Cretaceous and Tertiary Paleogeographic 

Reconstructions for the Uinta-Piceance Basin 

Study Area, Colorado and Utah

U.S. GEOLOGICAL SURVEY BULLETIN 1787-Q
AVAILABILITY OF BOOKS AND MAPS OF THE U.S. GEOLOGICAL SURVEY

Instructions on ordering publications of the U.S. Geological Survey, along with the last offerings, are given in the current-year issues of 

the monthly catalog "New Publications of the U.S. Geological Survey." Prices of available U.S. Geological Survey publications released prior 

to the current year are listed in the most recent annual "Price and Availability List." Publications that are listed in various U.S. Geological 

Survey catalogs (see back inside cover) but not listed in the most recent annual "Price and Availability List" are no longer available.

Prices of reports released to the open files are given in the listing "U.S. Geological Survey Open-File Reports," updated monthly, which 

is for sale in microfiche from the U.S. Geological Survey Books and Open-File Reports Sales, Box 25286, Denver, CO 80225.

Order U.S. Geological Survey publications by mail or over the counter from the offices given below.

BY MAIL

Books

Professional Papers, Bulletins, Water-Supply Papers, Techniques of Water-Resources Investigations, Circulars, publications 

of general interest (such as leaflets, pamphlets, booklets), single 

copies of periodicals (Earthquakes & Volcanoes, Preliminary Determination of Epicenters), and some miscellaneous reports, including some of the foregoing series that have gone out of print at the 

Superintendent of Documents, are obtainable by mail from

U.S. Geological Survey, Books and Open-File Report Sales

Box 25286 

Denver, CO 80225

Subscriptions to periodicals (Earthquakes & Volcanoes and 

Preliminary Determination of Epicenters) can be obtained ONLY 

from

Superintendent of Documents

U.S. Government Printing Office

Washington, DC 20402

(Check or money order must be payable to Superintendent of 

Documents.)

Maps

For maps, address mail order to

U.S. Geological Survey, Map Sales

Box 25286 

Denver, CO 80225

Residents of Alaska may order maps from

U.S. Geological Survey, Map Sales

101 Twelfth Ave., Box 12

Fairbanks, AK 99701

OVER THE COUNTER

Books

Books of the U.S. Geological Survey are available over the 

counter at the following U.S. Geological Survey offices, all of 

which are authorized agents of the Superintendent of Documents.

 ANCHORAGE, Alaska-4230 University Dr., Rm. 101

 ANCHORAGE, Alaska-605 West 4th Ave., Rm G-84

 DENVER, Colorado-Federal Bldg., Rm. 169,1961 Stout St.

 LAKEWOOD, Colorado-Federal Center, Bldg. 810

 MENLO PARK, California-Bldg. 3, Rm. 3128,345 

Middlefield Rd.

 RESTON, Virginia-National Center, Rm. 1C402,12201 

Sunrise Valley Dr.

 SALT LAKE CITY, Utah-Federal Bldg., Rm. 8105,125 South 

State St.

 SAN FRANCISCO, California-Customhouse, Rm. 504, 555 

Battery St.

 SPOKANE, Washington-U.S. Courthouse, Rm. 678, West 

920 Riverside Ave.

 WASHINGTON, D.C.-U.S. Department of the Interior Bldg., 

Rm.2650,1849CSt.,NW.

Maps

Maps may be purchased over the counter at the U.S. Geological Survey offices where books are sold (all addresses in above list) 

and at the following Geological Survey offices:

 ROLLA, Missouri-1400 Independence Rd.

 FAIRBANKS, Alaska-New Federal Building, 101 Twelfth 

Ave.
Chapter Q

Cretaceous and Tertiary Paleogeographic 

Reconstructions for the Uinta-Piceance Basin 

Study Area, Colorado and Utah

By K.J. FRANCZYK, T.D. FOUCH, R.C. JOHNSON, 

C.M. MOLENAAR, and W.A. COBBAN

A multidisciplinary approach to research studies of sedimentary 

rocks and their constituents and the evolution of sedimentary basins, 

both ancient and modern

U.S. GEOLOGICAL SURVEY BULLETIN 1787

EVOLUTION OF SEDIMENTARY BASINS UINTA AND PICEANCE BASINS
U.S. DEPARTMENT OF THE INTERIOR 

MANUEL LUJAN, JR., Secretary

U.S. GEOLOGICAL SURVEY 

Dallas L. Peck, Director

Any use of trade, product, or firm names in this publication is for descriptive 

purposes only and does not imply endorsement by the U.S. Government

UNITED STATES GOVERNMENT PRINTING OFFICE: 1992

For sale by the

Book and Open-File Report Sales

U.S. Geological Survey

Federal Center

Box 25425

Denver, CO 80225

Library of Congress Cataloging-in-Publication Data

Cretaceous and Tertiary paleogeographic reconstructions for the Uinta-Piceance 

basin study area, Colorado and Utah / by K.J. Franczyk ... [et al.].

p. cm. (Evolution of sedimentary basins Uinta and Piceance Basins ; 

ch. Q) (U.S. Geological Survey bulletin ; 1787-Q)

"A multidisciplinary approach to research studies of sedimentary rocks and 

their constituents and the evolution of sedimentary basins, both ancient and 

modern."

Includes bibliographical references.

Supt. of Docs, no.: I 19.3:1787-Q

1. Paleogeography Uinta Basin (Utah and Colo.). 2. Paleogeography 

Colorado Piceance Creek Basin. 3. Geology, Stratigraphic Cretaceous. 

4. Geology, Stratigraphic Tertiary. 5. Geology, Structural Uinta Basin 

(Utah and Colo.). 6. Geology, Structural Colorado Piceance Creek Basin. 

7. Uinta Basin (Utah and Colo.). 8. Piceance Creek Basin (Colo.). 

I. Franczyk, Karen J. II. Series. III. Series: U.S. Geological Survey bulletin ; 

1787-Q.

QE75.B9 no. 1787-Q 

[QE501.4.P3] 

557.3 s dc20

[551.7'7'09788] 90-21568

CIP
CONTENTS

Abstract Ql

Introduction Ql

Acknowledgments Q4

Methods Q4

Paleogeographic reconstructions Q4

Early Cenomanian Neogastroplites americanus faunal zone Q4 

Early Turonian Vascoceras birchbyi faunal zone Q8 

Late middle Turonian Prionocyclus hyatti faunal zone Q9 

Middle Coniacian Inoceramus deformis faunal zone Qll 

Late Santonian Desmoscaphites bassleri faunal zone Q12 

Early Campanian Scaphites hippocrepis I faunal zone Q13 

Late early Campanian Baculites mclearni faunal zone Q14 

Early late Campanian Baculites asperiformis faunal zone Q15 

Middle late Campanian Baculites perplexus faunal zone Q17 

Late late Campanian Exiteloceras jenneyi faunal zone Q18 

Early Maastrichtian Baculites reesidei faunal zone Q19 

Middle Maastrichtian Baculites clinolobatus faunal zone Q21 

Late Maastrichtian Q22 

Middle Paleocene Q23 

Early late Paleocene Q23 

Early Eocene Q26 

Middle Eocene Q28 

Late Eocene Q29 

Latest Eocene and (or) earliest Oligocene Q29

Summary Q31

References cited Q33

FIGURES

1. Location map of the Uinta-Piceance basin study area Q2

2. Stratigraphic cross section of Cretaceous rocks from central Utah to 

northeastern Colorado Q3

3. Chart showing molluscan fossil zones for the Upper Cretaceous, Western 

Interior of the United States Q5

4. Generalized geologic map of the study area, showing distribution of Cretaceous

and Tertiary sedimentary rocks and Tertiary igneous rock Q6 

5-24. Paleogeographic reconstruction maps showing time of:

5 Early Cenomanian Neogastroplites americanus faunal zone Q8

6. Early Turonian Vascoceras birchbyi faunal zone Q9

7. Late middle Turonian Prionocyclus hyatti faunal zone Q10

8. Middle Coniacian Inoceramus deformis faunal zone Qll

9. Late Santonian Desmoscaphites bassleri faunal zone Q12

10. Early Campanian Scaphites hippocrepis I faunal zone Q14

11. Late early Campanian Baculites mclearni faunal zone Q15

12. Early late Campanian Baculites asperiformis faunal zone Q16

13. Middle late Campanian Baculites perplexus faunal zone Q17

Contents III
14. Late late Campanian Exiteloceras jenneyi faunal zone Q18

15. Early Maastrichtian Baculites reesidei faunal zone Q20

16. Middle Maastrichtian Baculites clinolobatus faunal zone Q21

17. Late Maastrichtian Q22

18. Middle Paleocene Q24

19. Early late Paleocene Q25

20. Early Eocene Q26

21. Middle Eocene (time 1) Q28

22. Middle Eocene (time 2), representing Lake Uinta's phase of maximum 

expansion that included the Mahogany oil-shale bed deposition Q30

23. Late Eocene Q31

24. Latest Eocene and (or) early Oligocene Q32

25. Chart showing structural and depositional events in the study area from late 

Early Cretaceous to late Oligocene time Q33

TABLE

1. Lithologies corresponding to depositional environments in each of the three major 

depositional settings within the study area Q7

CONVERSION FACTORS FOR SOME SI METRIC AND U.S. UNITS OF MEASURE

____To convert from______________To_________________Multiply by_____

Feet (ft) Meters (m) 0.3048

Miles (mi) Kilometers (km) 1.609

Pounds (Ib) Kilograms (kg) 0.4536

Degrees Fahrenheit (°F) Degrees Celsius (°C) Temp °C=(temp °F-32)/l .8

IV Contents
EVOLUTION OF SEDIMENTARY BASINS UINTA AND PICEANCE BASINS

Cretaceous and Tertiary Paleogeographic 

Reconstructions for the Uinta-Piceance Basin 

Study Area, Colorado and Utah

By KJ. Franczyk, T.D. Fouch, R.C. Johnson, C.M. Molenaar, and W.A. Cobban

Abstract

Paleogeographic reconstructions for early Late Cretaceous through early Oligocene time in the Uinta-Piceance 

basin study area illustrate the major changes that accompanied 

incursion of the Cretaceous sea, tectonism in the Sevier thrust 

belt, eustatic changes, break-up of the foreland, intermontane 

basin formation, and establishment and demise of large lacustrine complexes. Throughout most of the Late Cretaceous, the 

study area was part of the foreland basin in which depositional 

patterns were controlled primarily by both tectonism in the 

Sevier thrust belt and eustatic changes. In late Campanian 

time, the gradual withdrawal of the Cretaceous sea from the 

western part of the study area coincided with a decrease in 

subsidence rates in areas closest to the thrust belt. Both events 

resulted in broader nonmarine depositional areas than had 

existed previously for much of the Late Cretaceous. Subsequently in the west-central and southwestern part of the 

study area, late-stage, thin-skinned thrusting in the Sevier belt 

resulted in the formation of small intermontane basins (piggyback basins) on top of the thrust allochthon in what had 

previously been part of the foreland. Shortly thereafter, in latest 

Campanian or earliest Maastrichtian time, basement-involved 

uplift of the San Rafael structure created both a new intermontane basin between it and the thrust belt and a broad, 

nonsubsiding region in the south-central part of the study 

area. Concurrently, thin-skinned thrusting continued in the 

northwestern part of the study area.

By late Maastrichtian time, the sea had completely 

withdrawn from the study area, movement on the Uinta and 

Sawatch uplifts was initiated, and deposition was restricted to 

a few small intermontane basins in the western part of the 

study area. Basement-involved uplifts continued to develop 

and depositional areas remained restricted into the middle 

Paleocene. The intermontane basins that characterized much

Manuscript approved for publication July 30, 1990.

of the Paleogene formed by middle Paleocene time, and 

deposition occurred primarily in alluvial, wetland, and 

shallow lacustrine environments. Although the wetland and 

shallow lacustrine depositional areas expanded greatly in late 

Paleocene time, it was not until the early Eocene that 

regionally extensive lakes formed in both the Uinta and 

Piceance basins. These two lakes expanded and formed a 

single large lake in middle Eocene time. Shortly thereafter, 

clastic influx from the north, which included abundant 

reworked volcanic sediments, began to fill in the Piceance 

basin and displace the lake westward. The lake continued to 

shrink and retreat westward during the late Eocene and finally 

disappeared in latest Eocene or earliest Oligocene time. The 

presence of tuff beds in these youngest lacustrine deposits 

indicates continued volcanism, probably from sources both 

outside of and in the westernmost part of the study area. The 

Uinta basin was filled with elastics shed during the final 

tectonic event in the Uinta uplift; concurrently, volcanic 

deposits and reworked volcanic detritus accumulated in the 

western part of the study area.

INTRODUCTION

This report presents our synthesis of the geologic 

history during the Late Cretaceous and Paleogene in an area 

including and surrounding the Uinta and Piceance basins. 

This study was conducted as part of the U.S. Geological 

Survey's Evolution of Sedimentary Basins Program, whose 

objective is an interpretation of the Phanerozoic history of 

selected energy-resource-rich basins. Because the extent of 

Tertiary deposits is generally used to define the present 

Uinta and Piceance basins, the basin study area boundaries 

encompass a much larger area in order to reconstruct the 

regional history prior to the Tertiary. Our map area (fig. 1) 

corresponds to the base map for the Uinta and Piceance 

basin study area, which enables us to illustrate regional 

variations in depositional environments and tectonic

Paleogeographic Reconstructions, Colorado and Utah Q1
113°

41°

. Salt Lake > ^U i n t at- } », jT-^f

 rl

20 40 60 MILES

n i

50 100 KILOMETERS

j1

WYOMING

UTAH

k^J

^ STUDY 

AREA

COLORADO

Figure 1. Location map of the Uinta-Piceance basin study area, Utah, Colorado, and Wyoming.

activity. Detailed discussions of the depositional history, 

particularly for the Tertiary, in the northernmost part of the 

map area are beyond the scope of this report.

To portray the evolution of the Cretaceous and 

Tertiary terrane, we reconstructed the paleogeography of the 

study area for 17 time intervals, 12 of which are based on 

well-established marine faunal zones. The reconstructions 

cover early Late Cretaceous through early Oligocene time. 

Because Lower Cretaceous strata in the study area are 

poorly constrained with respect to age and extent and 

because post-early Oligocene age deposits are restricted, 

these sequences were excluded from our study. Figure 2, a 

west-to-east stratigraphic cross section of Cretaceous rocks 

within and east of the study area, shows the thicknesses and 

regional relations of many of the units that are on the 

paleogeography maps.

Our reconstructions represent both a synthesis of the 

literature and the incorporation of recent paleontologic and 

sedimentologic data as well as new tectonic interpretations 

and stratigraphic correlations. Reconstructions for earliest

Late Cretaceous, latest Cretaceous, and earliest Tertiary 

time contain major revisions from previous work. It is 

beyond the scope of this report to cite the large volume of 

literature that exists on the Cretaceous and Tertiary strata in 

the study area. The references cited herein represent our 

principal sources for ideas and information used in this 

study.

Changes in the paleogeography through the Late 

Cretaceous and early Tertiary were accompanied by paleoclimatic changes. Except for parts of the Eocene (MacGinitie, 1969), detailed paleoclimatic reconstructions for this 

study area are lacking. Regional paleoclimatic reconstructions for the Late Cretaceous and early Tertiary in low 

to middle latitudes in the Western Interior (Wolfe and 

Upchurch, 1987) indicate that the Late Cretaceous was 

characterized by a warm, subhumid climate. Temperatures 

declined slightly in the Campanian and early Maastrichtian 

and increased again in the latest Maastrichtian. A change to 

a wetter climate marked the onset of the Tertiary. A warm, 

humid climate persisted into the early Eocene, and the early

Q2 Evolution of Sedimentary Basins Uinta and Piceance Basins
ww- 800 KILOMETERS (500 MILES) -HE

I 8

1£

oio

Q. 

