone and 50 percent siltstone; lower part is 

30 percent sandstone and 70 percent shale __________ 1,224-1,234

Shale, medium-gray; silty at top, abundant laminae of lightgray siltstone; becomes finer and more fissile downward _ 1,234-1,241

Shale, medium-dark-gray, relatively smooth, thinly laminated; siderite bands and nodules _____________ 1,241-1,244

Shale, dark-gray, very thinly laminated; contains scattered 

pelecypods and ostracodes _____________-____ 1,244-1,250

Coal (No. 16 coal bed), somewhat shaly, bright, banded; no

underclay or seat earth at base of coal _____________ 1,250-1,251

Sandstone, light-gray, very fine grained, thinly interlaminated with about 50 percent medium-gray siltstone and 

medium-dark-gray shale _____________-______ 1,251-1,262

Siltstone, medium-gray, and medium-dark-gray shale; about 

5 to 10 percent light-gray sandstone laminae; more shaly 

in lower part ____________________________ 1,262-1,284

Shale, medium-dark-gray, silty in upper part, well-laminated; becomes finer grained and darker downward; scattered fossils in lower part ________ _ 1,284-1,315

Shale, medium-dark-gray to black; dense; small fossils,

some pyritized; very limy at top __ _________ 1,315-1,324

Shale, medium-dark-gray, silty; sparingly fossiliferous _ 1,324-1,331

Claystone, medium-gray, crumbly; small limestone pellets - 1,331-1,332

Limestone and claystone, medium-gray; claystone contains 

nodules and nodular beds of medium-dark-gray limestone 

as much as 2 in. thick and grayish-yellow lacelike crack 

fillings ________________________________ 1,332-1,334

Shale, medium-gray, clayey, laminated; no fossils observed;

some siderite nodules _____________----_-______ 1,334-1,337

Shale, medium-gray, clayey, laminated; abundant finely disseminated carbonaceous debris _____ __ _ 1,337-1,338

Claystone, medium-dark-gray, silty, relatively hard; suggestive of underclay but Stigmaria not observed ______ 1,338-1,339
STURGIS FORMATION, WESTERN KENTUCKY COAL FIELD B21 

Pennsylvanian System Sturgis Formation (in part) Continued ?/»** (feet)

Shale, medium-gray, and about 25 percent laminae of lightgray siltstone and very fine grained sandstone ______ 1,339-1,352

Siltstone, medium-gray; approaches a very silty claystone _ 1,352-1,353

Shale and siltstone, medium-gray, and light-gray sandstone; 

irregularly interbedded and interlaminated; some contorted bedding ___________________________ 1,353-1,356

Sandstone, light-gray, calcareous, conglomeratic; shale and 

siderite in irregular tongues and lenses; contorted bedding; upper part contains a few brachiopods and fossil 

fragments ______________________________ 1,356-1,359

Sandstone, light-gray, medium-gray siltstone, and about 25 

percent shale, very irregularly interbedded and contorted; 

numerous siderite nodules ____________________ 1,359-1,369

Shale, medium-gray; siderite bands and lenses ____ 1,369-1,384

Limestone, medium-gray, fine-grained, dense; abundant carbonized plant fragments; no fossils discernible; sharp 

contacts at top and bottom ___________________ 1,384-1,386

Shale, medium-gray; in middle part is medium dark gray 

and less silty and contains siderite nodules; bottom 10 to 

15 ft is slightly darker, more thinly laminated, and clayey, 

with a few small pelecypods; 15 percent of top 10 ft is 

light-gray siltstone laminae _____________ __ 1,386-1,445

Limestone, medium-dark-gray, very argillaceous; very fossiliferous, contains brachiopods, corals; 6-in. laminated, 

hard, fossiliferous black shale in middle of unit ___ --- 1,445-1,446

Claystone and coal (No. 15 coal bed), bright, banded; contains shale lenses and marine fossils in top 2 in.; 18-in. 

silty, medium-gray, claystone at base _______ ____ 1,446-1,448

Siltstone, very argillaceous, soft, crumbly; contains nodules 

of freshwater limestone; no discernible bedding in top 

2 ft ___________________________________ 1,448-1,452

Shale, medium-dark-gray, and medium-gray siltstone, interlaminated; a few nodules of limestone _ __________ 1,452-1,454

