** Four New Members of the 

Upper Cretaceous Straight Cliffs

* Formation in the Southeastern 

Kaiparowits Region

* Kane County, Utah

By FRED PETERSON

CONTRIBUTIONS TO STRATIGRAPHY

, GEOLOGICAL SURVEY BULLETIN 1274-J

Description of new stratigraphic 

units in a coal-hearing formation 

of southern Utah

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1969
UNITED STATES DEPARTMENT OF THE INTERIOR 

STEWART L. UDALL, Secretary

GEOLOGICAL SURVEY 

William T. Pecora, Director

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

Washington, D.C. 20402 - Price 30 cents (paper cover)
CONTENTS

Page

Abstract.................................... ............................................................................... Jl

Introduction................................................................................................................ 1

Fieldwork and acknowledgments.............................. ........................................ 2

Tibbet Canyon Member............................................................................................ 2

Smoky Hollow Member............................................................................................ 6

Unconformity............................................................................................................. 10

John Henry Member................................................................................................ 14

Drip Tank Member.................................................................................................. 18

Type sections of members in the Straight Cliffs Formation............................ 20

References cited........................................................................................................ 27

ILLUSTRATIONS

Page

FIGURE 1. Index map and location of type sections........................................ J3

2. Photograph showing type locality of Tibbet Canyon Member.... 4

3. Columnar section of members in Straight Cliffs Formation...... 5

4. Photograph showing type locality of Smoky Hollow Member.... 7

5. ^Diagram showing; relations of members and units in Straight

Cliffs Formation .............................................................................. 8

6-9. Photographs:

6. Unconformity between Smoky Hollow Member and

John Henry Member.......................................................... 11

7. Fluvial channel sandstone at base of John Henry 

Member resting on erosion surface cut into top 

of Smoky Hollow Member............ ..........-.. ............ 12

8. Type locality of John Henry Member....... ................... 15

9. Type locality of Drip Tank Member................................ 19

III

CONTRIBUTIONS TO STRATIGRAPHY

FOUR NEW MEMBERS OF THE UPPER CRETACEOUS

STRAIGHT CLIFFS FORMATION IN THE SOUTHEASTERN

KAIPAROWITS REGION, KANE COUNTY, UTAH

By FRED PETERSON

ABSTRACT

The Straight Cliffs Formation is divided here into four new members in 

the southeastern Kaiparowits region of south-central Utah. In ascending 

order, the members and their thicknesses at the type localities are the Tibbet 

Canyon Member, 104 feet; the Smoky Hollow Member, 116 feet; the John 

Henry Member, 741 feet; and the Drip Tank Member, 141 feet. The Tibbet 

Canyon and Drip Tank Members are generally cliff forming sandstone units, 

whereas the Smoky Hollow and John Henry Members are ledge- and slopeforming units composed of interbedded sandstone, mudstone, and coal. The 

John Henry Member contains the major coal resources of the Kaiparowits 

region.

The Straight Cliffs Formation was deposited in marine and nonmarine < 

environments on the southwest side of the Late Cretaceous Western Interior 

seaway. The Tibbet Canyon Member was deposited mainly in beach and 

shallow-water marine environments, and the Smoky Hollow Member was 

deposited in fluvial, flood-plain, lagoonal, and paludal environments. A period 

of regional erosion occurred at the end of deposition of the Smoky Hollow 

Member, and an unconformity separates the Smoky Hollow Member from the 

overlying John Henry Member. The John Henry Member was deposited in 

marine and nonmarine environments similar to those of the two underlying 

members, and the Drip Tank Member was deposited in fluvial environments.

Fossil evidence indicates that the Tibbet Canyon and Smoky Hollow 

Members are middle to about early late Turonian in age and correlate approximately with the middle of the Carlile Shale in the standard reference sequence 

for the Western Interior. The John Henry and Drip Tank Members are about 

middle Coniacian to early Campanian in age and correlate approximately 

with the middle and upper parts of the Niobrara Formation.

INTRODUCTION

The Straight Cliffs Sandstone was named by Gregory and 

Moore (1931, p. 91) for exposures along the Straight Cliffs escarpment several miles south of Escalante, Utah, in the northern part

Jl
J2 CONTRIBUTIONS TO STRATIGRAPHY

of the Kaiparowits Plateau (fig. 1). In most parts of the plateau 

the formation contains significant amounts of rocks other than 

sandstone, and for this reason Peterson and Waldrop (1965, 

p. 62-63) applied the more general name Straight Cliffs Formation to the formation.

Recent mapping in the southeastern Kaiparowits region indicates that the Straight Cliffs Formation can be divided into four 

members, and observations by the writer indicate that these 

members can be recognized elsewhere in the Kaiparowits Plateau. 

In ascending order, the members herein named are the Tibbet 

Canyon Member, the Smoky Hollow Member, the John Henry 

Member, and the Drip Tank Member. The Smoky Hollow and John 

Henry Members are subdivided into several informal units on 

the basis of characteristic associations of sedimentary structures, 

lithologies, or fossils.

Although the main purpose of this report is to describe the 

new members, the report also describes for the first time an intraformational unconformity that separates the Smoky Hollow Member from the John Henry Member. The best evidence of the unconformity is found in the southeastern Kaiparowits region, but the 

unconformity may extend throughout the Kaiparowits Plateau.

FIELDWORK AND ACKNOWLEDGMENTS

This report is a byproduct of a comprehensive stratigraphic 

study and geologic-mapping program in the Kaiparowits region 

that has been in progress since 1963. The purpose of the work 

is to evaluate the occurrence and distribution of coal beds in order 

to classify Federal lands for their coal resources. Mapping was 

done at the scale of 1:24,000, and sections of parts of the Straight 

Cliffs Formation were measured about 1-2 miles apart along outcrops of the formation. Lateral relations were determined by 

tracing key sandstone beds and member contacts in the field. 

Other geologists in the mapping program are W. E. Bowers, E. V. 

Stephens, H. A. Waldrop, and H. D. Zeller, all of the U.S. Geological 

Survey. W. A. Cobban, also of the Survey, identified the fossils. 

Capable assistance in the field was given by C. J. Flynn, G. W. 

Horton, B. E. Law, 0. L. Ligon, and R. L. Sutton.

TIBBET CANYON MEMBER

The Tibbet Canyon Member is named for a cliff-forming sandstone unit at the base of the Straight Cliffs Formation that lies 

above the generally slope forming Tropic Shale. The member was 

informally named the lower sandstone member of the Straight 

Cliffs Formation by Peterson and Waldrop (1965, p. 63). The 

Tibbet Canyon is well exposed in the southwestern and central
NEW MEMBERS, STRAIGHT CLIFFS FORMATION, UTAH J3

38°

112° 111"

UTAH

Type sections ^

(1)Tibbet Canyon Member

(2) Smoky Hollow Member 

(5) John Henry Member 

(4) Drip Tank Member

37°

0 

I i i

25 MILES

Tropic o

GARFIELD CPU 

KANE COUNTY

Southeastern

Kaiparowits

region

Glen Canyon City

COCONINO COUNTY

FIGURE 1. Southern part of Kaiparowits Plateau and location of 

type sections of members in Straight Cliffs Formation.
J4 CONTRIBUTIONS TO STRATIGRAPHY

parts of the region, but farther northeast, and especially at the 

Straight Cliffs escarpment, the member is largely concealed by 

talus. The type locality of the Tibbet Canyon Member is near the 

mouth of Tibbet Canyon (fig. 1) and is shown in figure 2. The 

type section is illustrated in figure 3, and the measured section 

is given at the end of the report.