C

North plunge of 

SAN RAFAEL UPLIFT

UTAH

BOOK CLIFFS

COLORADO

WHITE RIVER UPLIFT 

(section projected)

FRONT RANGE UPLIFT 

(section restored)

DENVER BASIN

WASATCH 

PLATEAU

W E

Probable horizontal shortening due to 

folding and thrusting

|-*-U- Autochthonous Larimer and Rocky Ridge 

Sandstone Members

Farrer tf ^^^^ZSE2!3S=^Hf 

Formations -r^O 7^7 ~ ^><K 2 ^ .*- T''" '" -"- ^-<.jAgf***"1""-^ 

AAAA

TERTIARY

1

Campanian

San.

Tijr.

Cen.

Alb.

UPPER CRETACEOUS

L.CRET. 

(part)

ivalent

METERS FEET 

- 3,000

1 of Indianola Group

2 of Mt. Garfield Formation

KsxKfvKavKspKrKcz

Kco

Sixmile Canyon Formation Funk Valley Formation 

Alien Valley Shale 

Sanpete Formation Rollins Sandstone Member Cozzettc Sandstone Member Corcoran Sandstone Member

EXPLANATION

Nonmarine rocks

Marine and coastal-barrier sandstone

Marine shale and siltstone

I

SaltLakeCity w ?LUTAH

Denver

-E

Line of section

COLORADO

600 - 400200 

2,000

Calcareous shale 

Limestone 

Conglomerate 

Approximate time lineUnconformity Queried where 

extent uncertain

0 

VERTICAL EXAGGERATION si 51

Figure 2. Stratigraphic cross section of Cretaceous rocks across the study area and into the Denver Basin in northeastern Colorado. Thicknesses are based 

on well and outcrop control. The paleogeographic maps in this report do not include area east of the White River uplift.
Eocene was probably wanner than the Late Cretaceous 

(Wolfe and Upchurch, 1987). An overall cooling and drying 

trend with minor climatic fluctuations marked the remainder 

of the Eocene (G.R. Upchurch, oral commun., 1990).

ACKNOWLEDGMENTS

This work was conducted under the U.S. Geological 

Survey Evolution of Sedimentary Basins Program in 

conjunction with the Utah Geological and Mineralogical 

Survey. We greatly appreciated and relied on the discussions and reviews by numerous people who have worked in 

this area, particularly Bruce Bryant, William B. Cashion, 

William A. Cobban, John R. Dyni, Richard M. Forester, 

Timothy F. Lawton, E. Alien Merewether, Douglas J. 

Nichols, and Fred Peterson.

METHODS

Most of the Cretaceous time intervals used in the 

reconstructions correspond to a reference faunal zone for 

the Western Interior (fig. 3). These intervals are not equally 

spaced throughout the Late Cretaceous. Rather, these 

particular intervals are used because either they correspond 

to most of the transgressive and regressive maxima within 

the study area or they correspond to times of significant 

paleogeographic changes resulting from tectonism. During 

latest Cretaceous and early Tertiary time, nonmarine rocks 

predominate; these are dated by using palynomorph, ostracode, charophyte, and mollusk assemblages. The age 

resolution obtained from using these paleontologic materials is not as great as that provided by marine mollusks, so 

much broader intervals (such as late Paleocene) are used. 

Middle Eocene through Oligocene rocks contain tuffaceous 

beds that are radiometrically dated.

The base map area, which includes parts of northwestern Colorado, northeastern Utah, and the southernmost 

edge of Wyoming, encompasses about 222,000 km2 (square 

kilometers). Figure 4 is a generalized geologic map showing 

the distribution of Cretaceous and Tertiary outcrops in this 

area. The geologic map can be compared to the paleogeographic maps to identify areas where the reconstructions 

have been made by interpolating between outcrops. Because 

drill holes have not penetrated the Cretaceous section in a 

large part of the Uinta basin, the paleogeographic interpretations are speculative, but they are consistent with 

regional relations. Locally, and particularly in the southern 

and western parts of the map area, the limits of Tertiary 

deposition are unknown because of extensive erosion.

The exact locations, extent, and relief of the highlands 

are difficult to determine because their positions are approximated from inferred associations with wedges of coarse 

detritus that we believe were derived from them. The age,

extent, and stratigraphic identity of these poorly exposed 

conglomeratic nonmarine units, in turn, are generally poorly 

constrained.

Because detailed paleogeographic reconstructions are 

only locally possible, the paleogeographic subdivisions are 

generalized. These subdivisions are highlands, alluvial fan, 

alluvial plain, coastal plain, open marine, lacustrine, marginal lacustrine, and wetlands. Lithofacies provide the basis 

for determining the paleogeographic subdivisions. In order 

to relate the paleogeography to the rock record, table 1 lists 

the lithologies that correspond to particular depositional 

environments within the three depositional settings that 

occurred in the study area during the Late Cretaceous and 

the Paleogene. Patterns are used on the map figures to 

delineate the subdivisions, and except for the position of the 

marine shoreline, the boundaries are gradational. Some 

areas, especially those within intermontane basins, may be 

characterized by a mixture of depositional environments; 

these are portrayed schematically on the maps.

In some reconstructions, highlands patterns are 

differentiated to indicate (1) high to moderate relief, 

(2) moderate to low relief, and (3) low relief. These terms 

are relative; quantitative limits are not suggested. Based on 

the grain size and distribution of detritus shed from these 

uplifts, the relief of the uplifts varied greatly. During latest 

Cretaceous and early Tertiary time, large areas apparently 

either were not subsiding or were slightly positive but 

supplying little or no sediment. These areas are difficult to 

distinguish from areas of low relief; therefore, on the 

paleogeography maps, the symbol for low-relief highlands 

is also used for these nonsubsiding areas. The area west of 

a line extending from approximately the southwest corner of 

Wyoming through Salina, Utah, is presently allochthonous 

terrain, that is, most pre-Paleocene rocks have been transported east as thrust sheets. For Cretaceous reconstructions 

in this area, the paleogeography is restored 5 to 65 kilometers to the west to allow for thrust displacement.

Stratigraphic nomenclature is not a primary focus in 

these reconstructions. For reference, the units that formed in 

the various depositional environments are listed with that 

environment on the paleogeography maps. Units that are of 

several ages generally appear on more than one paleogeographic map. Stratigraphic nomenclature is also used in 

the text to help elucidate problems such as in correlation, 

age, and depositional origin that create uncertainties in the 

reconstructions.

PALEOGEOGRAPHIC RECONSTRUCTIONS

Early Cenomanian

Neogastroplites americanus Faunal Zone

The first incursion of the shallow, epicontinental 

Cretaceous sea into the map area occurred during the early

Q4 Evolution of Sedimentary Basins Uinta and Piceance Basins
Ma

66-

67-

68-

69-

70-

71-

72-

73-

74-

75-

76-

77 -

78-

79 -

80-

81 -

82-

83-

84 

85-

86 -

87-

RR

CO

UJ

rr

UJ

CO

 ~;

CC 

Q.

ID

0

LU

(J

LU

rr 

u

rr

LU

0. 

CL

ID

STAGE

z

p

0 

CC

<

^

CAMPANIAN

SANTONIAN

_l LLJ

< (D

§k

II ^P

-r D

 CO

upper

lower

upper

middle

lower

WESTERN INTERIOR

MOLLUSCAN

FOSSIL ZONES

65 Discoscaphites cheyennensis, 

D. nebrascensis

64 Discoscaphites roanensis, 

Hoploscaphites nicolleti

if 63 Hoploscaphites aff.H. nicolleti,

Sphenoaiscus (Coahuilites) 

62 Baculites clinolobatus

* 61 Baculites grandis

* 60 Baculites baculus

59 Baculites eliasi

58 Baculites jenseni

57 Baculites reesidei

56 Baculites cuneatus

 k 55 Baculites compressus

54 Didymoceras cheyennense 

* 53 Exiteloceras jenneyi 

52 Didvmoceras stetiensoni 

* 51 Didpmoceras nebrascense

50 Baculites scotti

49 Baculites reduncus

48 Baculites gregoryensis

47 Baculites perplexus (late form)

46 Baculites gilberti

45 Baculites perplexus (early form)

44 Baculites sp. (smooth)

43 Bacu/ites asperiformis

42 Baculites mclearni

* 41 Bacu/ites obtusus

* 40 Bacu/ites sp. (weak flank ribs)

39 Bacu/ites sp. (smooth)

38 Scaphites hippocrepis III

37 Scaphites hippocrepis II

36 Scaphites hippocrepis 1

it 35 Desmocaphites bassleri

34 Desmocaphites erdmanni

33 Clioscaphites choteauensis

32 Clioscaphites vermiformis

31 Clioscaphites saxitonianus

30 /noc. undu/atop/icatus

Via

OO

90 -

91 -

92 -

93 -

94 -

95 -

96 -

97 -

98 -

|SERIES 

CO

a.

'ACEOUS I

i 

LU

rr 

u 

rr

LU 

CL 

QSTAGE

CONIACIAN

TURONIAN

CENOMANIAN

INFORMAL SUBSTAGE

upper

middle

lower

upper

middle

lower

upper

middle

lower

WESTERN INTERIOR 

MOLLUSCAN 

FOSSIL ZONES

29 Scaphites depressus

28 Scaphites uentricosus 

* 27 Inoceramus deformis 

26 Inoceramus erectus

25 Prionocyc/us quadratus

24 Scaphites whitfieldi

23 Scaphites warreni

22 Prionocyc/us macombi 

21 Prionocyc/us hyatti

20 Prionocyc/us percarinatus

19 Co//ignoniceras woollgar. 

18 Mammites nodosoides 

17 Vascoceras birchbyi 

16 Pseudaspidoceras flexuosum

* 15 Neocardioceras juddii

14 Burroceras clydense

13 Sciponoceras graci/e 

12 Metoicoceras mosbyense

 fr 1 1 Duntieganoceras pondi 

1 0 P/esiacan thoceras

luyomingense

* 9 Acanthoceras amphibo/um

8 Acanthoceras mu/doonense

7 Acanthoceras granerosense

6 Con/inoceras tarrantense

5 Neogastrop/ites mclearni

4 Neogastrop/ites muelleri

3 Neogastrop/ites americanus

* 2 Neogastrop/ites cornutus

1 Neogastrop/ites haasi

Figure 3. Molluscan fossil zones for the Upper Cretaceous, Western Interior of the United States, modified (W.A. Cobban, 

written commun., 1989) from Molenaar and Cobban (1991) and Fouch and others (1983). Stars indicate sequential location 

of rocks radiometrically dated by Obradovich and Cobban (1975) and by J.D. Obradovich (oral commun., 1989).

Paleogeographic Reconstructions, Colorado and Utah Q5
0 20 4C 60 MILES

0 50 100 MILES

EXPLANATION

Tertiary rock

Tertiary volcanic and intrusive rock 

Cretaceous rock

Pre-Cretaceous and post-Tertiary rock 

Dominantly pre-Cretaceous rock; Quaternary 

deposits abundant in western map area

Figure 4. Generalized geology of the study area, showing distribution of Cretaceous and Tertiary sedimentary rocks and 

Tertiary igneous rock. (Modified from Oetking and others, 1967, and Renfro and Feray, 1972.) Distribution of outcrop areas 

indicates extent of surface control. Subsurface control of Cretaceous rocks is limited throughout much of the Uinta basin 

where these rocks are deeply buried.

Cenomanian. Figure 5 shows the paleogeography at the 

maximum point of the sea's transgression when a dominantly northwesterly trending shoreline was established 

across the central part of this area. The offshore marine 

deposits of the Mowry Shale grade southwestward into the 

nearshore marine deposits of the Dakota Sandstone, which 

in turn grades into mud-dominated, nonmarine deposits of 

the Cedar Mountain Formation. A coastal-plain environment was probably present landward of the Mowry 

shoreline, but it is non-coal bearing and difficult to separate 

from the mud-rich alluvial-plain environment. The Cedar 

Mountain grades westward into the coarser grained alluvial

plain deposits of the lower part of the Indianola Group 

(Witkind and others, 1986).

The Mowry Shale was previously considered to be of 

late Albian age. However, Cobban and Kennedy (1989) 

correlated Metengonoceras from the Mowry to those found 

in known lower Cenomanian rocks in the Gulf Coast area; 

therefore, they interpreted the Mowry Shale to be of early 

Cenomanian age. The radiometric age of the Mowry 

remains the same (96-98.6 Ma; Obradovich and Cobban, 

1975, and J.D. Obradovich, oral commun., 1989) inasmuch 

as these ages were based on radiometric ages of bentonite 

beds within the Mowry.

Q6 Evolution of Sedimentary Basins Uinta and Piceance Basins
Table 1. Lithologies corresponding to depositional environments in each of the three major depositional 

settings within the study area

Depositional 

setting

Depositional 

environment Lithologic record

Marine Alluvial fan................................. Sheet and channel-form conglomerate; less abundant pebbly

foreland basin. sandstone and sandstone; rare siltstone and mudstone.

Alluvial plain.............................. Sheet to lenticular sandstone and pebbly sandstone; common to abundant siltstone and mudstone; common 

organic debris.

Coastal plain................................ Lenticular to tabular sandstone encased in siltstone, mudstone, and claystone; abundant to common coal beds and 

carbonaceous shale; abundant to common organic debris.

Nearshore and coastal marine .... Coarsening-upward, sheet to tabular sandstone; interbedded

sandstone and mudstone in lower part; common organic 

debris; common marine fossils and trace fossils.

Offshore marine.......................... Dark-gray siltstone, mudstone, and claystone; local calcareous mudstone and limestone; local channel-form and 

sheet sandstone encased in fine-grained rocks; common to 

_____________ abundant marine fossils and trace fossils.________

Intermontane Alluvial fan................................. Same as in marine foreland basin but red beds common to

basins. abundant.

Alluvial plain .............................. Same as in marine foreland basin but red beds common to

abundant; calcareous; variegated mudstone and claystone; 

common pedogenic carbonate nodules; rare organic 

debris. 

Wetland....................................... Calcareous mudstone and claystone; locally common

organic debris; pedogenic features common; common to 

rare fossils; thin carbonate beds. 

Shallow lacustrine....................... Dominantly gray calcareous claystone and carbonate rocks;

less abundant fine-grained sandstone; abundant to 

common fossils including charophytes, ostracodes, gastropods, and mollusks; locally common to abundant 

organic debris.

Marginal lacustrine includes Dominantly gray to tan interbedded sandstone, siltstone, 

deltaic, delta plain, mudflat, calcareous mudstone, and carbonate rocks; common to 

paludal, and nearshore lacus- abundant pisoliths, oolites, and stromatolites; locally 

trine settings. common fossils and organic debris. 

Lacustrine includes nearshore Organic-rich calcareous claystone and mud-supported carand open lacustrine settings. bonate rocks; less abundant very fine grained sandstone

and siltstone; abundant algal material; disseminated and 

bedded saline minerals.

Volcanicdominated 

terrain.

Volcanic

Alluvial fan and plain................

Wetland and shallow lacustrine.

Flows; flow breccias, lahars, tuffs, and tuffaceous sedimentary rocks.

Conglomerate, sandstone, siltstone, and mudstone composed of volcaniclastic and siliciclastic material.

Variegated mudstone, carbonate rocks, fine-grained sandstone, and siltstone; abundant volcaniclastic material; rare 

plant fossils.

An erosional event subsequent to this phase of early 

Cenomanian deposition resulted in an unconformity that 

separates the Mowry Shale from the overlying upper middle 

Turonian shale of the Frontier Formation on the north side 

of the Uinta basin. The name Dakota Sandstone has been 

applied to a sandstone that crops out on the north side of the 

Uinta basin. This Dakota is of Albian age and is 4-6 m.y. 

older than a middle and late Cenomanian-age unit that crops 

out south of the Uinta basin and is also assigned to the 

Dakota Sandstone. The facies changes between the early

Cenomanian Mowry, Dakota, and Cedar Mountain occur in 

the subsurface in the Uinta basin. Where the Cedar Mountain Formation crops out in the San Rafael Swell area, 

palynomorphs recovered from the uppermost part of this 

unit indicate an Albian age (Tschudy and others, 1984). 