Shale, medium-dark-gray, silty; a few laminae of light-gray 

sandstone __________________________-____ 1,454-1,467

Sandstone, light-gray, medium- to fine-grained; in beds */4 

in. to 2 ft thick parted by dark, shaly laminae; sharp 

angular unconformity at base with some carbonaceous 

debris ________________________________ 1,467-1,488

Shale, medium-dark-gray, slightly silty, hard, well-laminated; less silty and thinner laminated in lower part, 

fossils in bottom 3 ft ______________________ 1,488-1,492

Limestone (Madisonville Limestone Member), medium-gray; 

a single massive bed; dense; abundant fossils; calcitefilled vertical fractures _____________________ 1,492-1,497

Claystone, medium-gray, relatively hard, finely disseminated 

pyrite and siderite granules; very carbonaceous in top 

2 in. __________________________________ 1,497-1,498

Siltstone, medium-gray, interlaminated with about 25 percent sandstone ___________________________ 1,498-1,500
B22 CONTRIBUTIONS TO STRATIGRAPHY

Pennsylvania!! System Sturgis Formation (in part) Continued

Sandstone, light-gray, fine-grained; shaly laminae _____ 1,500-1,506 

Sandstone, light-gray and medium-gray; shale and siltstone, 

regularly interl animated ______ - ___ ____ 1,506-1,512

Sandstone, light-gray above, medium-gray below _ _____ _ 1,512-1,514 

Siltstone, medium-gray __________ _ _ _ _ ______ 1,514-1,524

Shale, medium-gray, medium-dark-gray; silty in top 3 ft; 

clayey, well laminated in bottom 4 ft; some fossils at 

base ________________________________ 1,524-1,532 

Shale, dark-gray, laminated; a few brachiopods _ 1,532-1,534 

Coal, bright, banded, 2 in. thick at top, and slightly silty, 

medium-gray claystone; Stigmaria present _ _ _ _ _ _ 1,534-1,536

Claystone, medium-gray, crumbly, silty 1,536-1,538 

Sandstone, light-gray, fine-grained, interbedded with 50 percent medium-gray coarse siltstone _ - _ ____ 1,538-1,558 

Shale, medium-gray, relatively hard, silty _ _ ________ 1,558-1,564 

Shale, medium-gray, silty, and 50 percent siltstone, mediumgray; bottom 4 ft mostly shale; slightly fossiliferous and 

nonsilty at base _____________ - __ ____ - _ 1,564-1,588 

Shale, dark-gray to grayish-black with sideritic bands and 

lenses; very fossiliferous brachiopods, gastropods, crinoids observed. Shale, medium-dark-gray, clayey, welllaminated; sparingly fossiliferous; 2% -in. bright-banded 

coal at base (Wheatcroft coal bed) _____________ 1,588-1,618

LOWER SECTION

Supplemental log of core from the base of the coal bed at 1,618 

feet to base of the Providence Limestone Member in Peabody Coal 

Co. hole P-47. The modified description below is from a detailed 

description by William H. Smith (written commun., 1972) of the 

Illinois State Geological Survey, Urbana, 111.

Pennsylvanian System Sturgis Formation (in part) :

Claystone, medium-gray, firm; contains Stigmaria, carbonaceous in top 2 in. Underclay of the Wheatcroft 

coal bed at depth of 1,618 ft ______ - ________ 1,618-1,622

Claystone, medium-gray, silty, hard; contains pyritic 

dolomitic nodules ___________________ 1,622-1,626

Claystone, medium-gray, and light-gray sandstone, very 

fine grained, interlaminated in about equal proportions _______________________________ 1,626-1,634

Shale, medium-dark-gray, very silty at top, becomes 

clayey, laminated in bottom 2 ft; numerous carbonized plant impressions - 1,634-1,640

Coal (No. 13 coal bed), shaly; core very badly broken - 1,640-1,641

Claystone (underclay), medium-gray, fairly soft; contains Stigmaria _ _ _ _ _ _ 1,641-1,644

Claystone, similar to overlying unit, contains nodules of 

limestone similar to underlying unit 1,644-1,645
STURGIS FORMATION, WESTERN KENTUCKY COAL FIELD B23

Pennsylvania!! System Sturgis Formation (in part) Continued 

Providence Limestone Member (33 ft) :