The Tibbet Canyon Member is about 70-185 feet thick in the 

southeastern Kaiparowits region. In the northwestern Kaiparowits 

region, near Tropic, Utah, the lowest unit in a section measured 

by J. C. Lawrence (in Robison, 1966, p. 23) and tentatively assigned by the writer to the Tibbet Canyon Member is 84 feet thick.

FIGURE 2. Type locality of Tibbet Canyon Member. View is toward the 

west on the north side of Tibbet Canyon. 1, Type measured section; member 

is 104 feet thick. Kt, Tropic Shale; Kst, Tibbet Canyon Member; Kss, Smoky 

Hollow Member.

The Tibbet Canyon is composed mainly of yellowish-gray to 

grayish-orange very fine grained to medium-grained horizontally 

stratified and cross-stratified sandstone. The lower part of the 

member is interbedded with dusky-yellow to light-olive-gray mudstone beds that are southwestward- or southward-thinning 

tongues of the Tropic Shale. The lower contact is generally placed 

at the base of the lowest persistent sandstone bed, but at several
NEW MEMBERS, STRAIGHT CLIFFS FORMATION, UTAH J5

SERIES

D

0

LLJ

<

H

LJ

o: 

o

o:

LU 

0.

0.

D

STAGE

c 

ro

(0

a 

E

CO

O

c

'E

c

(0 (/)

 7 

C

'u

'E

0

o

c 

ro

c 

o

D tFORMATION

Wahweap 

Formation

c 

.2 2

11

£l w ^ t ° o 

0 £

.5? o 

ro .Q 

£ ro 

c/> "

Tropic 

Shale

MEMBER

Drip Tank

Member

Smoky Hollow

Member

Tibbet Canyon

Member

THICKNESS 

(FEET)

1250-*-

141

741

116

104 

641±

LITHOLOGY

-T~_ _r*_ _

_~_~_~_~

^T-Z-^

°°°. -.-. :.'.

' 000-' ' ' '.

- '_ ^

ll' ' 

-i_ _ ^r_

 __-^ L_ - -

^-3^

" J_ _rrl. £-

 :_ =_-^_-=.

.....

-r-^-_-_-_

l___-_'-J__ i

;

;

1

:

1

^.- .-]

- - - --

^j=^=:

 _

>!>i-i-i

THICKNESS 

(FEET)

366.0

C6.0

104.0

143.5

37.0

84.5

\20.0

84.5

xfis

INFORMAL 

UNITS

Upper barren

Rees coal zone

M ddle barren 

zone

Christensen coal 

zone

Lower barren zone

Lower coal zone

-UNCONFORMITYCalico bed

FEET

- 0

- 100 

- 200

FIGURE 3. Composite columnar section of members in Straight Cliffs Formation at type localities in southern part of Kaiparowits Plateau, Utah.

326-942 O - 69 - 2
J6 CONTRIBUTIONS TO STRATIGRAPHY

localities the vertical sequence of beds is entirely gradational, and 

the lower contact is placed arbitrarily where sandstone is the 

dominant lithology. The upper contact is generally sharp and 

is placed where the cliff-forming sandstone of the Tibbet Canyon 

Member is in contact with the lowest overlying mudstone, carbonaceous mudstone, or coal bed of the Smoky Hollow Member.

Evidence that the Tibbet Canyon was deposited in beach and 

shallow-marine environments includes fossils inoceramids, cephalopods, shark teeth, and Ophiomorpha sp. and its stratigraphic 

position between underlying offshore marine beds in the Tropic 

Shale and overlying lagoonal and paludal beds in the Smoky 

Hollow Member. A vertical sequence of bedding structures that 

is typical of beach and nearshore marine deposition of sandstone 

beds in the John Henry Member is rarely present and, consequently, is of little value for interpreting environments of deposition in the Tibbet Canyon Member. The Tibbet Canyon was deposited during a northward or northeastward regression of the 

shoreline of the Late Cretaceous Western Interior seaway.

The pelecypod Inoceramus howelli White was found in the 

Tibbet Canyon Member and, according to W. A. Cobban (oral 

commun., 1966), indicates a middle Turonian age and suggests 

an approximate correlation of the Tibbet Canyon with the Blue 

Hill Shale Member of the Carlile Shale in the standard reference 

sequence for the Western Interior (Cobban and Reeside, 1952).

SMOKY HOLLOW MEMBER

The Smoky Hollow Member is a cliff- and slope-forming unit 

of interbedded sandstone, mudstone, carbonaceous mudstone, and 

coal that lies above the cliff-forming Tibbet Canyon Member. 

Strata of the Smoky Hollow Member were included in the lower 

part of the middle member of the Straight Cliffs Formation by 

Peterson and Waldrop (1965, p. 63-64). Subsequent investigation 

has shown that an unconformity divides the middle member of 

Peterson and Waldrop into two units that are herein named the 

Smoky Hollow and John Henry Members of the Straight Cliffs 

Formation. The Smoky Hollow is moderately well exposed in the 

southwestern and central parts of the region, but farther northeast, and especially along the Straight Cliffs escarpment, the member is generally concealed by talus. The type locality of the Smoky 

Hollow Member is on the west side of Smoky Hollow (fig. 1) and 

is shown in figure 4. The type section is illustrated in figure 3, 

and the measured section is given at the end of the report.

The Smoky Hollow Member is about 24-132 feet thick in the 

southeastern Kaiparowits region. In the northwestern Kaiparowits
NEW MEMBERS, STRAIGHT CLIFFS FORMATION, UTAH J7

FIGURE ^. Type locality of Smoky Hollow Member. View is toward the west 

across Smoky Hollow. 2, Type measured section; member is 116 feet thick. 

Kt, Tropic Shale; Kst, Tibbet Canyon Member; Kss, Smoky Hollow Member; 

Ksj, John Henry Member.

region, the group of beds that includes units 2-9 above the base 

of a section measured by J. C. Lawrence (in Robison, 1966, p. 23) 

and tentatively assigned by the writer to the Smoky Hollow Member is 231 feet thick. About 9 miles northwest of Escalante, Utah, 

the Smoky Hollow is about 331 feet thick (E. V. Stephens, oral 

commun., 1967).

The Smoky Hollow consists of three informal units: a coal 

zone at the base, a barren zone in the middle, and the Calico bed 

at the top (fig. 5). The coal zone ranges in thickness from 0 to 

about 47 feet and contains pale-brown to black carbonaceous 

mudstone and coal beds that range in thickness from 0 to about 

4 feet but generally are less than 2 feet thick. The barren zone, 

so named because it lacks coal, is about 13-110 feet thick. It contains dusky-yellow to light-olive-gray bentonitic mudstone interbedded with pale-yellowish-brown and grayish-orange very fine 

grained to medium-grained horizontally stratified and crossstratified sandstone. Scattered quartz and chert granules and chert 

pebbles occur locally in the sandstone beds. The Calico bed ranges
J8 CONTRIBUTIONS TO STRATIGRAPHY

c 

.2 "S 

£

!H 

O

fa 

Jg

O

-i-> 

x

'5

0) . X i-3

-)J

 s

 a 

rt

tf
NEW MEMBERS, STRAIGHT CLIFFS FORMATION, UTAH J9

in thickness from 0 to about 51 feet and consists of white to very 

light gray fine- to coarse-grained poorly sorted cross-stratified 

sandstone. Locally, scattered quartz and chert granules, chert pebbles, or conglomerate lenses are common. The Calico bed interfingers with the upper part of the barren zone and is unconformably overlain by the John Henry Member.