This palynomorph assemblage does not contain species that 

are found in Mowry-equivalent rocks (DJ. Nichols, oral 

commun., 1990). If part of the Cedar Mountain Formation 

formed in early Cenomanian time, as shown in figure 5, 

then either palynomorphs of this age have not yet been

Paleogeographic Reconstructions, Colorado and Utah Q7
113

40'

A - : - v.frr \c:i^:i.-^r^T ~

/X 0.0-'#*::\ VX^fSZZlSlI _^ :^fevW^^=

^ . ^Pe!^--:V^l): '^^/r%;. 

 6 9X::#ti&£&fc!

0 20 40 60 MILES

0 50 100 KILOMETERS

EXPLANATION 

Nondepositional areas

High to moderate relief Lacustrine

Depositional areas 

Alluvial fan 

Alluvial plain

Coastal plain

Marine nearshore sand

Marine offshore mud

Shoreline Queried where 

extent uncertain

Figure 5. Paleogeographic reconstruction during the early Cenomanian Neogastroplites americanus faunal zone. Relations of the 

Dakota Sandstone, Mowry Shale, and the upper parts of both the Cedar Mountain and Burro Canyon Formations are based on 

Molenaar and Cobban (1991). Dashed line marks approximate boundary east of which alluvial plain is mud dominated.

recovered or the early Cenomanian part was eroded during 

formation of the unconformity that separates the Cedar 

Mountain from the overlying middle to late Cenomanianage Dakota Sandstone in the San Rafael Swell area.

Eariy Turonian

Vascoceras birchbyi Faunai Zone

The sea transgressed far into central Utah during this 

time, and the dominantly north trending coastline that

characterized the study area for most of the Late Cretaceous 

was established (fig. 6). Although this faunal zone coincided more closely with the maximum transgression of the 

sea farther south in Arizona and New Mexico (Molenaar, 

1983), the maximum transgression of the sea in most of the 

map area occurred later, during the early part of the 

Collignoniceras woollgari faunal zone (earliest middle 

Turonian). However, in the southwestemmost part of Utah, 

the maximum transgression of the sea was during the late 

Cenomanian Sciponoceras gracile faunal zone (Cobban and 

Hook, 1984).

Q8 Evolution of Sedimentary Basins Uinta and Piceance Basins
113° 112° 110° 109° 108° 107°

0 50 100 KILOMETERS

EXPLANATION 

Nondepositional areas

Coastal plain 

Marine nearshore sand 

Marine offshore mud 

Marine offshore carbonate mud 

Shoreline

High to moderate relief 

Depositional areas 

Alluvial fan 

Alluvial plain

Figure 6. Paleogeographic reconstruction during the early Turonian Vascoceras birchbyi faunal zone. Boundaries of subdivisions 

within the marine area are modified from Merewether and Cobban (1986) in Colorado and eastern Utah and from Molenaar and 

Cobban (1991). Unpatterned area to right of dashed line is an offshore shoal or low-relief island; in this area, rocks of this age are 

absent owing to pre-middle or pre-late Turonian erosion.

During the time of the Vascoceras birchbyi faunal 

zone and ranging down into the Cenomanian, a large 

offshore shoal or low-relief island existed in northeastern 

Utah and northwestern Colorado, according to the interpretation of Molenaar and Cobban (1991). This passive 

positive area was onlapped by upper Cenomanian through 

lower middle Turonian marine deposits and finally covered 

by upper middle Turonian marine deposits. Molenaar 

and Cobban (1991) have shown a lithofacies map for 

the early middle Turonian faunal zone of Collignoniceras woollgari that coincides with part of our map 

area.

Late Middle Turonian 

Prionocyclus hyatti Faunal Zone

The first major regression of the sea started probably 

in early middle Turonian time in the far western and 

northwestern parts of the map area, but in most of this area 

the sea regressed during late middle Turonian time (fig. 7).

Paleogeographic Reconstructions, Colorado and Utah Q9
;; i 1 ; j; jj^^^i^jgiir^ J__ _

v£&^<:f t '

Mqmcosj Shale (part)F

0 20 40 60 MILES

0 50 100 KILOMETERS 

EXPLANATION

Nondepositional areas 

High to moderate relief

Depositional areas 

Alluvial fan 

Alluvial plain XX

Coastal plain 

Marine nearshore sand 

Marine offshore mud 

Offshore shallow-marine sand 

Shoreline

Figure 7. Paleogeographic reconstruction at maximum extent of regression during the late middle Turanian Prionocyclus hyatti 

faunal zone. Boundaries in Colorado and eastern Utah are modified from Merewether and Cobban (1986). Unpatterned area to 

right of dashed line may be an offshore shoal or low-relief island; in this area, rocks of this age are absent owing to pre-late 

Turanian erosion.

The shoreline prograded far to the east in northern Utah 

producing a northeast-trending shoreline through that area. 

The shoreline trend becomes more northerly in southernmost Wyoming (Merewether and others, 1983; Merewether 

and Cobban, 1986). Strata of this age are missing from the 

unpatterned area that represents an offshore shoal or lowrelief island in the eastern part of the area of figure 7. 

Whether this missing interval is due to nondeposition on an

offshore shoal or to erosion is uncertain; erosion was 

occurring in other parts of the Western Interior at this time. 

Weimer and Sonnenberg (1983) showed erosion of upper 

middle Turanian rocks under the Niobrara Formation in 

northeastern Colorado. Molenaar and Cobban (1991) have 

shown lithofacies maps, which coincide with part of our 

map area, for both this faunal zone and the early late 

Turanian faunal zone of Prionocyclus macombi.

Q10 Evolution of Sedimentary Basins Uinta and Piceance Basins
113' 107°

Mg-r!'\ : :- .-' v > ylMancos Group (pa

A *pii

0 20 40 60 MILES

0 50 100 KILOMETERS

EXPLANATION 

Nondepositional areas

Coastal plain 

Marine nearshore sand 

Marine offshore mud 

Marine offshore carbonate mud 

Shoreline

High to moderate relief 

Depositional areas 

Alluvial fan 

Alluvial plain

Figure 8. Paleogeographic reconstruction during the middle Coniacian Inoceramus deformis faunal zone. Boundary in western 

Colorado between marine siliciclastic mud and marine carbonate mud is modified from Merewether and Cobban (1986).

Middle Coniacian

Inoceramus deformis Faunal Zone

A major westward transgression of the sea occurred at 

this time. As shown in figure 8, the marine shoreline was 

near the highlands of the Sevier thrust belt. This relation 

gave rise to a narrow band of nonmarine rocks representing 

thick sequences of coarse-grained sediments that were 

deposited in a north-trending zone undergoing rapid basinfloor subsidence adjacent to the rising highland. The 

locations of most nonmarine boundaries are uncertain 

owing to few exposures and postdepositional deformation. 

A well-defined coastal-plain zone may have only existed 

locally through the map area at this time, possibly because 

of the narrow depositional belt between the highlands and 

the sea.

In the Henry basin area (between the Henry 

Mountains and the Circle Cliffs uplift on fig. 1) lies an

Paleogeographic Reconstructions, Colorado and Utah Q11
113°_____^___

A A \A

112°

~£< OP.n^

110° 109° 108° 107°

41° I- /\ \ ' /\ /' ^ 0.".|£.

x A 'o-^T^.^fe

A \ /o"^? ^-EPjiP;Ca^yb'ii::;V-r;:'

A A &fi^-'$iji3^rf\ty$£&:&'' 

/\ cfe ;fli:^;;ii;Ni;i;i;;ii^:: \

A

40°

10-:--

A A^a

39°

z>

A 

A~

A A 

A

O o-.g.o-mm ^^ fm<^m

*-.:-;:^^0j&^^

' ''^H^K $$$&' r

-;~-v4^U-^'.-^i^v,X- ii»_ Li .^. -^ 

: ;>::. ;, /Jp|im: -Henry..iyrenriber\ : \ \ \ ' \ ' 

20 40 60 MILES

0 50 100 KILOMETERS

EXPLANATION 

Nondepositional areas

High to moderate relief 

Depositional areas 

Alluvial fan 

Alluvial plain

Coastal plain 

Marine nearshore sand 

Marine offshore mud 

Offshore shallow-marine sand 

Shoreline

Figure 9. Paleogeographic reconstruction during the late Santonian Desmoscaphites bassleri faunal zone. Area designated as 

offshore shallow-marine sand also contains offshore mud. Southern areal extent of offshore shallow-marine sand deposition 

uncertain.

unconformity that encompasses the late Turanian and the 

lower and middle Coniacian (Peterson and others, 1980). 

Assuming that this area may have been subaerially exposed 

during the time represented by this hiatus (Fred Peterson, 

written commun., 1989), the shoreline south of Salina is 

shown swinging to the southeast. Although the area west of 

the southeast-trending part of the shoreline is shown as an 

area of deposition in figure 8, it is likely that this area was 

a sediment bypass surface where no aggradation occurred or 

that it was actually an area of erosion.

Late Santonian

Desmoscaphites bassleri Faunal Zone

The late Santonian marine shoreline gradually prograded eastward to the west-central part of the study area 

(fig. 9). Coal-bearing strata associated with this shoreline 

have been penetrated in drill holes on the Wasatch Plateau. 

Rocks of this zone are exposed on the plateau's western 

margin. Interpretations of the ages of these rocks are based

Q12 Evolution of Sedimentary Basins Uinta and Piceance Basins
on palynomorph identifications that are sparse and not 

sufficiently detailed to permit precise correlation with 

marine units exposed in eastern Utah and western Colorado.

Sandy strata of the late Santonian Desmoscaphites 

bassleri faunal zone in central and eastern Utah include the 

upper parts of the middle to upper Santonian Emery 

Sandstone Member of the Mancos Shale and their finer 

grained temporal equivalents (Fouch and others, 1983). 

Discontinuous sandstone bodies in this zone that are 

exposed in northeastern and eastern Utah, and less 

commonly in the western Piceance basin in northwestern 

Colorado, have been mapped with the Emery (Cullins, 

1968; Russon, 1987; Clark, 1928). Their buried counterparts are grouped commonly with the Mancos B, an 

informal stratigraphic unit of subsurface usage (Fouch and 

Cashion, 1979; Kellogg, 1977; Cole, 1987) whose age, 

lithologic composition, stratigraphic contacts, and extent are 

not defined. In the study area, the Mancos B probably 

contains strata of early Campanian and Santonian age, 

including some rocks that are temporally equivalent to the 

uppermost part of the Emery Sandstone Member of the 

Mancos Shale exposed east of the Wasatch Plateau. 

Uppermost Santonian rocks in the western part of the study 

area most likely include middle and possibly some lower 

parts of the Sixmile Canyon Formation of the Indianola 

Group (Fouch and others, 1983) and possibly some beds 

mapped with the Blackhawk Formation in this same area 

(Witkind and others, 1987). Equivalents in the northern area 

would be part of the Echo Canyon Conglomerate; in the 

southern area they would be part of the John Henry Member 

of the Straight Cliffs Formation (Peterson and others, 1980; 

Smith, 1983).

Strata of this age contain an extensive erosion surface 

that extends from central Utah to northwestern Colorado. 

This age corresponds to a proposed eustatic sea-level drop 

at 85 Ma (Haq and others, 1987) that may have exposed 

much of the marine shelf. Sandstone bodies formed on this 

erosion surface by both bed-load and storm-generated 

suspension processes (Swift and others, 1987). Ammonites 

from the Desmoscaphites bassleri faunal zone occur in 

strata above and below this erosion surface. Such ammonites have been recovered from the sandy units near 

Woodside, Utah (sec. 10, T. 18 S., R. 14 E.) and from 

oolitic, coarse-grained, sandstone bodies near Floy Canyon, 

about 25 km east of the Green River (W.A. Cobban, written 

commun., 1988). The sandy units that encompass the 

marine scour at Woodside have been included by some 

workers (Newman, 1985; Swift and others, 1987) in the 

early Campanian Kenilworth Member of the Blackhawk 

Formation. Ammonites recovered from both above and 

below the scour are of the late Santonian Desmoscaphites 

bassleri faunal zone (W.A. Cobban, written commun., 

1988). These fossils confirm that the sandy beds are 

temporal equivalents and lithic extensions of the uppermost

part of the Emery Sandstone Member (as shown in Fouch 

and others, 1983, their fig. 4) that is exposed east of the 

Wasatch Plateau and near the northwestern Book Cliffs 

(Clark, 1928; Cobban, 1976; Fouch and others, 1983; 

Russon, 1987).

Early Campanian

Scaphites hippocrepis I Faunal Zone

A transgression in latest Santonian and earliest 

Campanian time caused another landward shift of the 

shoreline into the western part of the study area. Figure 10, 

a reconstruction of the Scaphites hippocrepis I faunal zone 

during earliest Campanian time, illustrates the initial stage 

of gradual shoreline regressions that eventually resulted in 

the withdrawal of the seaway from most of the Utah part of 

the study area by late Campanian time. This systematic 

regression may be a response to either slowing of basin 

subsidence along the western margin of the Cretaceous sea 

in Utah or an increase in clastic sediment supply from the 

west.

The best dated unit in the region is the Panther 

Tongue, the lowest member of the Star Point Sandstone in 

the westernmost Book Cliffs and northeasternmost Wasatch 

Plateau. Younger members of the Star Point have yielded 

fossils whose interpreted ages are not precise enough to 

assign them to a marine molluscan faunal zone. However, 

Fouch and others (1983) assigned the Panther to the 

Scaphites hippocrepis I faunal zone based on marine ostracodes that are interpreted to correspond to this zone.

Recovery of age-diagnostic ammonites and palynomorphs from upper Campanian rocks in the map area is rare. 

As a result, the association of stratigraphic units in the area 

is based on comparisons to the dated Star Point. No 

diagnostic marine fossils have been identified from the 

Muley Canyon Sandstone Member of the Mancos Shale of 

Smith (1983) in the Henry basin, but Peterson and others 

(1980), and Smith (1983) have suggested that the Muley 

Canyon may be the homotaxial equivalent to the Star Point 

of the northern Wasatch Plateau and western Book Cliffs. 

However, its assignment to the Scaphites hippocrepis I 

faunal zone is less certain. In the eastern part of the map 

area, some beds commonly grouped with the Mancos B are 

likely to be of the S. hippocrepis I faunal zone.

An unconformity probably related to local tectonism 

and corresponding to much of the Campanian is present in 

nonmarine rocks adjacent to the thrust belt in southwesternmost Wyoming and north-centralmost Utah (Jacobson and 

Nichols, 1982). The Echo Canyon Conglomerate contains 

palynomorph assemblages of Coniacian to Santonian age, 

and the overlying Hams Fork Conglomerate Member of the 

Evanston Formation contains palynomorphs of late Campanian to early Maastrichtian age. This hiatus would correspond approximately to the zones of Scaphites hippocrepis 

I through Baculites scotti (fig. 3).

Paleogeographic Reconstructions, Colorado and Utah Q13
113° 112'

40

A

A 

A

A A

. _-3R^.'-'-:ix-* . : jiip^pw* I'/fer- ""

\9g&^i$Z&:&m L§-:-y.::-&& \ /./&? ::: = :: Menr 

!§-: -:v»-»?':.;- / : :' .:' Manet

-®-: -Vvty : : : : : : Member of 

X '/,:' ' . ': Mancos Shale f

- ;±=Kart)Z=

0 50 100 KILOMETERS

EXPLANATION 

Nondepositional areas

High to moderate relief 

Depositional areas 

Alluvial fan

Coastal plain 

Marine nearshore sand 

Marine offshore mud 

Shoreline

Figure 10. Paleogeographic reconstruction during the early Campanian Scaphites hippocrepis I faunal zone.