Limestone and claystone; limestone, medium-gray, 

dense; some clay partings; f ossilif erous ; 1 ft 10 in. 

hard, calcareous, fossiliferous, greenish-gray claystone at base, containing numerous nodules and lenticular beds of limestone _ __ _ __ _.. _ 1,645-1,648

Siltstone, medium-gray; nodules of limestone ____ 1,648-1,651

Sandstone, light-gray, very fine grained; laminae and

thin beds of siltstone ___ _______________ 1,651-1,655

Shale, medium-dark-gray, silty, with about 25 percent

siltstone and sandstone ______ - ___ ---- _ 1,655-1,661

Claystone, medium-gray; numerous carbonized plant

remains and thin bands of carbonaceous shale 1,661-1,663

Sandstone, light-gray, medium-grained ; in beds as much 

as 1 ft thick ________________________ 1,663-1,671

Shale, medium-dark-gray ; siltstone laminae in top 1 ft, 

lower part clayey, laminated; contains some fossil 

shells and siderite bands ____________ - ___ - 1,671-1,674

Claystone, shale, and coal; claystone, medium-gray, calcareous, abundant fossil shells; shale, grayish-black, 

very soft, clayey, coaly, 3 in. thick at top of unit; No. 

12 coal bed is % in. thick, 5 in. above base ______ 1,674-1,675

Limestone, medium-gray, slight brownish cast, very 

dense, a single thick bed; contains fossil shells; 5%- 

in. calcareous, very fossiliferous, grayish-black claystone at base of unit. Basal part of claystone, contains coaly streaks and is in contact with top of the 

No. 11 coal bed of the Carbondale Formation ____ 1,675-1,678

REFERENCES CITED

Glenn, L. C., 1912a, The geology of Webster County: Kentucky Geol. Survey

Rept. Prog., 1910-1911, p. 25-35. 

 ' 1912b, A geological reconnaissance of the Tradewater River region,

with special reference to the coal beds: Kentucky Geol. Survey Bull. 17,

75 p.

1922, The geology and coals of Webster County: Kentucky Geol. Survey, Ser. 6, v. 5, 249 p. 

Harvey, E. J., 1956, Geology and ground-water resources of the Henderson

area, Kentucky: U.S. Geol. Survey Water-Supply Paper 1356, 227 p. 

Hopkins, M. E., 1958, Geology and petrology of the Anvil Rock Sandstone of

southern Illinois: Illinois State Geol. Survey Circ. 256, 49 p. 

Kehn, T. M., 1963, Geology of the Madisonville East quadrangle, Kentucky:

U.S. Geol. Survey Geol. Quad. Map GQ-252. 

 1964, Geology of the Madisonville West quadrangle, Kentucky: U.S.

Geol. Survey Geol. Quad. Map GQ-346.

1973, Geologic map of parts of the Dekoven and Saline Mines quadrangles, Crittenden and Union Counties, Kentucky: U.S. Geol. Survey 

Geol. Quad. Map GQ-1147. (In press.)

Lee, Wallace, 1916, Geology of the Kentucky part of the Shawneetown quadrangle: Kentucky Geol. Survey, Ser. 4, v. 4, pt. 2 ,73 p.
B24 CONTRIBUTIONS TO STRATIGRAPHY

Norwood, C. J., 1878, A report of examinations made along the paths of the 

north and south running railways in western Kentucky: Kentucky Geol. 

Survey Rept. Prog. 4, new ser., p. 285-337.

Owen, D. D., 1856, Report of the geological survey in Kentucky, made during the years 1854 and 1855: Frankfort, Ky., Kentucky Geol. Survey, 

v. 1, 416 p.

 1857, Third report of the geological survey in Kentucky, made during the years 1856 and 1857: Frankfort, Ky., Kentucky Geol. Survey, 

pt. 1, p. 1-171.

Potter, P. E., and Simon, J. A., 1961, Anvil Rock Sandstone and channel 

cutouts of Herrin (No. 6) Coal in west-central Illinois: Illinois State 

Geol. Survey Circ. 314, 12 p.

Smith, W. H., and Smith, G. E., 1967, Description of Late Pennsylvanian 

strata from deep diamond drill cores in the southern part of the Illinois 

basin: Illinois State Geol. Survey Circ. 411, 27 p., 1 pi.

*U.S. GOVERNMENT PRINTING OFFICE: 1973 543 576/11