The Smoky Hollow Member was deposited in a variety of nonmarine environments. The presence of coal and carbonaceous 

mudstone suggests deposition of the coal zone in paludal and 

lagoonal environments. The barren zone contains sandstone and 

mudstone strata that were deposited in fluvial and flood-plain environments. Fluvial sandstones in the barren zone contain abundant low- and high-angle medium-scale trough cross-stratification, 

crossbedding that dips down the axis of channels, and cut-and-fill 

structures. Ripple cross-laminae are common in the upper 1-3 feet 

of many of these beds. Very thin bedded to thin-bedded mudstone 

and interbedded laminated, ripple cross-laminated, or ripple driftlaminated sandstone are interpreted as flood-plain deposits because 

they are found between the fluvial sandstones. The dusky-yellow 

to light-olive-gray bentonitic mudstone beds are especially common 

in strata interpreted as flood-plain deposits in the southeastern 

Kaiparowits region. The Calico bed contains channels and other 

bedding structures similar to those in the fluvial sandstones of 

the barren zone, although the Calico bed generally lacks ripple 

cross-lamination and is composed of more poorly sorted sandstone. 

These criteria suggest that the Calico bed was deposited mainly 

in fluvial environments. The above data and the interfingering of 

the Smoky Hollow Member with the Tibbet Canyon Member (fig. 5) 

indicate that the Smoky Hollow Member was deposited in fluvial, 

flood-plain, lagoonal, and paludal environments on the landward or 

generally southwest side of beach or shallow-marine sands of the 

Tibbet Canyon Member.

Fossils diagnostic of age have not been found in the Smoky 

Hollow, but the lower part of the member grades northeastward 

into the upper part of the Tibbet Canyon Member (fig. 5), which 

contains Inoceramus howelli White. This indicates that the lower 

part of the Smoky Hollow is middle Turonian in age. Because the 

Smoky Hollow Member consists of a continuous sequence of beds, 

lacks unconformities, and interfingers with the Tibbet Canyon 

Member, the upper part of the Smoky Hollow Member is probably 

only slightly younger than the lower part. Thus, the Smoky Hollow 

Member is middle Turonian to perhaps early late Turonian in age. 

In terms of the standard reference sequence for the Western Interior region (Cobban and Reeside, 1952), the Smoky Hollow Member
J10 CONTRIBUTIONS TO STRATIGRAPHY

correlates approximately with the upper part of the Blue Hill 

Shale Member and possibly with the lower part of the Turner 

Sandy Member of the Carlile Shale.

UNCONFORMITY

Detailed mapping disclosed that an unconformity separates the 

Smoky Hollow Member from the overlying John Henry Member 

and that this unconformity is the only clearly defined stratigraphic 

horizon in the Straight Cliffs Formation that can be traced 

throughout the region. The lateral persistence of the unconformity 

in a sequence of lenticular and interfingering marine and nonmarine beds suggests that the unconformity has greater stratigraphic significance than any of the numerous local unconformities in the Straight Cliffs Formation. Evidence of the unconformity 

is divided into three categories: local evidence that can be recognized at the outcrop; regional evidence from thickness variations 

and truncation of strata across a wide area; and paleontological 

evidence that indicates the period of time represented by the 

unconformity.

Local evidence of the unconformity is as follows:

1. Bedding planes at the top of the Smoky Hollow Member that 

dip at low angles are truncated by strata at the base of the 

John Henry Member (fig. 6).

2. Fluvial channel sandstones at the base of the John Henry rest 

on an erosion surface that is cut down as much as 10 feet 

into the top of the Smoky Hollow (fig. 7) ; however, local 

relief on the unconformity is generally less than 5 feet where 

channel sandstones are not present.

3. A basal brown conglomeratic sandstone bed of the John Henry 

Member contains lithologic and bedding features which suggest that it formed as a residual deposit on the Calico bed 

after regional erosion had ended (fig. 6). This sandstone bed 

is medium gray to pale yellowish brown and weathers pale 

brown. It is about 0-15 feet thick and consists of fine- to 

coarse-grained well-cemented sandstone that contains carbonaceous grains and flecks, thin lenses of carbonaceous mudstone, and scattered quartz and chert granules and chert 

pebbles which occur locally as small conglomerate lenses. 

Bedding is generally indistinct, but locally it is irregularly 

horizontal and very thin bedded to thin bedded; cross-stratification is rare. Vertical external molds of plants that were 

probably root systems also occur locally. The general lack 

of current bedding structures and the similar size and composition of the grains, granules, and pebbles in this bed and
NEW MEMBERS, STRAIGHT CLIFFS FORMATION, UTAH Jll

FIGURE 6. Unconformity (arrows) between Calico bed at top of Smoky 

Hollow Member and overlying basal brown conglomeratic sandstone bed of 

John Henry Member in Tibbet Canyon (NE%SWiiSE% sec. 10, T. 42 S., 

R. 3 E.). Note low-angle truncation of bedding planes in Calico bed.

in the Calico bed suggest that much of the material in the 

basal brown conglomeratic bed was weathered from the 

Calico bed. The basal brown conglomeratic sandstone bed 

interfingers with other strata in the John Henry Member, 

and the bed is only present at the base of the nonmarine 

part of the John Henry Member, which is in the southwestern and central parts of the region.

4. Conglomerate lenses of chert and quartzite pebbles and cobbles 

occur locally as a basal conglomerate at the bottom of the 

marine part of the John Henry Member in the northeastern 

part of the region.

Regional evidence of the unconformity is found in low-angle 

truncation of the Smoky Hollow Member in the southwestern and 

northeastern parts of the region. Near Wahweap Creek about 3 

njiles east-southeast of Glen Canyon City, the Calico bed at the 

top of the Smoky Hollow Member was removed by erosion before 

deposition of the John Henry Member, and the John Henry rests 

directly on the barren zone of the Smoky Hollow Member (fig. 5). 

In this area the Smoky Hollow is only 24 feet thick. In the central
J12 CONTRIBUTIONS TO STRATIGRAPHY

FIGURE 7. Fluvial channel sandstone at base of John Henry Member (Ksj) 

resting on erosion surface cut into Calico bed at top of Smoky Hollow 

> Member (Kss) in Smoky Hollow (NE^SE^SE^ sec. 32, T. 41 S., R. 4 E.). 

A sharp contrast between the white Calico bed and the darker sandstones 

of the John Henry Member is evident. Calico bed is about 18 feet thick on 

either side of channel.

part of the region the Calico bed is present and the Smoky Hollow 

Member is 121 feet thick. The upper approximately 60 feet of 

the Tibbet Canyon Member in the central area grades southwestward into the lower part of the Smoky Hollow Member, resulting 

in a total of 181 feet of strata in the central area that is equivalent 

to or younger than the 24 feet of Smoky Hollow in the Wahweap 

Creek area. From these figures it is apparent that an approximate 

minimum of 157 feet of Smoky Hollow Member was removed from 

the southwestern part of the region prior to deposition of the 

overlying John Henry Member.