Late Eariy Campanian 

Baculities me/earn/ Faunal Zone

During the late early Campanian, continental facies 

extended from the western and central Utah highlands east 

to the marine shoreline, a distance that generally exceeds 

100 km (fig. 11). Prior to the late early Campanian, the 

alluvial and coastal plain ranged from 40 to 60 km in width 

in central Utah. The widening of the band of nonmarine 

strata of this zone perhaps signals both a decrease in the rate 

in basin subsidence in central Utah and the eventual 

withdrawal of the seaway from the Utah part of the 

Cretaceous landscape. Coarse-grained beds of central Utah

are a part of the undifferentiated Indianola Group and the 

Sixmile Canyon Formation of the Indianola Group. These 

latter units in turn grade into the Kenilworth Member of the 

Blackhawk Formation east of the Wasatch Plateau and in 

the western Book Cliffs, and into the Mancos Shale of 

eastern Utah and Colorado (Fouch and others, 1983). In the 

southern part of the area, western nonmarine sedimentary 

facies are generally assigned to the Wahweap Formation, 

most of which grades eastward into the nonmarine Masuk 

Formation (Eaton, 1990) in the Henry Mountains region. 

Near the thrust belt in the northernmost part of the map 

area, rocks of this age are not preserved. The reconstruction shows this to be a depositional area because

Q14 Evolution of Sedimentary Basins Uinta and Piceance Basins
jiftjafriita j; j: i^^^gEgS

0 20 40 60 MILES

0 50 100 KILOMETERS

EXPLANATION 

Nondepositional areas

High to moderate reliief ^£&v£ Alluvial plain

 _______ ^

Depositional areas . Coastal plain 

Alluvial fan Marine nearshore sand 

Marine offshore mud 

Shoreline

Figure 11. Paleogeographic reconstruction during the late early Campanian Baculites me/earn; faunal zone. The Rock Springs 

Formation contains pollen assemblages that are equivalent to the Baculites obtusus faunal zone; therefore, this unit may or may 

not contain equivalents of the B. me/earn/zone (D.J. Nichols, oral commun., 1989).

post depositional stripping probably accounts for the 

absence of these rocks.

Early Late Campanian

Baculites asperiformis Faunal Zone

For the regressive phase that began in the early 

Campanian, the sea reached its easternmost position during 

the early late Campanian (fig. 12). The shoreline trend in

northwestern Colorado and southern Wyoming is based on 

Zapp and Cobban (1960), Gill and Cobban (1973), Gill and 

Hail (1975), and Johnson (1989). In southeastern Utah, the 

shoreline was east of the Henry Mountains (Peterson and 

others, 1980). The shoreline through southeastern Utah is 

located so that it connects with the shoreline shown for this 

time interval in the San Juan Basin of northwestern New 

Mexico (Molenaar, 1983). The location of the alluvial 

plain-coastal plain boundary is based on Van de Graaff 

(1972) and Gill and Hail (1975).

Paleogeographic Reconstructions, Colorado and Utah Q15
-""V"""1 -^^ : x : -o'4

I Salt Lake

fi\\\\\\\\\\\:\\\\$i$&

, . i'^v.^v ;;« /. > ;:';* : 

-/.v-.-vV;; ';V.:\Wahyyeap-: '

0 20 40 60 MILES

0 50 100 KILOMETERS

EXPLANATION

Nondepositional areas

Alluvial plain 

Coastal plain 

Marine nearshore sand 

Marine offshore mud

High to moderate relief 

Moderate to low relief 

Depositional areas 

Alluvial fan

Shoreline

Figure 12. Paleogeographic reconstruction during the early late Campanian Baculites asperiformis faunal zone.

This latest phase of regression was accompanied by 

an influx of coarse sediment from the Sevier thrust belt. 

Regionally extensive, sheetlike strata deposited on the 

alluvial plain are easily correlated. However, correlation of 

the alluvial-plain and alluvial-fan rocks is less certain 

because these rocks cannot be physically traced into each 

other, outcrops of the alluvial-fan facies are rare, ages of 

these nonmarine rocks are not tightly constrained, and 

eastward-propagating thrusting and accompanying deformation may have resulted in extensive erosion of the 

alluvial-fan deposits. In central Utah, Van de Graaff (1972)

correlated the alluvial-plain facies of the Castlegate Sandstone to the conglomerates at Red Narrows (T. 9 S., Rs. 4 

and 5 E., USM), but Fouch and others (1976) and Ryder and 

others (1976) included these conglomerates in the North 

Horn Formation and interpreted them as basin-margin 

deposits in the younger intermontane basin system. Only on 

the basis of mineralogy are the upper part of the Sixmile 

Canyon Formation (Lawton, 1986) and the conglomerates 

at Bennion Creek (sec. 14, T. 11 S., R. 6 E.) (Ryder and 

others, 1976) correlated to the Castlegate Sandstone.

Q16 Evolution of Sedimentary Basins Uinta and Piceance Basins
113° 112° 111° 110° 109° 108° 107°

A .o:: 0: >.::£&$#

0 20 40 60 MILES

0 50 100 KILOMETERS

E;XPLANATION

Nondepositional areas

High to moderate relief

Moderate to low relief 

Depositional areas

Alluvial fan

Alluvial plain

Coastal plain 

Marine nearshore sand 

Marine offshore mud 

Offshore shallow-marine sand 

Shoreline

Figure 13. Paleogeographic reconstruction at maximum transgression during the middle late Campanian Baculites perplexus 

faunal zone. This faunal zone is absent in the Ericson Formation due to a hiatus (D.J. Nichols, oral commun., 1989).

Middle Late Campanian 

Baculites perplexus Faunal Zone

The transgression that followed the early through 

early late Campanian regression reached its maximum 

landward position, not far west of its preceding maximum 

regressive position, in middle late Campanian time (fig. 13). 

The shoreline trends in the northern part of the map area are

based on Gill and Hail (1975) and are extended to connect 

with the shoreline trend in southern Wyoming at this time, 

shown by Gill and Cobban (1973). In the Green River area, 

the shoreline and coastal-plain boundaries are based on 

Fisher and others (1960) and Pfaff (1985). South of the town 

of Green River, the shoreline swings to the southeast to 

connect with the shoreline during this transgressive phase in 

northwestern New Mexico (Molenaar, 1983). As with the

Paleogeographic Reconstructions, Colorado and Utah Q17
113° 112° 111 °° _____109°__________ 108°

ls6'n\SahcfstoreVc»&&&is> 

r<iirinfir.TiartV/-/v^VOMlNG

107°

^_ /jsHanrs Fork 

\^ _ < % v : Mei

\ .' i_/A l EvanStOn i umiciiiyii :-

\ o V'-o <P (part)^ P'g&$^

,, Salt Lake .>.^° # ^ \ - ?[ ^^i 

j /^lty ^ .^^.0° :^X.

(~ ^j" & -Currant Creek v'r -":'-:v:.;: 

"Xx- /\''/ .- - .

5 A -:l(?

. A &

:3lf^B^;S@fi 

.:&i:^:«?;t^^^i

___^"* T'vl.*. ; ..; ? .;, "**»;* *.;. *.' »,*.- **-* !»V'. -,*.*f .' Ti'icr* T^ ' ""/' 

-^*"" "^5x *'*»*.l* *.";' *? * *?> ', -I-'." ';.*;* t'>. ' J, **' uoi H? . ,' 

A$ ^^®^^fe^'^^

$&' :^^%^:-:V:V-:;.}J^.::^^ ^

' »r - /^:-.:^-;.^^>^^-^^.^^:^-:^,4^:^-^ Jf.-.-r*i.

0 20 40 60 MILES

I I 

0 50 100 KILOMETERS

EXPLANATION

Nondepositional areas

High to moderate relief 

Moderate to low relief 

Depositional areas 

Alluvial fan 

Alluvial plain

Coastal plain 

Marine nearshore sand 

Marine offshore mud 

Shoreline

Figure 14. Paleogeographic reconstruction during the late late Campanian Exiteloceras jenneyi faunal zone during the 

transgression that preceded deposition of the Rollins Sandstone Member and equivalents. Small intermontane (piggy-back) basins 

near eastern margin of highlands are shown containing only alluvial-plain facies, but alluvial-fan and wetland facies also exist.

alluvial facies of the Baculites asperiformis zone, the 

correlatives and boundary between the alluvial-fan and 

alluvial-plain deposits during the B. perplexus zone are 

uncertain.

Late Late Campanian 

Exiteloceras jenneyi Faunal Zone

Following the middle late Campanian transgression, 

the sea's eastward regression during the remainder of the 

Cretaceous was punctuated by minor transgressions. The

reconstruction in figure 14 shows the paleogeography 

during the minor transgression that preceded deposition of 

the Rollins Sandstone Member of the Mount Garfield 

Formation and equivalents. The position of the shoreline is 

the landward limit of marine deposits associated with the 

Rollins Sandstone Member (Johnson, 1989). The landward 

limit of the Cameo coal zone delineated by Johnson (1989) 

is used as the boundary between the coastal and alluvial 

plain.

The paleogeography along the eastern margin of the 

Sevier thrust belt changed significantly from the previous

Q18 Evolution of Sedimentary Basins Uinta and Piceance Basins
Cretaceous patterns of alluvial fans fringing this margin 

everywhere. Alluvial fans fringing the highlands appear to 

be confined to the northern part of the map area. Here, the 

lower part of the Currant Creek Formation and the Hams 

Fork Conglomerate Member of the Evanston Formation 

have palynomorph assemblages of latest Campanian to 

early Maastrichtian age (Jacobson and Nichols, 1982; 

Nichols and Bryant, 1986; Bryant and Nichols, 1988). The 

geometry of the alluvial-fan area is speculative. Locally, 

only the lower 100 m of the Currant Creek has yielded 

age-diagnostic pollen, so both the position of the 

Cretaceous-Tertiary boundary within this unit and the 

lateral extent of the Cretaceous part of this unit are 

unknown. Isby and Picard (1983) interpreted the lower part 

of the Currant Creek to have formed during thrusting in the 

Sevier thrust belt and the upper part to have formed later 

during uplift of the Uinta Mountains.

In the Wasatch Plateau and the Utah Book Cliffs 

areas (fig. 1) occurs a change in paleocurrent directions 

from easterly in early late Campanian time to northeasterly 

and northerly in late late Campanian time. A change from 

dominantly quartzose to more feldspathic mineralogy 

accompanies the paleocurrent change and indicates that the 

sediment source area had changed from the thrust belt on 

the west to areas farther southwest that may or may not have 

been part of the thrust belt (Lawton, 1986; Franczyk and 

others, 1990). The Canaan Peak Formation, which crops out 

in the southwestern part of the map area, contains palynomorphs of late Campanian age in the lower part (Bowers, 

1972), is mineralogically similar to the Price River, Fairer, 

and Tuscher Formations farther to the north, and shows 

similar paleocurrent directions to these units (P.M. Goldstrand, written commun., 1990).

In the southwestern part of the Wasatch Plateau, 

deposits of the alluvial-plain facies onlap a structural high 

(Stanley and Collinson, 1979). Farther west, on the Gunnison Plateau, there are Upper Cretaceous and Paleocene 

rocks that have been correlated to rocks east of this 

structural high. But based on depositional facies relations 

and paleocurrent trends, Lawton (1989; written commun., 

1989) has interpreted this Gunnison Plateau sequence to 

have been deposited in small intermontane basins (piggyback basins) that formed on the thrust allochthon possibly as 

early as latest Campanian time but definitely by Maastrichtian time. The number, dimensions, and distribution of these 

intermontane basins that formed on the allochthon have not 

been completely defined; thus, they are illustrated schematically on the reconstructions.

The entire area east of the south half of the thrust belt 

is shown as an alluvial plain. However, palynomorph 

samples collected 3 m below the top of the Cretaceous 

section along the Book Cliffs east of the Green River belong 

to the lower part of the Aquilapollenites quadrilobus Interval Zone of Nichols and others (1982) and are no younger 

than middle late Campanian (Franczyk and others, 1990).

These samples were collected from 400 m and more above 

rocks that contain fauna from the middle late Campanian 

Baculites perplexus faunal zone, which indicates that 

deposition continued after the time of B. perplexus. During 

Exiteloceras jenneyi faunal zone time in the southern part of 

the alluvial-plain area, sediments were deposited and subsequently eroded, or else this area was a bypass surface on 

which rivers flowed but did not aggrade.

Early Maastrichtian

Baculites reesidei Faunal Zone

During the early Maastrichtian, the seaway remained 

east of the study area during all but two brief periods. The 

first incursion occurred in Baculites reesidei faunal zone 

time when the Twentymile Sandstone Member of the 

Williams Fork Formation formed (fig. 15). The second 

incursion occurred in Baculites clinolobatus faunal zone 

time when the Lion Canyon Sandstone Member of the 

Williams Fork Formation formed (fig. 16). Figure 15 shows 

the shoreline at the western limit of the marginal marine 

Twentymile Sandstone Member. The western limit of the 

coal group overlying the Twentymile Sandstone Member 

variously named the upper coal group of the Williams Fork 

Formation (Fenneman and Gale, 1906), the Paonia Shale 

Member of the Mesaverde Formation (Lee, 1909), or the 

Paonia Shale Member of the Williams Fork Formation of 

the Mesaverde Group (Collins, 1976) defines the landward limit of the coastal plain.

An alluvial-fan complex is shown fringing the highlands in the northwestern part of the map area because of the 

latest Campanian to early Maastrichtian age inferred from 

palynomorph assemblages obtained from the lower part of 

the Currant Creek and the Hams Fork. D.J. Nichols (in 

Franczyk and others, 1990) interpreted a palynomorph 

assemblage obtained from a core of uppermost Cretaceous 

rocks in the eastern Uinta basin to be of early Maastrichtian 

age. Therefore, an alluvial plain is shown east of the 

alluvial-fan area. However, no palynomorph assemblages 

this young were recovered from the uppermost part of the 

Cretaceous along the Book Cliffs (Franczyk and others, 

1990) because of either postdepositional erosion or nondeposition. The latter interpretation is used in the reconstruction because uplift of the San Rafael structure began in 

latest Campanian or early Maastrichtian time (Fouch and 

others, 1983; Lawton, 1986; Franczyk and Nichols, 1988), 

and subsidence may have ceased in the area surrounding the 

uplift. Franczyk and Nichols (1988) interpreted a thin, 

southeasterly-derived conglomerate to conglomeratic sandstone unit that occurs at the base of the North Horn 

Formation in the southern and east-central Wasatch Plateau 

to have formed in the incipient intermontane basin between 

the rising San Rafael uplift and the thrust belt. However, 

palynomorphs have not been recovered from this unit, so an 

early Maastrichtian age is speculative.

Paleogeographic Reconstructions, Colorado and Utah Q19
. ,.,.--o 

_ Mocth Horn

Formation ?: '<< > 

(part)

o

;.' '£$? O SatinaV;;T.

0' o /-^Canaan Peak 

, o q ;Q Formation 

i .0! :Q id 6 :£ :0. (part)

0 20 40 60 MILES

0 50 100 KILOMETERS

EXPLANATION 

Nondepositional areas

High to moderate relief 

Moderate to low relief 

Low relief to nonsubsiding 

Depositional areas 

Alluvial fan

Alluvial plain 

Coastal plain 

Marine nearshore sand 

Marine offshore mud 

Shoreline

Figure 15. Paleogeographic reconstruction during the early Maastrichtian Baculites reesidei faunal zone. Shoreline is shown at 

most landward extent of transgression that preceded deposition of the Twentymile Sandstone Member and equivalents. Areas 

shown as low-relief to nonsubsiding probably had rivers flowing across them and had local wetlands on them.