The Calico bed was also eroded from the northeastern part 

of the region prior to deposition of the John Henry Member 

(fig. 5). Although detailed stratigrapic relations cannot be determined accurately because of talus cover, no interfingering of the 

Smoky Hollow and Tibbet Canyon Members is known to occur in 

this area, and the contact between these members is apparently 

a time-equivalent or nearly time equivalent surface. The Smoky 

Hollow is 31 feet thick at the east end of the Straight Cliffs escarp-
NEW MEMBERS, STRAIGHT CLIFFS FORMATION, UTAH J13

ment and 121 feet thick in the central area, so that an approximate 

minimum of 90 feet of strata is inferred to have been eroded from 

the Smoky Hollow Member in the area at the east end of the 

Straight Cliffs escarpment before deposition of the John Henry 

Member.

The above-mentioned figures of at least 157 feet of erosion in 

the southwestern part of the region and 90 feet of erosion in the 

northeastern part of the region indicate the minimum amount of 

strata that was removed prior to deposition of the John Henry 

Member. Considerably more strata were probably deposited and 

subsequently eroded from the top of the Smoky Hollow Member 

because local evidence of the unconformity is found in the central 

area and because the Calico bed and the Smoky Hollow Member 

are thicker in the northwestern part of the Kaiparowits Plateau.

Robison (1966, p. 20) found that a conglomeratic sandstone 

bed in the Tropic, Utah, area ranges in thickness from 60 to 360 

feet. This sandstone bed is probably the Calico bed, and the greater 

thickness of the Calico bed in the Tropic area suggests either 

northwestward depositional thickening or that the Smoky Hollow 

Member may have been considerably thicker in the southeastern 

Kaiparowits region before erosion and subsequent deposition of 

the John Henry Member. The presence of the unconformity in the 

Tropic area may account for the anomalous range in thickness of 

Robison's (1966, p. 20) lower member of the Straight Cliffs Formation, which probably includes the Tibbet Canyon, Smoky Hollow, and John Henry (lower part) Members. In a section 9 miles 

northwest of Escalante, Utah, measured by E. V. Stephens (oral 

commun., 1967), the Calico bed is 104 feet thick and the Smoky 

Hollow Member is 331 feet thick. These measurements also suggest 

that northwestward depositional thickening occurred or that the 

Smoky Hollow may have been thicker in the southeastern Kaiparowits region.

Fossil evidence also suggests the presence of an unconformity 

between the John Henry and Smoky Hollow Members. In strata 

below the unconformity, the part of the Smoky Hollow above the 

youngest part of the Tibbet Canyon (fig. 5) does not contain 

fossils diagnostic of age, but the Tibbet Canyon Member contains 

the middle Turonian fossil Inoceramus howelli White, The presence of this fossil and the apparently continuous deposition of the 

Tibbet Canyon and succeeding beds of the Smoky Hollow Member 

suggest that the upper part of the Smoky Hollow is of middle 

Turonian or early late Turonian age. In strata above the unconformity, the lower marine mudstone tongue of the John Henry
J14 CONTRIBUTIONS TO STRATIGRAPHY

Member contains Inoceramus stantoni Sokolow and Protexanites 

shoshonensis (Meek) in a bed about 50-70 feet above the base, 

and these fossils indicate an age no older than about middle Coniacian, according to W. A. Cobban (oral commun., 1966) and Scott 

and Cobban (1964, p. L15).

The paleontological evidence suggests that the approximate 

minimum time-stratigraphic interval represented by the unconformity includes the uppermost part of the Turonian Stage and 

the lower part of the Coniacian Stage. In terms of the standard 

reference sequence for the Western Interior region, strata correlative with the upper part of the Carlile Shale and the lower and 

lower middle parts of the Niobrara Formation were eroded or 

never deposited in the southeastern Kaiparowits region.

The unconformity at the Carlile-Niobrara boundary has been 

reported in other parts of the Colorado Plateau: by Dane (1960) 

in the San Juan Basin of New Mexico, and by Hunt, Averitt, and 

Miller (1953, p. 83) in the Henry basin of south-central Utah. 

Reconnaissance studies by the writer suggest that the unconformity is probably present in Black Mesa basin of northeastern 

Arizona at the base of the marine shale tongue of the Toreva 

Formation.

JOHN HENRY MEMBER

The John Henry Member is named for a cliff- and slope-forming unit of interbedded sandstone, mudstone, carbonaceous mudstone, and coal that lies below the cliff-forming Drip Tank Member. 

The John Henry was included in the upper part of the middle 

member of the Straight Cliffs Formation by Peterson and Waldrop 

(1965, p. 63-64). The member is moderately well exposed in the 

southwestern part of the region. In the central part of the region 

where many of the coal beds have been burned, the member is 

generally concealed by talus accumulations of baked mudstone 

and sandstone, and exposures are best near the bottoms of dry 

washes. In the northeastern part of the region, slope-forming units 

of coal and mudstone are generally concealed by talus and soil. 

The type locality of the John Henry Member is in Smoky Hollow, 

about 3 miles east of John Henry Canyon (fig. 1) ; it is shown 

in figure 8. The type section is illustrated in figure 3, and the 

measured section is given at the end of the report.

The John Henry Member is about 660 feet thick in the southwestern part of the region and thickens irregularly northeastward 

to about 1,080 feet near the Straight Cliffs escarpment. In the 

northwestern Kaiparowits region, the group of beds that includes
NEW MEMBERS, STRAIGHT CLIFFS FORMATION, UTAH J15

units 10-31 above the base of a section measured by J. C. Lawrence 

(in Robison, 1966, p. 21-23) and tentatively assigned by the writer 

to the John Henry Member is 657 feet thick.

V*

FIGURE 8. Type locality of John Henry Member. View is toward the west 

across Smoky Hollow up small tributary canyon. 3, Type measured section; 

member is 741 feet thick. 33, 39, 52 indicate prominent sandstone units in 

measured section at end of report. Kss, Smoky Hollow Member; Ksj, John 

Henry Member; Ksd, Drip Tank Member.

The John Henry Member consists of a predominantly nonmarine facies in the southwestern and central parts of the region 

and a predominantly marine facies in the northeastern part. The 

predominantly nonmarine facies consists of six informal units 

that are distinguished primarily by the presence or absence of coal. 

In ascending order, these are lower coal zone, lower barren zone, 

Christensen coal zone, middle barren zone, Rees coal zone, and 

upper barren zone. Typical lithologies in the nonmarine facies 

include pale-yellowish-brown to grayish-orange very fine grained 

to medium-grained horizontally stratified and cross-stratified sand-
J16 CONTRIBUTIONS TO STRATIGRAPHY

stone, dusky-yellow to light-olive-gray bentonitic mudstone, darkgray to black carbonaceous mudstone, and coal.

The predominantly marine facies in the northeastern part of 

the region at the Straight Cliffs escarpment consists of five cliffforming marine sandstone beds, two marine mudstone tongues, 

and two nonmarine coal zones. In ascending order, these are lower 

marine mudstone tongue, A sandstone bed, B sandstone bed, 

Christensen coal zone, C sandstone bed, D sandstone bed, upper 

marine mudstone tongue, G sandstone bed, and Alvey coal zone. 

The upper marine mudstone tongue grades southwestward into 

the E and F sandstone beds. Typical lithologies in the marine 

facies include very light gray to moderate-yellowish-brown very 

fine grained to fine-grained horizontally stratified and cross-stratified sandstone and light-olive-gray mudstone. Conglomerate lenses 

of quartz granules, chert pebbles, and quartzite pebbles and cobbles are locally present in the lower marine mudstone tongue and 

in the A sandstone bed. The generalized relations of the various 

units in both the marine and the nonmarine facies of the John 

Henry Member are shown diagrammatically in figure 5.

The John Henry Member contains coal deposits of considerable 

economic potential, and several companies are drilling to evaluate 

the subsurface extent and continuity of the coal beds. The lower 

coal zone generally contains coal beds that are less than 3 feet 

thick. Locally, however, one or two of the coal beds are thicker 

than 4 feet, and the thickest bed found measured 12.6 feet. The 

Christensen coal zone contains the thickest and most extensive 

coal beds in the region. This zone generally includes one to four 

coal beds that are 4 feet or more thick, and the thickest bed found 

measured 29.6 feet. The Henderson coal zone of Robison (1966, 

p. 37) in the Tropic, Utah, area is probably correlative with the 

Christensen coal zone. The Rees coal zone contains one or two 

coal beds that are less than 3 feet thick in the southwestern part 

of the region, but in the central part of the region this zone contains as many as three coal beds that are 4 feet or more thick, and 

the thickest bed found measured 9.5 feet. Most of the Alvey coal 

zone has been eroded from the southeastern Kaiparowits region, 

but one bed is 11.8 feet thick. Doelling (1967, p. 8, coal zones 

A and B) found several coal beds that were more than 4 feet 

thick in the Alvey coal zone near Escalante, Utah. The Christensen 

and Alvey coal zones are named at the suggestion of H. D. Zeller 

of the U.S. Geological Survey after coal mines in the northern 

part of the Kaiparowits region. The Rees coal zone is named for 

Rees Canyon, a small tributary canyon to Last Chance Creek 

canyon in the central part of the southeastern Kaiparowits region.
NEW MEMBERS, STRAIGHT CLIFFS FORMATION, UTAH J17

The John Henry Member was deposited in a variety of marine 

and nonmarine environments. The nonmarine facies of the member 

contains lithologies and bedding structures that are similar to 

those in the Smoky Hollow Member and that indicate deposition 

in fluvial, flood-plain, paludal, and lagoonal environments. Sandstone and mudstone beds in the marine facies of the member 

contain marine fossils that include inoceramids, cephalopods, 

shark teeth, and Ophiomorpha sp. The A through G marine sandstone beds locally contain a vertical sequence of bedding structures that aids in distinguishing these beds from nonmarine 

sandstones. The lower part of the sequence contains horizontal 

stratification and low-angle medium- to large-scale trough crossstratification, the middle part contains low- and high-angle 

medium-scale trough cross-stratification, and the upper part 

contains very low angle (less than about 5°) medium- to largescale wedge-planar cross-stratification. Bedding structures and 

sequences similar to these have been found in sands deposited 

in modern beach and shallow-water environments (Hoyt and 

Weimer, 1963; McKee, 1957; Thompson, 1937), and similar criteria have been used for interpreting beach and shallow-water 

environments of deposition for certain Cretaceous marine sandstones in Wyoming (Jacka, 1965) and Colorado (Masters, 1967). 

The criteria listed above and the interfingering relations shown 

in figure 5 indicate that the nonmarine facies was deposited in 

fluvial, flood-plain, lagoonal, and paludal environments and that 

the marine facies was deposited in beach, shallow-water, and offshore marine environments.

Fossils that are diagnostic of age are scarce in the John Henry 

Member, but several collections allow reasonably good correlation 

and age assignments. Inoceramus stantoni Sokolow and Protexanites shoshonensis (Meek) were found in the lower marine mudstone tongue; Inoceramus (Volviceramus) involutus Sowerby was 

found in the A sandstone bed; Inoceramus sp. which has a truncate 

anterior margin came from about the top of the upper marine 

mudstone tongue; and Inoceramus cf. /. (Cordiceramus) mulleri 

Petrascheck was found in the G sandstone bed. According to W. A. 

Cobban (written commun., 1966) and Scott and Cobban (1964, 

p. L15, and table 2), these fossils indicate that the lower part of 

the John Henry Member is middle and (or) late Coniacian in age, 

the middle part is Santonian in age, and the upper part is approximately early Campanian in age. The John Henry Member correlates approximately with the middle and upper parts of the Niobrara Formation at Pueblo, Colo. (Scott and Cobban, 1964), and 

the lower and upper marine mudstone tongues correlate approxi-
J18 CONTRIBUTIONS TO STRATIGRAPHY

mately with the Mulatto and Satan Tongues, respectively, of the 

Mancos Shale in the San Juan Basin, N. Mex. (Cobban and 

Reeside, 1952, chart lOb, col. 15).

DRIP TANK MEMBER

The Drip Tank Member is a cliff-forming sandstone unit that 

is resistant to erosion and generally supports an irregular bench 

or stripped structural surface at the top of the Straight Cliffs 

Formation. The lower part of the member generally forms cliffs, 

but talus accumulations conceal the lower contact in many places. 

The upper part of the member and the lower part of the overlying 

Wahweap Formation are generally stripped back and form a broad 

bench. Windblown sand on this bench and talus accumulations at 

the foot of bluffs composed of the Wahweap Formation conceal 

the uppermost part of the Drip Tank Member in many places. 

The member was informally named the upper sandstone member 

of the Straight Cliffs Formation by Peterson and Waldrop (1965, 

p. 64). The type locality of the Drip Tank Member is near the 

mouth of Drip Tank Canyon (fig. 1) and is shown in figure 9. 

The type section is illustrated in figure 3, and the measured section 

is given at the end of the report.

The Drip Tank Member is about 141-255 feet thick in the 

southeastern Kaiparowits region. In the northwestern Kaiparowits 

region, the highest unit in a section measured by J. C. Lawrence 

(in Robison, 1966, p. 21) and tentatively assigned by the writer 

to the Drip Tank Member is 523 feet thick.

The Drip Tank Member consists mainly of pale-yellowishbrown to grayish-orange fine- to medium-grained cross-stratified 

sandstone. The well-cemented lower 30-80 feet contains scattered 

quartz and chert granules and chert pebbles or scattered conglomerate lenses. Sandstone and mudstone pebbles and cobbles, 

petrified logs, and bone fragments are also found in the lower 

part, and scattered lenses of mudchip conglomerate occur near the 

top of the member. Dusky-yellow to light-olive-gray bentonitic 

mudstone lenses as much as 20 feet thick are scarce but may 

occur in any part of the member.

The lower part of the Drip Tank Member probably interfingers 

with the upper part of the John Henry Member, but this cannot 

be demonstrated conclusively because talus conceals the contact 

in many places. Where exposures are good, the lower contact is 

placed at the top of the highest mudstone bed underlying the thick 

cliff-forming sandstone of the Drip Tank Member. The upper part 

of the Drip Tank Member interfingers with the lower part of the 

Wahweap Formation, and where exposures are good the upper
NEW MEMBERS, STRAIGHT CLIFFS FORMATION, UTAH J19

FIGURE 9. Type locality of Drip Tank Member. View is toward the north 

across Drip Tank Canyon. 4, Type measured section; member is 141 feet 

thick, a, Dirt road that leads to Glen Canyon City, Utah (about 32 miles). 

Ksj, John Henry Member; Ksd, Drip Tank Member; Kw, Wahweap Formation.

contact is placed at the base of the lowest mudstone bed overlying the Drip Tank Member. Where exposures are poor, the 

contacts can be placed at the top or the bottom (whichever is 

appropriate) of prominent and laterally continuous sandstone 

beds that occur at or near the sandstone-mudstone contact and 

that can be traced laterally as key beds.