The Canaan Peak Formation may or may not have 

formed continuously from late Campanian through early 

Paleocene time. No Maastrichtian-age palynomorph assemblages have been recovered from the middle part of this 

unit. The uppermost part of the Canaan Peak is lower 

Paleocene (P.M. Goldstrand, written commun., 1990). In 

this early Maastrichtian reconstruction, a small depositional 

area in the southwestern part of the map area represents

Canaan Peak deposits. Because of postdepositional erosion, 

the eastern extent of deposition is unknown. The facies 

within the Canaan Peak do not indicate accumulation in a 

closed basin (P.M. Goldstrand, written commun., 1990). If 

the area of aggradation was restricted, rivers flowing 

eastward and northeastward from this area may have flowed 

across a bypass surface.

Q20 Evolution of Sedimentary Basins Uinta and Piceance Basins
V- rv . . D. (|^art)';v:.Xy^^;:^;;

,-* I/ r\ .'1 . _i"J -- -.'. t * «. '

.OX 'R /.'' ... (. .'. .;-.T^*v. " . _TT ) ^- (? o . virrrr^-.'.V:;-::',..?-:^.^ 1

.9. . . 0 / p^-^};J;.^y.;;:V:|':;-.:V;.

 y.~;-l i 'Vr/b «>/x 

tfiam^Fork ' \P <bX~ - -. ±i-_ i \ £>* &/ 

F

oaan Peak. __ _ __ _ 

ormation 

(part)

0 20 40 60 MILES

0 50 100 KILOMETERS

EXPLANATION 

Nondepositional areas

High to moderate relief 

Moderate to low relief 

Low relief to nonsubsiding 

Depositional areas 

Alluvial fan

Alluvial plain 

Coastal plain 

Marine nearshore sand 

Marine offshore mud 

Shoreline

Figure 16. Paleogeographic reconstruction during the middle Maastrichtian Baculites clinolobatus faunal zone. Position of 

shoreline through most of the study area is from Gill and Cobban (1969). Alluvial section shown landward of coastal plain is 

identical to that shown for the Baculites rees/c/e/faunal zone reconstruction because the age resolution using palynomorphs is not 

great enough to distinguish the difference in time that these two faunal zones represent.

Middle Maastrichtian

Baculites clinolobatus Faunal Zone

The shoreline trend shifted from predominantly 

northeasterly to northwesterly during the second Maastrichtian incursion of the sea into the study area (fig. 16). The 

presence of the mollusk-bearing, marginal-marine Lion 

Canyon Sandstone Member of the Williams Fork Formation 

and the coal zone in the Williams Fork that formed

landward of the Lion Canyon shoreline establish the 

position of the shoreline and coastal plain area. However, of 

the nonmarine strata deposited contemporaneously with this 

incursion, much has been eroded; additionally, palynology 

used to date the nonmarine strata cannot distinguish 

subdivisions finer than early and late Maastrichtian. 

Therefore, the distribution of the nonmarine paleogeography is uncertain and is shown as the same as for the 

early Maastrichtian.

Paleogeographic Reconstructions, Colorado and Utah Q21
113° 112'

0 20 40 60 MILES

0 50 100 KILOMETERS

EXPLANATION

Nondepositional areas

Moderate to low relief 

Low relief to nonsubsiding

 0-

Depositional areas 

Alluvial fan 

Alluvial plain 

Wetlands 

Lacustrine

Figure 17 Paleogeographic reconstruction during the late Maastrichtian. Existence of mixed alluvial plain and wetland area in 

southwestern map area is speculative. Mixed alluvial-fan, alluvial-plain, wetland, and shallow-lacustrine environments existed 

over much of the depositional areas.

Late Maastrichtian

From late Maastrichtian time on, the sea had regressed completely from the map area (fig. 17), and the time 

intervals can no longer be correlated to marine faunal zones. 

No published accounts mentioning late Maastrichtian-age 

palynomorph assemblages from the study area exist. J. 

Zawiskie (oral commun., 1987) reported late Maastrichtianage palynomorphs both from the Gunnison Plateau and 

from the lower part of the North Horn Formation at the type 

locality on the Wasatch Plateau. Dinosaur bones also occur 

in the lower part of the North Horn at the type locality

(Spieker, 1946). A Maastrichtian charophyte assemblage 

recovered from the base of the North Horn Formation at 

Price Canyon (sec. 21, T. 12 S., R. 9 E.; Fouch and others, 

1987) is similar to global late Maastrichtian-age charophyte 

assemblages, which suggests a late Maastrichtian age for 

this assemblage in Price Canyon (R.M. Forester, oral 

commun., 1989). Based on magnetostratigraphy, Hobbs 

(1989) inferred latest Maastrichtian deposition on the 

Gunnison Plateau. These data indicate that late Maastrichtian deposition was restricted to the intermontane basins on 

the allochthon and west of the San Rafael uplift. Bryant and 

Nichols (1988) showed the initiation of the main phase of

Q22 Evolution of Sedimentary Basins Uinta and Piceance Basins
movement in the western part of the Uinta uplift to have 

begun in late Maastrichtian time. The Sawatch uplift in 

Colorado also became active at this time (Obradovich and 

others, 1969; Tweto, 1975). Except for the restricted basins 

and the active uplifts, most of the map area had slight or no 

relief and was not subsiding.

Middle Paleocene

The early Paleocene paleogeography probably did not 

vary greatly from that in the late Maastrichtian. The only 

published record of early Paleocene-age palynomorphs is 

from a thin, areally restricted conglomerate and conglomerate sandstone unit, the Dark Canyon sequence of the 

Wasatch Formation, in the eastern Book Cliffs (Franczyk 

and others, 1990). Scattered lags of conglomerate that occur 

locally throughout the map area may have formed adjacent 

to uplifts in the early or middle Paleocene but do not 

indicate the initiation of subsidence. Although only early 

and late subdivisions of the Paleocene are formally 

recognized, Nichols and Ott (1978) proposed early, middle, 

and late subdivisions for the Paleocene based on palynomorph assemblages. Our use of middle Paleocene follows 

that of Nichols and Ott (1978).

In middle Paleocene time, the Uinta and Piceance 

basins began to acquire their present-day configuration (fig. 

18). In the Uinta basin, the primary source of clastic 

material, based on the occurrence and distribution of conglomerate both in the Currant Creek Formation and in the 

North Horn Formation at the Red Narrows (T. 9 S., Rs. 4 

and 5 E., USM) and Diamond Fork (Tps. 4 and 5 S., Rs. 4 

and 5 E., USM) areas, was from the northwest and west 

margins of the basin. Palynomorphs have not been 

recovered from the Diamond Fork and Red Narrows outcrops. The upper part of these units intertongues with 

Paleocene limestone beds (Fouch and others, 1976), but no 

evidence exists for the age of the lower part.

In the lower part of the North Horn in Price Canyon 

northwest of Price, Utah, a thick fluvial sandstone sequence 

has a sharp, probably unconformable contact with the 

underlying late Maastrichtian part of the North Horn. This 

sandstone sequence may be the alluvial-plain equivalent of 

these conglomerates. Middle Paleocene-age palynomorphs 

were collected from the uppermost part of this sandstone 

sequence (Fouch and others, 1987), and paleocurrent trends 

indicate a source to the west and northwest (Franczyk and 

others, 1989). However, western parts of this alluvial-plain 

system have not been identified. Well logs from the 

west-central part of the Uinta basin (Carter Oil Co., 

J. Burnett #1, sec. 34, T. 4 S., R. 11 W., USM; Shell Oil Co., 

Ute Tribal #1-16D, sec. 16, T. 4 S., R. 9 W., USM) do 

not show a thick fluvial section in the lower part of the 

middle Paleocene section. The southwestern part of the 

Uinta basin contains no well-exposed, continuous, unfaulted 

outcrops of the Cretaceous through the late Paleocene

section. Therefore, the geometry and distribution of the 

alluvial-plain facies in the lower part of the North Horn in 

Price Canyon are unknown. Possibly this alluvial-plain 

facies existed in early middle Paleocene time and was 

confined to the southwesternmost part of the Uinta basin. 

The reconstruction in figure 18 shows the alluvial environments confined to the north and west edges of the Uinta 

basin and the mixed wetland and lacustrine environments 

throughout most of the basin interior, a distribution that 

probably existed during most of the middle Paleocene.

Along the Book Cliffs north of the San Rafael uplift, 

rocks containing middle Paleocene palynomorphs overlie 

Campanian rocks; and slightly farther east, in the Green 

River area, upper Paleocene rocks overlie Campanian or, 

locally, lower Paleocene rocks. In the subsurface of the 

Uinta basin, Fouch and Cashion (1979) showed the North 

Horn thinning to the east. Although the easternmost limit of 

middle Paleocene rocks is not known, the edge of middle 

Paleocene deposition is shown to be immediately west of 

the Green River. Within the map area of this report, the 

southern limits of middle Paleocene deposition are also 

speculative. Palynomorphs collected from the base of the 

Pine Hollow Formation, which unconformably overlies the 

Canaan Peak Formation, indicate these rocks to be lower 

Paleocene (P.M. Goldstrand, written commun., 1990). 

Goldstrand (1989) interpreted the Pine Hollow and overlying Claron Formation to have formed in an internally 

drained basin.

In the Piceance basin, onlapping of the CretaceousTertiary unconformity appears to have begun in middle 

Paleocene time when a coarse-grained fluvial system spread 

westward from the trough of the basin. Middle Paleocene 

palynomorphs have been collected from the lower part of 

the Paleocene section along both the Grand Hogback, near 

the structural trough of the basin (Newman, 1974), and the 

White River in the northern part of the basin (Hail, 1973). 

Along the western margin of the Piceance basin, the 

unconformity was not onlapped until near the beginning of 

the late Paleocene (Johnson and May, 1978, 1980). Coarse 

pebbles and cobbles, at least partly derived from the 

Sawatch uplift southeast of the basin (Tweto, 1975), occur 

throughout much of the middle Paleocene section.

Early Late Paleocene

In early late Paleocene time in the Uinta basin of 

northeastern Utah, the area of shallow lakes separated by 

wetlands expanded; its eastern extent was within a few 

miles of the crest of the Douglas Creek arch (fig. 19). The 

deposits formed in these environments compose the 

Flagstaff Member of the Green River Formation (Fouch, 

1976) in the Uinta basin. A deeper, more extensive lake may 

have begun to form at this time along the depositional axis

Paieogeographic Reconstructions, Colorado and Utah Q23
113° 112° 111

t Lake rv. /Y. A/\ r~/-^ /\ i

j^ XluHajft Creek /\ i

/A ^ . ** .-'< . i

r North^torn^g^ 

(part) ~

0 20 40 60 MILES

I II I

I I

0 50 100 KILOMETERS

EXPLANATION

Nondepositional areas Depositional areas

 O .o. *o

Alluvial fan

Alluvial plain

Wetlands

Lacustrine

High to moderate relief 

Moderate to low relief 

Low relief to nonsubsiding

\v

Figure 18. Paleogeographic reconstruction during the middle Paleocene. Small patches of alluvial-fan facies symbols in 

westernmost Colorado indicate scattered conglomeratic lags.

of the Uinta basin, close to the south flank of the Uinta 

Mountains. Areas on the northwest flank of the Uinta 

Mountains where thrusting had been active in latest 

Cretaceous and Paleocene time began to subside and accumulate sediment. Abundant detritus was shed from the south 

flank of the Uinta Mountains into a narrow zone along the 

northern part of the Uinta basin. However, clastic influx to 

the southern part of the Uinta basin was low.

Stanley and Collinson (1979) documented the following environmental differences across the Wasatch Plateau in 

late Paleocene time. In the more rapidly subsiding western 

part of the Wasatch Plateau, lacustrine and wetland environments were dominant, and the lower member of the

Flagstaff Limestone formed. Contemporaneously in the 

eastern, less rapidly subsiding part of the Wasatch Plateau 

near the west flank of the San Rafael uplift, floodplains 

were dominant, and the upper part of the North Horn 

Formation formed. Wells (1983) also provided a detailed 

description of the rock types and the inferred depositional 

environments for the entire Flagstaff Limestone in the 

Wasatch Plateau area.

Palynomorphs recovered from the basal part of the 

Claron Formation southwest of the map area indicate a late 

Paleocene age (P.M. Goldstrand, written commun., 1990). 

Therefore, this unit is shown forming in the southwestern 

part of the map area at this time.

Q24 Evolution of Sedimentary Basins Uinta and Piceance Basins
113° 112° 111° 110° 109° 108° 107°

^feartr i w -w

 ' :^fff; \i/ I Flagstaff

-JnfWv Member cof i 

i Green River 

T_ J Formation

0 20 40 60 MILES

0 50 100 KILOMETERS

EXPLANATION 

Nondepositional areas Depositional areas

High to moderate relief 

Moderate to low relief 

Low relief to nonsubsidiing M/ 

M/

Alluvial fan 

Alluvial plain 

Wetlands 

Lacustrine

Figure 19. Paleogeographic reconstruction during the early late Paleocene. Flagstaff Member is a member ot the Green River 

Formation.

Wetland and lacustrine environments also expanded 

and covered much of the Piceance basin during the late 

Paleocene. The resulting deposits overlie middle to possibly 

late Paleocene fluvial deposits in the eastern and central 

areas of the basin and, in the western part of the basin, 

directly overlie older Paleocene conglomeratic lag deposits, 

which formed on the Cretaceous-Tertiary unconformity. 

These upper Paleocene wetland and lacustrine deposits 

pinch out by depositional onlap on the Cretaceous-Tertiary 

unconformity a few miles east of the crest of the Douglas 

Creek arch. This depositional pattern indicates that wetland 

and lacustrine systems in the Uinta and Piceance basins 

were not continuous. Upper Paleocene deposits in the

Piceance basin generally contain fewer fossiliferous 

limestones and more gray shale, carbonaceous shale, and 

thin coal beds than those in the Uinta basin, which indicates 

differences in water chemistry, hydrology, and abundance 

of clastic material in these basins.

In late late Paleocene time, a major influx of 

feldspathic-rich clastic material into the southern part of the 

Uinta basin began. Alluvial environments, characterized by 

sediment derived from the south and southeast, displaced 

the lacustrine and wetland environments to the north. The 

lower part of the Colton Formation formed in this alluvial 

setting. In the Piceance basin, alluvial environments, 

containing sediment derived from the southwest, southeast,

Paleogeographic Reconstructions, Colorado and Utah Q25
113° 112° 111° 110° 109° 108° 107°

iff^^^&^jm^^-. ^~*^~~7 ^7 I | /\>.T- y\ * ^-^ ^~- Formation- rui 11 laiiuii _. __ . ; ;- . . - f:.: *.*,vt ::T;.W9satch " vyoaiv/t i x > > .. . :.". « ' ;.

- "H<\ '. t~:^v ^ ^ ^- ".i;X':--.:-i:(Formfltion. /^ ,.;/-':. :>::'

i_5 ^\ " ' 'iiiil'.S 'VPrairt-'.>":'-r'j';::''-"!: :':"v.-.%.\'-"' /\'.: :'.,' ' : :' ^-<>^-;ti^ii®& ^m

: ^^>,.'^^^^:SifS Afe O -° Colton and Green F^ver-0-

_~ 

Member 

(part)1-^? 

, Colton and Greerj J__ ~ 5^^nA

- ~'**' : '' ''** " ' '"'

0 20 40 60 MILES 

_______I I

0 50 100 KILOMETERS

EXPLANATION 

Nondepositional areas Depositional areas

Alluvial fan 

Alluvial plain 

Wetlands 

Marginal lacustrine

High to moderate relief 

Moderate to low relief 

Low relief to nonsubsiding

\i/

M/

Lacustrine

Figure 20. Paleogeographic reconstruction during the early Eocene. Use of Duchesne River Formation in northwestern part of 

Uinta basin from Bryant and others (1989a).

and possibly north and northeast, displaced the wetland and 

lacustrine environments into the north-central part of the 

basin.

Early Eocene

The major clastic influx into both the Uinta and 

Piceance basins that began in late late Paleocene time 

continued into earliest Eocene time. Subsequently, but still 

in early Eocene time, the lake systems expanded not only in

the Uinta and Piceance basins, but also in the area covered 

by both the Green River and Sand Wash basins in Wyoming 

and northwest Colorado north of the Uinta Mountains (fig. 

20). A single, large lake that had well-defined open- and 

marginal-lacustrine zones occupied each of these basins, in 

contrast to the preceding mixed lacustrine and wetland 

systems.

A somewhat complicated nomenclature has evolved 

for these large lakes. Stokes (1986) used the name Green 

River Lakes to collectively refer to all the large Tertiary 

lakes that existed in this area of Wyoming, Colorado, and

Q26 Evolution of Sedimentary Basins Uinta and Piceance Basins
Utah. Lake Gosiute refers to the lake that occupied the 

Green River and Sand Wash basins. Lake Uinta was first 

applied to a single large lake that extended across both the 

Uinta and Piceance basins (Bradley, 1931). However, this 

single large lake existed only briefly, because during most 

of the early Eocene the low relief area of the Douglas Creek 

arch separated the lake within the Uinta basin from that in 

Piceance basin, and during most of the late Eocene a lake 

existed only in the Uinta basin. Based on the original 

application of the name Lake Uinta, Johnson (1985) 

questioned whether anything but the single lake covering 

both basins should be referred to as Lake Uinta. In our 

discussion, rather than apply different names to the lakes 

that occupied the Uinta and Piceance basins before they 

became connected and when the lake only occupied the 

Uinta basin in the late Eocene, we use Lake Uinta to refer 

to the Eocene lakes that occupied the Uinta and Piceance 

basins.

The early Eocene lake in the Uinta basin has 

frequently been referred to as Lake Flagstaff. (See Spieker, 

1946; Stanley and Collinson, 1979.) However, the early 

Eocene deposits that constitute the upper part of the 

Flagstaff Limestone on the Wasatch Plateau (Spieker, 1946; 

LaRocque, 1960; Stanley and Collinson, 1979; Witkind and 

others, 1987) formed in a southwest extension of the large 

Lake Uinta in the Uinta basin (Bradley, 1930; Cashion, 

1972; Ryder and others, 1976; Fouch, 1976; Picard, 1985). 

Therefore, referring to the early Eocene lake system in the 

Wasatch Plateau and more western areas as the Flagstaff 

arm of Lake Uinta is more appropriate. During this phase of 

lake expansion, the previously isolated depositional basins 

on the allochthon and in the Wasatch Plateau area were 

united. Beds temporally and lithologically similar to the 

upper part of the Flagstaff Limestone extend north of the 

Wasatch Plateau along the east flank of the Wasatch Range 

on the west side of the Uinta basin. Fouch (1976) assigned 

these beds to the Flagstaff Member of the Green River 

Formation because they are also continuous with strata in 

the Green River Formation along the Uinta basin axis of 

deposition south of the Uinta Mountains.

The Flagstaff arm may have extended south of the 

Wasatch Plateau into southwestern Utah and joined what 

Stokes (1986) called Lake Claron. Mullet (1989) interpreted 

the Tertiary Claron Formation to have formed in a slowly 

subsiding area within shallow, localized lake and floodplain 

environments; long periods of subaerial exposure over 

extensive areas were common. The age of this formation is 

not well documented because of the rarity and poor 

preservation of fossils and the lack of radiometrically 

datable tuff beds. It is possible that the shallow lakes, 

wetlands, and floodplains of the Claron depositional system 

were separated from the Flagstaff arm of Lake Uinta by a 

nonsubsiding area presently covered by Tertiary volcanic 

rocks.

In Utah, the most rapid subsidence and thickest 

accumulation of sediments occurred south of the Uinta 

Mountains along the northern axis of the rapidly subsiding 

Uinta basin. In this area, alluvial fans, composed of thick 

gravel and coarse sand sequences, were shed south from the 

mountain front toward the edge of Lake Uinta. These 

deposits form part of the Colton Formation in the northwest 

and north-central parts of the Uinta basin and indicate high 

relief in the Uinta Mountains. The conglomeratic alluvialfan beds may have extended to the northeastern basin 

margin, but drill holes have not yet penetrated them in this 

part of the basin. These alluvial deposits grade basinward in 

the marginal- and open-lacustrine deposits of the Green 

River Formation.

In the western part of the map area, coarse-grained 

sandstones and conglomerates associated with lake beds are 

only locally preserved. Areas that were previously highlands in the Sevier thrust belt of central Utah were probably 

low relief areas interspersed with local wetlands during the 

early Eocene.

During the early Eocene in Utah, Lake Uinta and the 

Flagstaff arm contained alkaline, but relatively fresh water 

that was low in dissolved chloride. Gypsum precipitated to 

form beds in the open-lacustrine part of the Flagstaff arm 

(Stanley and Collinson, 1979), and gypsum formed in 

shallow-lake and pond settings near the margin of the main 

body of Lake Uinta in the Uinta basin (Ryder and others, 

1976; Fouch and Cashion, 1979; Fouch, 1981). Subsequently, the lake water became more saline, and by the end 

of the early Eocene, waters in the central part of the lake 

were relatively high in dissolved chlorides, and calciumsulfate precipitates were rare.

The Piceance basin experienced a widespread expansion of the lake system in the early Eocene simultaneous 

with the expansion in the Uinta basin. Although a mixed 

lacustrine and wetland system evolved into single large 

lakes in each basin, the lakes were separate, and the 

sediments deposited in and adjacent to the lakes in each 

basin are characterized by notable differences. The center of 

most rapid subsidence and thickest accumulation of sediment in the Piceance basin is on the east side of the basin 

adjacent to the White River uplift. Coarse sediments shed 

from highlands on this uplift form a narrow zone of alluvial 

(Wasatch Formation) and mixed alluvial and marginallacustrine deposits along the east and north edge of the 

basin. These sediments are generally not as coarse as those 

shed from the south flank of the Uinta Mountains, suggesting considerably lower relief on the White River uplift 

than on the Uinta uplift.

In the Piceance basin, the marginal-lacustrine 

deposits are characterized by mollusk- and ostracode-rich 

sandstone and limestone, gray shale, carbonaceous shale, 

and less commonly, thin coal beds. The deeper water, 

open-lacustrine deposits are characterized by widespread,

Paleogeographic Reconstructions, Colorado and Utah Q27
113° 112° 110° 109° 108° 107°

_Wasafcnand I 

Formations

0 20 40 60 MILES 

J____I

0 50 100 KILOMETERS 

EXPLANATION

Nondepositional areas Depositional areas

O^o-o 

High to moderate relief

Moderate to low relief 

Low relief to nonsubsiding

Figure 21 . Paleogeographic reconstruction during the middle Eocene (time 1). Use of Duchesne River Formation in northwestern 

part of Uinta basin from Bryant and others (1989a).

O.Q.0

: P.; o:

:$%&;£

M/

MX

 ~

-^-^

Alluvial fan

Alluvial plain

Wetlands

Marginal lacustrine

Lacustrine

moderately rich, clay-rich oil-shale beds. The lowermost 

Green River Formation rocks formed in the Piceance basin 

at this time were originally included in the lower part of the 

Douglas Creek Member of the Green River Formation by 

Bradley (1931), but Johnson (1984) renamed them the Cow 

Ridge Member of the Green River Formation.

The combination of abundant fresh-water mollusks 

and a lack of evaporite minerals in the marginal-lacustrine 

deposits of the Cow Ridge Member distinguishes these 

rocks from the younger, generally mollusk poor Lake Uinta 

deposits in the Piceance basin. The fossil assemblage and 

mineralogy also indicate that the salinity of the lake waters

during this early Eocene lake phase was low but increased 

gradually through time.

Middle Eocene

Near the end of the early Eocene, the lakes in both the 

Uinta and Piceance basins expanded farther, crossed the 

Douglas Creek arch, and, during the middle Eocene, united 

to form the largest of the Paleogene internally drained 

hydrologic basins (fig. 21). Johnson (1985) referred to the 

initiation of this expansion in the Piceance as the Long Point

Q28 Evolution of Sedimentary Basins Uinta and Piceance Basins
transgression, based on the widespread occurrence of a 

mollusk-rich marker bed he named the Long Point Bed of 

the Douglas Creek Member of the Green River Formation. 

Although Lake Uinta became one large lake, it had two 

distinct lacustrine depocenters: one in the Uinta basin 

slightly south of the axis of maximum subsidence near the 

south flank of the Uinta Mountains, and one in the Piceance 

basin slightly west of the area of maximum subsidence 

along the west flank of the White River uplift.

Abundant sediment continued to be shed from the 

Uinta Mountains. Analysis of drill-hole lithologic logs of 

middle Eocene strata indicate that alluvial fans formed near 

some of the Uinta basin's fault-bounded, high-relief margins and extended from the mountain front into and (or) 

near Lake Uinta. Sequences as much as 1,000 m thick of 

middle and early late(?) Eocene-age lacustrine and fluvial 

rocks are along the subsidence axis of the Uinta basin. Thick 

sequences of clastic and chemically precipitated sediments, 

including the kerogen-rich carbonate mud that became oil 

shale, formed within the lake in both basins.

The formation of halite (NaCl) and (or) nahcolite 

(NaHCO3) evaporite beds and disseminated dawsonite 

[NaAl(OH)2CO3] in conjunction with the demise of the 

mollusk population indicates an increase in lake-water 

salinity and alkalinity due to absence of an outlet. Initially, 

precipitation of evaporite minerals occurred only in the lake 

depocenter in the Piceance basin, suggesting that brines 

were confined to the Piceance depocenter and that there was 

probably a net flow of water from the Uinta basin across the 

shallow lacustrine area around the Douglas Creek arch and 

into the Piceance (Dyni, 1981; Johnson, 1985). Later, 

during the filling of the Piceance basin part of Lake Uinta, 

the area of evaporite deposition shifted westward into the 

Uinta basin part of Lake Uinta.

During the middle Eocene, Lake Uinta expanded 

farther (fig. 22). For a relatively short period of time, during 

deposition of the Mahogany oil-shale bed, the lake reached 

its maximum extent when it may have covered the entire 

Uinta and Piceance sedimentary basins. Its maximum size 

was probably slightly larger than shown in figure 22. The 

extent of the lake along the southern margin of the Uinta 

basin and in the Wasatch Plateau is unknown because of 

removal of Tertiary strata by erosion. Isolated exposures of 

poorly dated lacustrine and fluvial beds in central Utah west 

of the Wasatch Plateau contain tuffaceous debris. These 

beds have been mapped as Green River Formation, based on 

their stratigraphic position and their lithologic similarity to 

Green River strata in the Uinta basin, but precise correlation 

of strata between these two areas remains uncertain. Oil 

shale or tuff of the Mahogany zone has not been identified 

south and west of the westernmost part of the Uinta basin.

The paleogeographic reconstruction for the western 

and southwesternmost part of the map area in figure 22 is 

extremely conjectural. If the Claron depositional system 

was still active, it probably consisted of interspersed wetlands and shallow lakes. A gently sloping, nonsubsiding 

area of alluvial plains and wetlands locally separated by 

scattered, small uplands of moderate to low relief probably 

bounded the west side of Lake Uinta and its associated 

peripheral environments.

Late Eocene

In middle Eocene time, shortly after deposition of the 

Mahogany oil-shale bed, a major influx of volcaniclastic 

sediment originating in western Wyoming came into the 

northern Piceance basin. These volcaniclastics prograded 

from north to south across the Piceance basin and filled the 

northern Piceance part of Lake Uinta. Eventually, these 

sediments spilled over the Douglas Creek arch and filled 

Lake Uinta in the eastern part of the Uinta basin before the 

influx of volcaniclastic debris ended. Accordingly, Lake 

Uinta's depocenter shifted westward to the western and 

southwestern part of the Uinta basin. By late Eocene time, 

Lake Uinta had shrunk to the western and north-central part 

of the Uinta basin (fig. 23). In the western Uinta basin, a 

sequence of lacustrine and marginal lacustrine deposits 

more than 750 m thick occurs above the Mahogany bed. 

Locally, more than 300 m of this sequence is characterized 

by abundant, bedded evaporite minerals (Dyni and others, 

1985), indicating that during the final phase of Lake Uinta 

the lake still lacked an outlet and the waters had become 

more saline as the lake retreated westward. Based on 

isotopic ages of tuff beds in the western Uinta basin, Bryant 

and others (1989a) determined that lacustrine deposition in 

this area continued until the latest Eocene, perhaps to 37.6 

Ma. The source of the tuffaceous material was probably 

volcanic centers in west-central Utah, because these tuff 

beds are younger than the volcanism in Wyoming that 

supplied the older volcaniclastic sediments, and these tuff 

beds thicken to the west (J.R. Dyni, written commun., 

1990). The southern extent of Lake Uinta on the west side 

of the Uinta basin is unknown, as rocks of this age have 

been eroded. The last phase of the lake may have extended 

southward into the Wasatch Plateau and westward into the 

easternmost Great Basin.

Latest Eocene and (or) Earliest Oligocene

During the latest Eocene and (or) earliest Oligocene, 

the large lakes that dominated most of previous Paleogene 

time disappeared from this part of the Western United 

States. Figure 24 illustrates the paleogeography during the 

latest Eocene and (or) early Oligocene when all that 

remained of the former Lake Uinta was scattered wetlands. 

Renewed uplift on the Uinta Mountains during this time 

resulted in an influx of sediments (the Duchesne River

Paleogeographic Reconstructions, Colorado and Utah Q29
113° 112° 111

P£y^£S4!r-s<M^ X ^^^^^^f^^^^^^^^^^^T^^^^^^^-^ '$$$ rT/\" /v "^

^&$J&$&IS&^6ffibW /*5^^m&*,.._- ^~^-^A~-'- $$##: . A\ *£ *-V'" s ^^°^^ -^\^/^r "x^S^^^^^ ^1?^- r\^ ^

Lake \<r^/\° .-'^VVasatchandl ^-< ^_/^J -f-^^^-^r^--^ .:^orjrnation . » ^ 

3EL ^C.v s/ ;. /] Colton Formatibns^ ^^1 A /V^y,..- ~- .£33&$8$).-: :'; . \ '*$ ;

^^^^o^&S&^^f^^ -1 ^11 .1. .0Jo(part) 0 <b.o?o.

?^^

-

 . ; : '.. ' . '. :.-' ";:: .*?;r,: ' ': . ' ' 

^Z^ Anvil Points-' 

_ Mbr (paitt)

, Parachute ~-^pI=. J 

T^- Creek Member \- _ N-- nf r;r*iSTri?l\TS7" Glenwood

Formation I _~~_^ * / .1 I __TTjrand -

 / Green- 

"^ -3 River '

 = - ^ &^_^_>^_ " v'-S.N ' *\ / 

_ / * _ *. »v..-\. \ __

^~~ 

0 20 40 60 MILES

0 50 100 KILOMETERS

EXPLANATION 

Nondepositional areas Depositional areas

High to moderate relief 

Moderate to low relief 

Low relief to nonsubsiding

O.O.Q

:Q:O: ' :' :' ;.:'' " ':

 ' ', :' ','.' '' 

' :' > .' .' " ' ' :' ' '

M/ 

M/

 ~

ti^l

Alluvial fan

Wetlands

Marginal lacustrine

Lacustrine

Figure 22. Paleogeographic reconstruction during the middle Eocene (time 2) during maximum expansion of Lake Uinta as 

represented by the Mahogany oil-shale bed. Boundaries of the lake at Mahogany time may have been slightly greater than shown 

here. Anvil Points is a member of the Green River Formation. Use of Duchesne River Formation in northwestern part of Uinta basin 

from Bryant and others (1989a).