The Drip Tank Member contains abundant low- and high-angle 

medium-scale trough cross-stratification, fluvial channels in which 

the crossbedding dips down the axis of the channels, and cut-andfill structures; but the member lacks marine fossils or bedding 

structures typical of marine beds. These features suggest that the 

member was deposited in fluvial environments. Fossils diagnostic 

of an age more restricted than Late Cretaceous have not been 

found in either the Drip Tank Member or the overlying Wahweap 

Formation. The Drip Tank Member is probably only slightly 

younger than the upper beds of the John Henry Member because
J20 CONTRIBUTIONS TO STRATIGRAPHY

these members apparently interfinger; therefore, the Drip Tank 

Member is probably about early Campanian in age. This approximate age suggests that the member was deposited at about the 

same time as the Emery Sandstone Member of the Mancos Shale 

in central Utah and the Point Lookout Sandstone in the San Juan 

Basin of northwestern New Mexico.

TYPE SECTIONS OF MEMBERS 

IN THE STRAIGHT CLIFFS FORMATION

Colors in the following descriptions follow the nomenclature 

of 'the "Rock-Color Chart" (Goddard and others, 1963), and 

bedding classification generally follows that of McKee and Weir 

(1953). Partings in coal beds are not thicker than the adjacent 

coal seams, and a parting 1 foot or more thick is considered to 

divide the coal into two separate beds. Very thin coal beds are 

those less than 1 foot thick, and they are not 'listed.

Type section of Drip Tank Member

[Section 4 (fig. 1) measured up east side of small tributary canyon on north side of Drip Tank 

Canyon in the NEVtNE'/i sec. 24, T. 40 S., R. 3 E., Kane County, Utah]

Wahweap Formation (part) :

81. Sandstone, grayish-orange (weathers very pale orange), finegrained, crossbedded; forms prominent cliff.............................. 32.0

80. Mudstone, dusky-yellow, very thin bedded to thin-bedded;

forms slope-.........---.-..........-..---.--.--.---.-......-.........-----.-.---................- 29.0

79. Sandstone, pale-yellowish-brown (weathers grayish brown),

fine-grained, ripple cross-laminated; forms small ledge.......... 1.0

78. Mudstone; same as unit 80.............................................................. 3.0

Total measured Wahweap Formation........................................ 65.0

Straight Cliffs Formation: 

Drip Tank Member:

77. Sandstone, pale-yellowish-brown (weathers grayish 

brown), fine-grained, crossbedded; upper 2 ft is ripple 

cross-laminated; forms small cliff........................................ 7.0

76. Sandstone, medium-light-gray, fine-grained, very thin 

bedded to thin-bedded and crossbedded; upper 1 ft is 

mudstone (same as unit 80) that grades down into siltstone and mudstone; forms cliff..........---...........-.............. .. 18.0

75. Sandstone, grayish-orange (weathers very pale orange) , 

medium-grained, very thin bedded to thin-bedded and 

crossbedded; forms slope...................................................... 32.0

74. Sandstone, pale-yellowish-brown to grayish-orange, fineto coarse-grained, crossbedded; locally contains granule 

and pebble conglomerate lenses; forms prominent cliff.... 84.0

Total Drip Tank Member.................................................. 141.0
NEW MEMBERS, STRAIGHT CLIFFS FORMATION, UTAH J21

Type section of Drip Tank Member Continued 

Straight Cliffs Formation Continued

John Henry Member (part) : r/fte?fs 

73. Mudstone, medium-light-gray; forms slope............................ 4.5

72. Sandstone, light-gray (weathers grayish orange), mediumto coarse-grained, crossbedded; forms cliff........................ 25.0

71. Mudstone; same as unit 73; forms slope, base concealed.... 3.0

Total measured John Henry Member.............................. 32.5

Type section of John Henry Member

[Section 3 (fig. 1) measured westward up small tributary canyon on west side of Smoky Hollow. 

Measurements made on north side of tributary canyon offsetting westward on various prominent sandstone and coal beds. Progressing westward, tributary canyon divides at about 

unit 19, and section goes up north branch ; unit 20 is measured on north side, and higher 

units are measured on south side. North branch of tributary canyon divides again at about 

unit 27, and section goes up northwest side of southwest-heading branch and up prominent 

bluffs to flat top of ridge. Section measured in the SEi/iNW1/! and Wy^NW 1/! sec. 32 and 

sec 31, T. 41 S., R. 4 E., Kane County, Utah]

Straight Cliffs Formation: Thickness 

Drip Tank Member (part) : (feet> 

70. Sandstone, grayish-orange, medium-grained, crossbedded; 

basal 2 ft contains scattered pebbles, bone fragments, 

and small petrified logs; forms cliff.................................... 32.0

Total measured Drip Tank Member................................ 32.0

John Henry Member: 

Upper barren zone:

69. Mudstone, dusky-yellow to light-olive-gray, very thin 

bedded to thin-bedded; contains several thin beds 

of very fine grained sandstone; forms slope.............. 19.0

68. Sandstone, grayish-orange, medium-grained, crossbedded; contains scattered granules and pebbles; 

forms cliff.......................................................................... 39.5

67. Mudstone, dusky-yellow to light-olive-gray, very thin

bedded to thin-bedded; forms slope.............................. 9.0

66. Sandstone, grayish-orange, fine-grained, massive;

rare crossbedding; forms cliff........................................ 19.0

65. Mudstone; same as unit 69................................................ 19.0

64. Sandstone, grayish-orange, fine-grained, crossbedded;

forms cliff.......................................................................... 7.0

63. Mudstone; same as unit 69................................................ 16.0

62. Sandstone; same as unit 64; bedding is slumped near 

top; contains 1-ft-thick mudchip conglomerate lens 

5 ft above base................................................................ 16.0

61. Mudstone; same as unit 69; contains small gray limestone lenses; upper 5 ft has bedding that dips 

about 15°............................................................................ 45.0

60. Sandstone; same as unit 64.............................................. 6.0

59. Mudstone; same as unit 67................................................ 17.0
J22 CONTRIBUTIONS TO STRATIGRAPHY

Type section of John Henry Member Continued

Straight Cliffs Formation Continued

John Henry Member Continued Thickness 

Upper barren zone Continued (feet>

58. Sandstone; same as unit 64; includes some slumped

bedding................................................................................ 21.0

57. Mudstone, carbonaceous, dark-gray to black; contains

a very thin coal bed in middle; forms slope................ 2.0

56. Sandstone; same as unit 58 but medium grained........ 8.0

55. Mudstone; same as unit 69................................................ 14.5

54. Sandstone; same as unit 64; ripple cross-laminated at 

top; contains 2-ft bed of mudstone (same as unit 

67) 2 ft below top...................................................... 16.5

53. Mudstone; same as unit 67; contains minor beds of 

carbonaceous mudstone and a few very thin coal 

beds; forms slope............-.-.....----..........-..--.-..--.-.-..-..-..-.... 18.5

52. Sandstone; same as unit 64 but fine to medium 

grained; contains a 4-ft mudstone bed 25 ft above 

base and a 2-ft mudstone bed (same as unit 67) 

17 ft above base; forms cliff with minor bench 

on top.................................................................................. 38.0