Formation) that filled the northern part of the Uinta basin 

(Andersen and Picard, 1974; Bryant and Nichols, 1988). A 

sediment source west of the Gunnison Plateau provided the 

lithic-rich clastic material in the uppermost lacustrine beds 

and in the overlying alluvial deposits (the Crazy Hollow 

Formation) in central Utah (Weiss, 1982). Concurrent with 

the final uplift of the Uinta Mountains was volcanism in the 

eastern Great Basin area (Lindsey and others, 1975; Fouch,

1979; Witkind and Marvin, 1989; Bryant and others, 

1989b). Locally extensive deposits of volcanic and volcaniclastic detritus mantled much of the western part of the map 

area and filled the remaining topographic lows formerly 

occupied by lakes and wetlands. Parts of the Keetley 

Volcanics and the mixed volcanic and volcaniclastic Goldens Ranch and Moroni Formations, all of which occur 

within the map area, formed at this time.

Q30 Evolution of Sedimentary Basins Uinta and Piceance Basins
113° 112° 110° 109° 108° 107°

0 20 40 60 MILES

0 50 100 KILOMETERS

EXPLANATION 

Nondepositional areas Depositional areas

n ' o ' A '

High to moderate relief 

Moderate to low relief 

Low relief to nonsubsiding

O.P.0.

:9:0: :

i -;t-;;*f"v.v.

M/ 

\l/

 ~

l^Z.

Alluvial fan

Wetlands

Marginal lacustrine

Lacustrine

Figure 23. Paleogeographic reconstruction during the late Eocene. Use of Duchesne River Formation in northwestern part of 

Uinta basin from Bryant and others (1989a).

SUMMARY

Figure 25 summarizes the structural and depositional 

events that occurred in the study area from late early 

Cretaceous to late Oligocene time. Throughout most of the 

Late Cretaceous, Sevier-style tectonism, characterized by 

thin-skinned thrusting, was dominant in the western part of 

the area and resulted in the formation of a marine foreland 

basin. In the latest part of the Cretaceous and throughout 

much of the Paleogene, Laramide-style tectonism, characterized by crystalline basement-involved uplifts, was dominant in the area and resulted in the formation of numerous 

intermontane basins in which large lakes developed. 

Toward the end of this phase of tectonism, volcanic activity 

began in the western part of the area. In each case, the final 

phase of a tectonic event temporally overlaps the initial 

phase of the succeeding tectonic event.

The paleogeography and resulting lithofacies distributions were influenced by the types of basins that 

developed during these different tectonic phases. The sea 

occupied parts of the foreland basin within the study area

Paleogeographic Reconstructions, Colorado and Utah Q31
113'

0 20 40 60 MILES

0 50 100 KILOMETERS

EXPLANATION 

Nondepositional areas Depositional areas

r\. o~. /~i~.

Alluvial fan

Alluvial plain 

Wetlands 

Volcanic area

High to moderate relief 

Moderate to low relief 

Low relief to nonsubsiding \i/

Figure 24. Paleogeographic reconstruction during the latest Eocene and (or) early Oligocene. Areas surrounding the volcanic 

centers were locally sites of ash-flow, alluvial, and shallow lacustrine deposition. Exact distribution of these depositional 

environments is unknown, and this area is shown schematically as consisting of mixed low-relief and wetland areas.

for much of the Late Cretaceous. Nonmarine environments 

paralleled the thrust belt and graded eastward into marine 

environments. Repeated transgressions and regressions of 

the sea resulted in significant changes in shoreline location 

and produced a depositional sequence of complexly intertonguing nonmarine and marine units. The formation of 

intermontane basins resulted in internally drained depositional systems in which shallow lakes and wetlands 

predominated in latest Cretaceous and Paleocene time and 

large lakes predominated in Eocene time. By middle Eocene 

time, one lake, Lake Uinta, covered much of the area.

Alluvial environments generally occurred along the basin 

margins, but their distribution was controlled by the 

proximity of the surrounding uplifts and the subsidence 

pattern of the basin. Lacustrine environments generally 

occurred in the basin interiors, but frequent lake expansions 

and contractions resulted in large variations in lake size and 

wide zones of intertonguing alluvial and lacustrine deposits. 

Saline minerals and oil shale are common within the 

lacustrine deposits. The lake began to decrease in size 

toward the end of the middle Eocene and had disappeared 

by latest Eocene or earliest Oligocene time.

Q32 Evolution of Sedimentary Basins Uinta and Piceance Basins
Ma

30 

40 

50 

60 

70 

80 

90 

100 

AGE

t

CD 

Q.

CC

^"

CC 

LU

^~

<a

(ft 

O

UJ 

O

UJ

cc

o

t

CD 

_O.

LU

Z

LU

PALEOG

LU

<

^

I

_J

oc

UJ

LU

z

o <®

o£

o

EOCENE

LU

Z

LU

O

0

LU

_l

Q_

LATE

EARLY

LATE

MIDDLE

EARLY

LATE

EARLY

MAASTRICHTIAN

CAMPANIAN

SANTONIAN

CONIACIAN

TURONIAN

CENOMANIAN

ALBIAN

(part)

STRUCTURAL

EVENTS

i'^cro| j

E

CO 'E

0

tj

-Laramide t&

j ~i

T ~r~ "

E

CO 'E 

o

o

CD

CD '>

CD

T

0)

to

.c

~

CD

C

c

CO

c

IEhl

j> 

L

3 

3

5

o

c

c

CD

E

CD 

CO

.a

CD

c

"CD

to

O

1

. * -> 6

'& »- CD 3 

°'C'fc tj

CO O <U ^

o-^S ^ cut! co a) 

c o ^ 2 

 E

CD

CD

c

CD 

CD

0)

.a

c

CD 

CO

CD

Q.

o» " c

'wli) s CDCD _g

I« S

^ D -M

C * ^"

EC E

S-M ?

1

1

(

c:

a) 

a. 

c

co

 O

c: aj "53

CJ}

c:

1

 CO CD

13 £ P

E Q JD

W j ;

i

DEPOSITIONAL

EVENTS

CO

"5.

c ow

CD_C CD Ts'^aS

CD C C

E^E Eoo

Q£L<¥

4= C

co.So

C CO 0 

f. CD C

£3^3 ^

111 '^ CO C

co c w 

do 03 

Q.ii^3 |1-S

CD CDCD CD E

_>CCco

 _±;

C "S w

o c £ c'ro

co .£

C CD

o£

C 

O CD 'co">

C 3 

CD= i 

Q.CO |

CD-= CD c

-* ^ c co n ' 

co o>to =.t; .2 i

~~ c CD CD CO tS

^§ 5 »§. 1

§»^-i® x D-^C« «T3 0 

£~.E ^315 CD

^1^1 5

S"5o §'| «P

?^0 E 5 !

'ill !

CO "^ tj 

CD -*c

^ CO O

I.E 03° .52 co ora

CD_Q CD J5

CO C

li

CD'S

1

Z j

° "~ ! y o

£ ^

CD^

Q-c ^ o

^ '35 5 co

£

<J D) 

c co

(DC 

CO CD

Q.T3 

CD 

CO^

0°Sv

0_0

55 

ii

.Eg

M /CO 0)

co *- co! 0°

O O CD Q-T3

11 III

I

CD

Figure 25. Summary of structural and depositional events in the study area from late Early Cretaceous to late Oligocene 

time. Time lines are queried where the age of onset of an event is uncertain and are dashed to indicate local variations in the 

onset and duration of events.

REFERENCES CITED

Andersen, D.W., and Picard, M.D., 1974, Evolution of synorogenic clastic deposits in the intermontane Uinta basin of 

Utah, in Dickinson, W.R., ed., Tectonics and sedimentation:

Society of Economic Paleontologists and Mineralogists 

Special Publication 22, p. 167-189.

Bowers, W.E., 1972, The Canaan Peak, Pine Hollow, and Wasatch 

Formations in the Table Cliff region, Garfield County, 

Utah: U.S. Geological Survey Bulletin 1331-B, 39 p.

Paleogeographic Reconstructions, Colorado and Utah Q33
Bradley, W.H., 1930, The varves and climate of the Green River 

epochs: U.S. Geological Survey Professional Paper 158-E, 

p. 87-110.

____ 1931, Origin and microfossils of the oil shale of the Green 

River Formation of Colorado and Utah: U.S. Geological 

Survey Professional Paper 168, 58 p.

Bryant, Bruce, Naeser, C.W., Martin, R.F., and Mehnert, H.H., 

1989a, Upper Cretaceous and Paleogene sedimentary rocks 

and isotopic ages of Paleogene tuffs, Uinta basin, Utah: U.S. 

Geological Survey Bulletin 1787-J, 22 p.

____ 1989b, Ages of late Paleogene and Neogene tuffs and the 

beginning of rapid regional extension, eastern boundary of 

the Basin and Range province near Salt Lake City, Utah: 

U.S. Geological Survey Bulletin 1787-K, 12 p.

Bryant, Bruce, and Nichols, D.J., 1988, Late Mesozoic and Early 

Tertiary reactivation of an ancient crustal boundary along 

the Uinta trend and its interaction with the Sevier orogenic belt: Geological Society of America Memoir 171, 

p. 411-430.

Cashion, W.B., 1972, Geology and fuel resources of the Green 

River Formation, southeastern Uinta basin, Utah and 

Colorado: U.S. Geological Survey Professional Paper 548, 

48 p.

Clark, F.R., 1928, Economic geology of the Castlegate, Wellington, and Sunnyside quadrangles, Carbon County, Utah: 

U.S. Geological Survey Bulletin 793, 162 p.

Cobban, W.A., 1976, Ammonite record from the Mancos Shale of 

the Castle Valley-Price-Woodside area, east-central Utah: 

Brigham Young University Geology Studies, v. 22, pt. 3, 

p. 117-128.

Cobban, W.A., and Hook, S.C., 1984, Mid-Cretaceous molluscan 

biostratigraphy and paleogeography of southwestern part of 

Western Interior, United States, in Westerman, G.E.G., ed., 

Jurassic-Cretaceous biochronology and paleogeography of 

North America: Geological Association of Canada Special 

Paper 27, p. 257-271.

Cobban, W.A., and Kennedy, W.J., 1989, The ammonite Metengonoceras Hyatt, 1903, from the Mowry Shale (Cretaceous) 

of Montana and Wyoming: U.S Geological Survey Bulletin 

1787-L, 11 p.

Cole, R.D., 1987, Cretaceous rocks of the Dinosaur Triangle, in 

Averett, W.R., ed., Dinosaur Triangle Paleontological Field 

Trip: Grand Junction, Colo., Grand Junction Geological 

Society, p. 21-35.

Collins, B.A., 1976, Coal deposits of the Carbondale, Grand 

Hogback, and southern Danforth Hills coal fields, eastern 

Piceance basin, Colorado: Colorado School of Mines 

Quarterly, v. 71, no. 1, 138 p.

Cullins, H.L., 1968, Geologic map of the Banty Point quadrangle, 

Rio Blanco County, Colorado: U.S. Geological Survey 

Geologic Quadrangle Map GQ-703, scale 1:24,000.

Dyni, J.R., 1981, Geology of the nahcolite deposits and associated 

oil shales of the Green River Formation in the Piceance 

Creek Basin, Colorado: Boulder, Colo., University of 

Colorado Ph. D. thesis, 144 p.

Dyni, J.R., Milton, Charles, Jr., and Cashion, W.B., Jr., 1985, The 

saline facies of the upper part of the Green River Formation 

near Duchesne, Utah, in Picard, M.D., ed., Geology and 

energy resources, Uinta basin of Utah: Utah Geological 

Association Publication 12, p. 51-60.

Eaton, J.G., 1990, Stratigraphic revision of Campanian (Upper 

Cretaceous) rocks in the Henry Basin, Utah: The Mountain 

Geologist, v. 27, no. 1, p. 27-38.

Fenneman, N.M., and Gale, G.S., 1906, The Yampa coal field, 

Routt County, Colorado: U.S. Geological Survey Bulletin 

297, 96 p.

Fisher, D.J., Erdmann, C.E., and Reeside, J.B., Jr., 1960, 

Cretaceous and Tertiary formations of the Book Cliffs, 

Carbon, Emery, and Grand Counties, Utah, and Garfield 

and Mesa Counties, Colorado: U.S. Geological Survey 

Professional Paper 332, 80 p.

Fouch, T.D., 1976, Revision of the lower part of the Tertiary 

system in the central and western Uinta basin, Utah: U.S. 

Geological Survey Bulletin 1405-C, 7 p.

___ 1979, Character and paleogeographic distribution of 

Upper Cretaceous(?) and Paleogene nonmarine sedimentary 

rocks in east-central Nevada, in Armentrout, J.M., Cole, 

M.R., and TerBest, Harry, eds., Cenozoic paleogeography 

of the Western United States: Pacific Coast Section, Society 

of Economic Paleontologists and Mineralogists, Pacific 

Coast Paleogeography Symposium 3, p. 97-111.

____1981, Distribution of rock types, lithologic groups, and 

interpreted depositional environments for some lower Tertiary and Upper Cretaceous rocks from outcrops at Willow 

Creek-Indian Canyon through the subsurface of Duchesne 

and Altamont oil field: U.S. Geological Survey Oil and Gas 

Investigations Map Chart OC-81.

Fouch, T.D., and Cashion, W.B., 1979, Distribution of rock types, 

lithologic groups, and depositional environments for some 

lower Tertiary and Upper Cretaceous, and Upper and 

Middle Jurassic rocks in the subsurface between Altamont 

oil field and San Arroyo gas field, northcentral to northeastern Uinta basin, Utah: U.S. Geological Survey OpenFile Report 79-365, 2 sheets.

Fouch, T.D., Cashion, W.B., and Ryder, R.T., 1976, Field guide to 

lacustrine and related nonmarine depositional environments 

in Tertiary rocks, Uinta basin, Utah, in Epis, R.C., and 

Weimer, R.J., eds., Studies in Colorado field geology: 

Colorado School of Mines Professional Contributions 8, 

p. 358-384.

Fouch, T.D., Hanley, J.H., Forester, R.M., Keighin, C.W., Pitman, 

J.K., and Nichols, D.J., 1987, Chart showing lithology, 

mineralogy, and paleontology of the nonmarine North Horn 

Formation and Flagstaff Member of the Green River 

Formation, Price Canyon, central Utah A principal 

reference section: U.S. Geological Survey Miscellaneous 

Investigations Series Map I-1797-A.

Fouch, T.D., Lawton, T.F., Nichols, D.J., Cashion, W.B., and 

Cobban, W.A., 1983, Patterns and timing of synorogenic 

sedimentation in Upper Cretaceous rocks of central and 

northeast Utah, in Reynolds, M.W., and Dolly, E.D., eds., 

Mesozoic paleogeography of the west-central United States: 

Rocky Mountain Section, Society of Economic 

Paleontologists and Mineralogists, Rocky Mountain Paleogeography Symposium 2, p. 305-336.

Franczyk, K.J., and Nichols, D.J., 1988, Changing depositional 

systems reflecting foreland to intermontane basin transition 

in Campanian to Paleocene time, Book Cliffs and Wasatch 

Plateau, Utah: Geological Society of America Abstracts 

with Programs, v. 20, no. 7, p. 219.

Q34 Evolution of Sedimentary Basins Uinta and Piceance Basins
Franczyk, K.J., Pitman, J.K., Cashion, W.B., Dyni, J.R., Fouch, 

T.D., Johnson, R.C., Chan, M.A., Donnell, J.R., Lawton, 

T.F., and Remy, R.R., 1989, Evolution of resource-rich 

foreland and intermontane basins in eastern Utah and 

western Colorado: Washington, D.C., American Geophysical Union, 28th International Geological Congress Field 

Trip Guidebook T 324, 53 p.