51. Mudstone, same as unit 67; contains a 5-ft sandstone 

bed (same as unit 64) 25 ft above base and a 4-ft 

sandstone bed (same as unit 64) 4 ft above base.... 35.0

Total upper barren zone............................................ 366.0

Rees coal zone:

50. Mudstone, carbonaceous, dark-gray to black; 1.17 ft

thick, underlain by coal 1.83 ft thick; forms slope.. 3.0 

49. Mudstone, carbonaceous, dark-gray to black, very thin

bedded; forms slope..... .............................................. 3.0

Total Rees coal zone.................................................... 6.0

Middle barren zone:

48. Mudstone, dusky-yellow to light-olive-gray, very thin 

bedded to thin-bedded; includes carbonized plant 

twigs and a few thin gray limestone lenses; two 

beds of pale-yellowish-brown fine-grained ripple 

cross-laminated sandstone 3 ft thick occur at top 

and 5 ft above base; forms slope.................................. 31.5

47. Sandstone; same as unit 58; top 3 ft is very thin

bedded................................................................................. 12.0

46. Mudstone; same as unit 67; interbedded with about 

15 percent each of carbonaceous mudstone, sandstone, and very thin coal beds...................................... 5.5

45. Sandstone; same as unit 58.............................................. 14.0

44. Mudstone, same as unit 67; interbedded with about 

30 percent pale-yellowish-brown fine-grained sandstone, 10 percent carbonaceous mudstone, and 10 

percent very thin coal beds............................................ 18.5
NEW MEMBERS, STRAIGHT CLIFFS FORMATION, UTAH J23

Type section of John Henry Member Continued 

Straight Cliffs Formation Continued

John Henry Member Continued Thickness 

Middle barren zone Continued (feet) 

43. Sandstone, pale-yellowish-brown, very fine grained to 

fine-grained, crossbedded; top 3 ft is ripple crosslaminated; contains thin beds of mudstone (same as 

unit 67) in lower 10 ft; forms cliff at top to slope 

at base................................................................................ 16.5

42. Mudstone; same as unit 67................................................ 6.0

Total middle barren zone................................................ 104.0

Christensen coal zone:

41. Coal, black; forms slope.................................................... 7.5

40. Mudstone, carbonaceous, dark-gray to black, very thin

bedded to thin-bedded; forms slope............................ 3.0

39. Sandstone; same as unit 43 but medium-grained grading to fine-grained at top; forms cliff........................ 13.5

38. Mudstone, carbonaceous; same as unit 40; contains 

thick coal beds listed below, several other very thin 

coal beds, and a few gray limestone lenses.

Height above base (ft) Thickness of coal (ft) 

61.7 2.17 

56.0 4.58 

37.5 1.67 

19.5 3.75 

10.0 6.33 (excluding

0.50-ft 

parting) 

1.0 2.42

Thickness of mudstone unit............................................ 73.5

37. Sandstone, pale-yellowish-brown, very fine grained,

laminated; forms cliff...................................................... 7.0

36. Mudstone, carbonaceous; same as unit 40; contains

thick coal beds listed below and several other very

thin coal beds.

Height above base (ft) Thickness of coal (ft)

31.0 6.25 (excluding

0.04-ft 

parting)

16.0 2.0 

13.5 1.08

Thickness of mudstone unit........................................ 39.0

Total Christensen coal zone.................................. 143.5

Lower barren zone:

35. Sandstone, pale-yellowish-brcwn, very fine grained, 

crossbedded, grading to ripple cross-laminated at 

top; forms cliff.................................................................. 12.0

34. Mudstone, carbonaceous; same as unit 40; contains a

very thin coal bed near middle...................................... 17.0

33. Sandstone; same as unit 35; includes some slumped

bedding............................................................................... 8.0

Total lower barren zone............................................ 37.0
J24 CONTRIBUTIONS TO STRATIGRAPHY

Type section of John Henry Member Continued

Straight Cliffs Formation Continued

John Henry Member Continued Thickness 

Lower coal zone: (feet)

32. Mudstone, carbonaceous; same as unit 40; contains 

coal beds listed below and several other very thin 

coal beds, several thin mudstone beds (same as unit 

67) scattered throughout, and several laminated 

sandstone beds (same as unit 37) in lower 20 ft.

Height above base (ft) Thickness of coal (ft) 

73.5 2.17 

64.5 1.42 

47.5 1.00 

43.5 1.25 

5.5 1.33 (excluding

0.25-ft 

parting)

Thickness of mudstone unit........................................ 83.0

31. Sandstone, pale-yellowish-brown (weathers moderate 

brown), fine-grained, irregularly very thin bedded; 

contains finely disseminated carbonaceous material; 

top is well cemented; forms small cliff........................ 1.5

Total lower coal zone.................................................. 84.5

Total John Henry Member........................................ 741.0

Unconformity.

Smoky Hollow Member (part) : 

Calico bed (part) :

30. Sandstone, white to very light gray, medium-grained, 

crossbedded; contains granules and pebbles scattered throughout and small conglomerate lenses; 

cross-stratification at top is truncated by overlying 

unit 31, but there is no relief at the contact; forms 

cliff; only upper part measured.................................... 5.0

Total measured Calico bed.......................................... 5.0

Total measured Smoky Hollow Member.................. 5.0

Type section of Smoky Hollow Member

[Section 2 (fig. 1) measured up the east side of a southeast-trending spur on west side of 

Smoky Hollow in the NEUNE^SWi/i sec. 5, T. 42 S., R. 4 E., Kane County, Utah]

Straight Cliffs Formation: Thickness 

John Henry Member (part) : deet>

29. Sandstone, grayish-orange, medium- to coarse-grained, 

crossbedded; upper 5 ft is very fine grained and ripple 

cross-laminated; contains scattered pebbles and small 

conglomerate lenses near base; this unit is a local fluvial 

channel sandstone bed ; forms slope at top to cliff at base 15.0

Total measured John Henry Member.............................. 15.0
NEW MEMBERS, STRAIGHT CLIFFS FORMATION, UTAH J25

Type section of Smoky Hollow Member Continued

Straight Cliffs Formation Continued

Smoky Hollow Member: Thickness 

Calico bed: (feet)

28. Sandstone, white, coarse-grained, crossbedded; contains scattered pebbles and small conglomerate lenses 

near base; forms cliff...................................................... 5.0

27. Sandstone, white, crossbedded; upper 3 ft is very fine 

grained, grading to siltstone and weathers to a 

slight notch; middle 2 ft is medium grained; basal 

3 ft is mainly a pebble conglomerate; forms cliff...... 8.0

26. Sandstone, white, medium-grained, crossbedded; contains irregular lenses of granule and pebble conglomerate; grades south into dark-gray mudstone; 

forms cliff.......................................................................... 7.0

Total Calico bed.......................................................... 20.0

Barren zone:

25. Interbedded mudstone, dark-gray, and light-gray siltstone; very thin bedded to thin bedded; forms slope.. 5.5 

24. Mudstone, dark-gray; forms slope.................................. 2.0

23. Sandstone, very pale orange, fine-grained, crossbedded

and ripple cross-laminated; forms small cliff............ 1.5

22. Mudstone, medium-gray; forms slope.............................. 2.0

21. Mudstone, dusky-yellow; forms slope.............................. 8.5

20. Sandstone, pale-yellowish-brown (weathers pale 

orange), medium-grained, crossbedded; contains 

scattered granules and pebbles; upper 5 ft is moderate brown and very coarse grained or locally 

dusky yellow green and very fine grained, forms a 

conspicuous dark caprock; unit forms cliff................ 22.0

19. Mudstone, medium-gray to dusky-yellow; contains

small ironstone concretions; forms slope.................... 21.0

18. Sandstone, pale-yellowish-brown (weathers pale 

orange), fine-grained, crossbedded and ripple crosslaminated; contains a 1-ft bed of medium-gray 

mudstone in middle; forms irregular ledge................ 7.0

17. Mudstone, dusky-yellow; forms slope.............................. 1.0

16. Sandstone, pale-yellowish-brown (weathers very pale 

orange), fine-grained, crossbedded; upper 1 ft is 

very fine grained; forms cliff........................................ 7.5

15. Mudstone, dusky-yellow, very thin bedded to thinbedded; forms cliff.......................................................... 4.0

14. Sandstone, grayish-orange, very fine grained, very

thin bedded and ripple cross-laminated; forms ledge 2.5 

Total barren zone........................................................ 84.5

Coal zone:

13. Mudstone, carbonaceous, pale-brown to black; contains several very thin coal beds; forms slope.......... 6.0

12. Coal, black; forms slope...................................................... 1.5
J26 CONTRIBUTIONS TO STRATIGRAPHY

Type section of Smoky Hollow Member Continued

Straight Cliffs Formation Continued Thickness 

Coal zone Continued (feet)

11. Mudstone, carbonaceous, pale-brown, brownish-black,

and grayish-black; forms slope...................................... 4.0

Total coal zone.............................................................. 11.5

Total Smoky Hollow Member.................................... 116.0

Tibbet Canyon Member (part) :

10. Sandstone, very pale orange, medium-grained, thin-bedded

to crossbedded; forms slope....... . ................................... 20.0

Total measured Tibbet Canyon Member.......................... 20.0

Type section of Tibbet Canyon Member

[Section 1 (fig. 1) measured on east side of southeast-trending spur on north side of Tibbet 

Canyon in the N^.NEVlNEVi sec. 14, T. 42 S., R. 3 E., Kane County, Utah]

Straight Cliffs Formation: Thickness 

Smoky Hollow Member (part) : (feet> 

9. Mudstone, carbonaceous, medium-light-gray and brownishblack; contains several very thin coal beds; forms slope.. 4.0

Total measured Smoky Hollow Member... ....................... 4.0

Tibbet Canyon Member:

8. Sandstone, grayish-orange to dark-yellowish-orange, very 

fine grained to medium-grained; irregularly laminated 

to very thin bedded; forms slope.......................................... 1.0

7. Sandstone, grayish-orange (weathers moderate brown), 

medium-grained, crossbedded; basal 0-3 ft is coarse 

grained; form's prominent cliff.............................................. 21.0

6. Sandstone, grayish-orange (weathers moderate brown), 

very fine grained to medium-grained, crossbedded; contains minor amounts of dusky-yellow mudstone laminae 

and very thin beds; forms blocky cliff........... .................... 28.0

5. Sandstone, grayish-orange (weathers moderate brown) ; 

very fine grained but grades to fine grained in upper 

1 ft; crossbedded; forms prominent cliff............................ 14.0

4. Sandstone; same as unit 6 but very fine grained; very thin 

bedded to thick bedded and crossbedded; forms slabby 

cliff............................................................................................... 20.0

3. Mudstone, dusky-yellow, very thin bedded to thin-bedded; 

interbedded with about 30 percent sandstone (same as 

unit 4) ; forms slight notch in cliff........................................ 10.0

2. Sandstone; same as unit 4; interbedded with about 30

percent mudstone (same as unit 3) ; forms slabby cliff.. 10.0

Total Tibbet Canyon Member............................................ 104.0

Total of the four members of the Straight Cliffs

Formation..........................................................................1,102.0
NEW MEMBERS, STRAIGHT CLIFFS FORMATION, UTAH J27

Type section of Tibbet Canyon Member Continued

Tropic Shale (part) : Th$ a 

1. Mudstone, dusky-yellow, very thin bedded; includes several siltstone beds; forms slope........................................... ...................... 50.0

Total measured Tropic Shale...................................................... 50.0

REFERENCES CITED

Cobban, W. A., and Reeside, J. B., Jr., 1952, Correlation of the Cretaceous 

formations of the Western Interior of the United States: Geol. Soc. 

America Bull., v. 63, no. 10, p. 1011-1043.

Dane, C. H., 1960, The boundary between rocks of Carlile and Niobrara age 

in San Juan Basin, New Mexico and Colorado: Am. Jour. Sci., v. 258-A 

(Bradley volume), p. 46-56.

Doelling, H. H., 1967, Kaiparowits Plateau, Garfield County, Utah, EscalanteUpper Valley coal area: Utah Geol. and Mineralog. Survey Spec. Studies 

20, 16 p.

Goddard, E. N., chm., and others, 1963 (reprint), Rock-color chart: New 

York, Geol. Soc. America, 6 p.

Gregory, H. E., and Moore, R. C., 1931, The Kaiparowits region, a geographic 

and geologic reconnaissance of parts of Utah and Arizona: U.S. Geol. 

Survey Prof. Paper 164, 161 p.

Hoyt, J. H., and Weimer, R. J., 1963, Comparison of modern and ancient 

beaches, central Georgia coast: Am. Assoc. Petroleum Geologists Bull., 

v. 47, no. 3, p. 529-531.

Hunt, C. B., assisted by Paul Averitt and R. L. Miller, 1953, Geology and 

geography of the Henry Mountains, Utah: U.S. Geol. Survey Prof. 

Paper 228, 234 p. [1954].

Jacka, A. D., 1965, Depositional dynamics of the Almond Formation, Rock 

Springs uplift, Wyoming, in Wyoming Geol. Assoc. Guidebook 19th 

Field Conf., Sedimentation of Late Cretaceous and Tertiary outcrops, 

Rock Springs uplift, 1965: p. 81-100.

Masters, C. D., 1967, Use of sedimentary structures in determination of 

depositional environments, Mesaverde Formation, Williams Fork Mountains, Colorado: Am. Assoc. Petroleum Geologists Bull., v. 51, no. 10, 

p.2033-2043.

McKee, E. D., 1957, Primary structures in some Recent sediments: Am. Assoc. 

Petroleum Geologists Bull., v. 41, no. 8, p. 1704-1747.

McKee, E. D., and Weir, G. W., 1953, Terminology for stratification and 

cross-stratification in sedimentary rocks: Geol. Soc. America Bull., v. 64, 

no. 4, p. 381-389.
J28 CONTRIBUTIONS TO STRATIGRAPHY

Peterson, Fred, and Waldrop, H. A., 1965, Jurassic and Cretaceous stratigraphy of south-central Kaiparowits Plateau, Utah, in Utah Geol. Soc. and 

Intermountain Assoc. Petroleum Geologists, Guidebook to the geology 

of Utah, no. 19: p. 47-69.

Robison, R. A., 1966, Geology and coal resources of the Tropic area, Garfield 

County, Utah: Utah Geol. and Mineralog. Survey Spec. Studies 18, 

47 p.

Scott, G. R., and Cobban, W. A., 1964, Stratigraphy of the Niobrara Formation at Pueblo, Colorado: U.S. Geol. Survey Prof. Paper 454-L, p. L1-L30.

Thompson, W. 0., 1937, Original structures of beaches, bars, and dunes: 

Geol. Soc. America Bull., v. 48, no. 6, p. 723-752.

O