Franczyk, K.J., Pitman, J.K., and Nichols, D.J., 1990, Sedirnentology, mineralogy, palynology, and depositional history of 

Upper Cretaceous and lower Tertiary rocks along the Utah 

Book and Roan Cliffs east of the Green River: U.S. 

Geological Survey Bulletin 1787-N, 27 p.

Gill, J.R., and Cobban, W.A., 1973, Stratigraphy and geologic 

history of the Montana Group and equivalent rocks, 

Montana, Wyoming, and North and South Dakota: U.S. 

Geological Survey Professional Paper 776, 37 p.

Gill, J.R., and Hail, W.J., Jr., 1975, Stratigraphic sections across 

Upper Cretaceous Mancos Shale-Mesaverde Group 

boundary, eastern Utah and western Colorado: U.S. 

Geological Survey Oil and Gas Investigations Chart OC-68.

Goldstrand, P.M., 1989, Provenance and paleogeographic 

implications of Late Cretaceous-Paleocene fluvial deposits 

of southwest Utah: Geological Society of America 

Abstracts with Programs, v. 21, no. 5, p. 85.

Hail, W.J., Jr., 1973, Geologic map of the Smizer Gulch 

quadrangle, Rio Blanco and Moffat Counties, Colorado: U.S. Geological Survey Geologic Quadrangle Map 

GQ-1131, scale 1:24,000.

Haq, B.U., Hardenbol, Jan, and Vail, P.R., 1987, Chronology of 

fluctuating sea level since the Triassic: Science, v. 235, 

p. 1156-1167.

Hobbs, R.S., 1989, The physical and magnetic polarity stratigraphy of the Upper Cretaceous-lower Tertiary North Horn 

and Flagstaff Formations, Gunnison Plateau, central Utah: 

Los Angeles, Calif., University of Southern California M.S. 

thesis, 162 p.

Isby, J.S., and Picard, M.D., 1983, Currant Creek Formation 

Record of tectonism in Sevier-Laramide erogenic belt: 

University of Wyoming Contributions to Geology, p. 91- 

108.

Jacobson, S.R., and Nichols, D.J., 1982, Palynological dating of 

syntectonic units in the Utah-Wyoming thrust belt The 

Evanston Formation, Echo Canyon Conglomerate, and 

Little Muddy Creek Conglomerate, in Powers, R.B., ed., 

Geologic studies of the Cordilleran thrust belt, Volume II: 

Rocky Mountain Association of Geologists, p. 735-750.

Johnson, R.C., 1984, New names for units in the lower part of the 

Green River Formation Piceance Creek basin, Colorado: 

U.S. Geological Survey Bulletin 1529-1, 20 p.

____ 1985, Early Cenozoic history of the Uinta and Piceance 

Creek basins, Utah and Colorado, with special reference to 

the development of Eocene Lake Uinta, in Flores, R.M., and 

Kaplan, S.S., eds., Cenozoic paleogeography of the westcentral United States: Rocky Mountain Section, Society of 

Economic Paleontologists and Mineralogists, p. 247-276.

____ 1989, Geologic history and hydrocarbon potential of Late 

Cretaceous-age, low-permeability reservoirs, Piceance 

basin, Western Colorado: U.S. Geological Survey Bulletin 

1787-E, 51 p.

Johnson, R.C., and May, Fred, 1978, Preliminary Stratigraphic 

studies of the upper part of the Mesaverde Group, the 

Wasatch Formation, and the lower part of the Green River 

Formation, DeBeque area, Colorado, including environments of deposition and investigation of palynomorph 

assemblages: U.S. Geological Survey Miscellaneous Field 

Studies Map MF-1050, 2 sheets.

____ 1980, A study of the Cretaceous-Tertiary unconformity in 

the Piceance Creek basin, Colorado; the Ohio Creek 

Formation (Upper Cretaceous) redefined as a member of the 

underlying Hunter Canyon or Mesaverde Formation: U.S. 

Geological Survey Bulletin 1482-B, 27 p.

Kellogg, H.E., 1977, Geology and petroleum of the Mancos B 

formation, Douglas Creek Arch area, Colorado and Utah, in 

Veal, H.K., ed., Exploration frontiers of the Central and 

Southern Rockies: Rocky Mountain Association of 

Geologists Symposium, p. 167-179.

LaRocque, A., 1960, Molluscan fauna of the Flagstaff formation of 

central Utah: Geological Society of America Memoir 78, 

100 p.

Lawton, T.F., 1986, Fluvial systems of the Upper Cretaceous 

Mesaverde Group and Paleocene North Horn Formation, 

central Utah; a record of transition from thin-skinned to 

thick-skinned deformation in the foreland region, in Peterson, J.A., ed., Paleotectonics and sedimentation in the 

Rocky Mountain Region, United States, Part III, Middle 

Rocky Mountains: American Association of Petroleum 

Geologists Memoir 41, p. 423-442.

____ 1989, Piggyback-basin deposits in the Sevier thrust belt, 

central Utah: Geological Society of America Abstracts with 

Programs, v. 21, no. 5, p. 104-105.

Lee, W.T., 1909, The Grand Mesa coal field, Colorado: U.S. 

Geological Survey Bulletin 341, pt. II, p. 316-334.

Lindsey, D.A., Naeser, C.W., and Shawe, D.R., 1975, Age of 

volcanism, intrusion, and mineralization in the Thomas 

Range, Keg and Desert Mountains, western Utah: U.S. 

Geological Survey Journal of Research, v. 3, no. 5, 

p. 597-604.

MacGinitie, H.D., 1969, The Eocene Green River flora of 

northwestern Colorado and northeastern Utah: University 

of California Publication of Geological Sciences, v. 83, 

p. 1-140.

Merewether, E.A., and Cobban, W.A., 1986, Biostratigraphic 

units and tectonism in the mid-Cretaceous foreland of 

Wyoming, Colorado, and adjoining area, in Peterson, J.A., 

ed., Paleotectonics and sedimentation in the Rocky 

Mountain region, United States, Part III, Middle Rocky 

Mountains: American Association of Petroleum Geologists 

Memoir 41, p. 443-467.

Merewether, E.A., Molenaar, C.M., and Cobban, W.A., 1983, Map 

and diagrams showing lithofacies and Stratigraphic 

nomenclature for formations of Turanian and Coniacian age 

in the middle Rocky Mountains, in Merewether, E.A., ed., 

Mid-Cretaceous Codell Sandstone Member of Carlile Shale, 

eastern Colorado: Society of Economic Paleontologists and 

Mineralogists, Rocky Mountain Section Spring Field Trip 

Guidebook, p. 19-25.

Molenaar, C.M., 1983, Major depositional cycles and regional 

correlations of Upper Cretaceous rocks, southern Colorado 

Plateau and adjacent area, in Reynolds, M.W., and

Paleogeographic Reconstructions, Colorado and Utah Q35
Dolly, E.D., eds., Mesozoic paleogeography of the 

west-central United States: Rocky Mountain Section, 

Society of Economic Paleontologists and Mineralogists, 

Rocky Mountain Paleogeography Symposium 2, p. 201- 

224.

Molenaar, C.M., and Cobban, W.A., 1991, Middle Cretaceous 

stratigraphy on the south and east sides of the Uinta basin, 

northeastern Utah and northwestern Colorado: U.S. 

Geological Survey Bulletin 1787-T, 34 p.

Mullet, D.J., 1989, Interpreting the early Tertiary Claron 

Formation of southern Utah: Geological Society of America 

Abstracts with Programs, v. 21, no. 5, p. 120.

Newman, K.T., 1974, Palynomorph zones in early Tertiary 

formations of the Piceance Creek and Uinta Basins, 

Colorado and Utah, in Murray, D.K., ed., Energy resources 

of the Piceance Creek Basin, Colorado: Rocky Mountain 

Association of Geologists Guidebook, 25th Field 

Conference, p. 47-55.

Newman, S.L., 1985, Sedimentary and depositional history of 

shallow shelf deposits within the Cretaceous Blackhawk 

Formation and Mancos Shale, east central Utah: Salt Lake 

City, Utah, University of Utah M.S. thesis, 158 p.

Nichols, D.J., and Bryant, Bruce, 1986, Palynology of the Currant 

Creek and Mesaverde Formations in the Currant CreekDuchesne River area, Duchesne and Wasatch Counties, 

Utah: U.S. Geological Survey Open-File Report 86-160, 

7 p.

Nichols, D.J., Jacobson, S.R., and Tschudy, R.H., 1982, Cretaceous palynomorph biozones for the central and northern 

Rocky Mountain region of the United States, in Powers, 

R.B., ed., Geologic studies of the Cordilleran thrust belt: 

Denver, Colo., Rocky Mountain Association of Geologists, 

v. 2, p. 721-733.

Nichols, D.J., and Ott, H.L., 1978, Biostratigraphy and evolution 

of the Momipites-Caryapollenites lineage in the early Tertiary in the Wind River basin, Wyoming: Palynology, v. 2, 

p. 93-112.

Obradovich, J.D., and Cobban, W.A., 1975, A time-scale for the 

Late Cretaceous of the Western Interior of North America, 

in Caldwell, W.G.E., ed., The Cretaceous system in the 

Western Interior of North America: Geological Association 

of Canada Special Paper 13, p. 31-54.

Obradovich, J.D., Mutschler, R.E., and Bryant, Bruce, 1969, 

Potassium-argon ages bearing on the igneous and tectonic 

history of the Elk Mountains and vicinity, Colorado A 

preliminary report: Geological Society of America Bulletin, 

v. 80, no. 9, p. 1749-1756.

Oetking, P., Feray, D.E., and Renfro, H.B., 1967, Map No. 2 

Geological highway map of the southern Rocky Mountain 

region: Tulsa, Okla., American Association of Petroleum 

Geologists, scale 1:1,800,000.

Peterson, Fred, Ryder, R.T., and Law, B.E., 1980, Stratigraphy, 

sedimentology, and regional relationships of the Cretaceous 

System in the Henry Mountains region, Utah, in Picard, 

M.D., ed., Henry Mountains symposium: Utah Geological 

Association Publication 8, p. 151-170.

Pfaff, B.J., 1985, Sedimentologic and tectonic evolution of the 

fluvial facies of the Upper Cretaceous Castlegate Sandstone, 

Book Cliffs, Utah: Salt Lake City, Utah, University of Utah 

M.S. thesis, 124 p.

Picard, M.D., 1985, Hypothesis of oil shale genesis, Green River 

Formation, northeast Utah, northwest Colorado, and southwest Wyoming, in Picard, M.D., ed., Geology and energy 

resources, Uinta basin of Utah: Utah Geological Association 

Publication 12, p. 193-210.

Renfro, H.B., and Feray, D.E., 1972, Map No. 5 Geological 

highway map of the northern Rocky Mountain region; 

Tulsa, Okla., American Association of Petroleum Geologists, scale 1:1,800,000.

Russon, M.P., 1987, Geology, depositional environments, and coal 

resources of the Helper 7Vi-minute quadrangle, Carbon 

County, Utah: Brigham Young University Geology Studies, 

v. 34, pt. l,p. 131-168.

Ryder, R.T., Fouch, T.D., and Elison, J.H., 1976, Early Tertiary 

sedimentation in the western Uinta basin, Utah: Geological 

Society of America Bulletin, v. 87, p. 496-512.

Smith, Curtis, 1983, Geology, depositional environments, and coal 

resources of the Mt. Pennell 2 NW quadrangle, Garfield 

County, Utah: Brigham Young University Geology Studies, 

v. 30, pt. 1, p. 145-169.

Spieker, E.M., 1946, Late Mesozoic and early Cenozoic history of 

central Utah: U.S. Geological Survey Professional Paper 

205-D, p. 117-161.

Stanley, K.O., and Collinson, J.W., 1979, Depositional history of 

the Paleocene-lower Eocene Flagstaff Limestone and coeval 

rocks, central Utah: American Association of Petroleum 

Geologists Bulletin, v. 63, no. 3, p. 311-323.

Stokes, W.L., 1986, Geology of Utah: Utah Museum of Natural 

History and the Utah Geological and Mineral Survey, 300 p.

Swift, D.L., Huddleston, P.M., Brenner, R.L., and Thompson, P., 

1987, Shelf construction in a foreland basin; storm beds, 

shelf sandbodies, and shelf-slope depositional sequences in 

the Upper Cretaceous Mesaverde Group, Book Cliffs, Utah: 

Sedimentology, v. 34, p. 423-458.

Tschudy, R.H., Tschudy, B.D., and Craig, L.C., 1984, Palynological evaluation of Cedar Mountain and Burro Canyon 

Formations, Colorado Plateau: U.S. Geological Survey 

Professional Paper 1281, 24 p.

Tweto, Ogden, 1975, Laramide (Late Cretaceous-early Tertiary) 

orogeny in the southern Rocky Mountains: Geological 

Society of America Memoir 144, p. 1-44.

Van de Graaff, F.R., 1972, Fluvial-deltaic facies of the Castlegate 

Sandstone (Cretaceous), east-central Utah: Journal of Sedimentary Petrology, v. 42, no. 3, p. 558-571.

Weimer, R.J., and Sonnenberg, S.A., 1983, Codell Sandstone, new 

exploration play, Denver basin, in Mid-Cretaceous Codell 

Sandstone Member of Carlile Shale, eastern Colorado: 

Society of Economic Paleontologists and Mineralogists 

Rocky Mountain Section, Spring Field Trip Guidebook, 

p. 26-48.

Weiss, M.P., 1982, Relation of the Crazy Hollow Formation to the 

Green River Formation, central Utah, in Nielson, D.L., ed., 

Overthrust belt of Utah: Utah Geological Association 

Publication 10, p. 285-289.

Wells, N.A., 1983, Carbonate deposition, physical limnology, and 

environmentally controlled chert formation in PaleoceneEocene Lake Flagstaff, central Utah: Sedimentary Geology, 

v. 35, no. 5, p. 263-296.

Q36 Evolution of Sedimentary Basins Uinta and Piceance Basins
Witkind, I.J., and Marvin, R.F., 1989, Significance of new 

potassium-argon ages from the Goldens Ranch and Moroni 

Formations, Sanpete-Sevier Valley area, central Utah: Geological Society of America Bulletin, v. 101, no. 4, p. 534 

548.

Witkind, I.J., Standlee, L.A., and Maley, K.F., 1986, Age and 

correlation of Cretaceous rocks previously assigned to the 

Morrison(?) Formation, Sanpete-Sevier Valley area, central 

Utah: U.S. Geological Survey Bulletin 1584, 9 p.

Witkind, I.J., Weiss, M.P., and Brown, T.L., 1987, Geologic map 

of the Manti 30'x60' quadrangle, Emery, Juab, Sanpete, and

Sevier Counties, Utah: U.S. Geological Survey Miscellaneous Investigations Series Map 1-1631, scale 1:100,000.

Wolfe, J.A., and Upchurch, G.R., 1987, North American nonmarine climates and vegetation during the Late Cretaceous: 

Palaeogeography, Palaeoclimatology, Palaeoecology, v. 61, 

p. 33-77.

Zapp, A.D., and Cobban, W.A., 1960, Some Late Cretaceous 

strand lines in northwestern Colorado and northeastern 

Utah: U.S. Geological Survey Professional Paper 400-B, 

p. B246-B249.

6U.S. GOVERNMENT PRINTING OFFICE: 1992-673-049/46052 Paleogeographic Reconstructions, Colorado and Utah Q37



SELECTED SERIES OF U.S. GEOLOGICAL SURVEY PUBLICATIONS

Periodicals

Earthquakes & Volcanoes (issued bimonthly). 

Preliminary Determination of Epicenters (issued monthly).

Technical Books and Reports

Professional Papers are mainly comprehensive scientific reports 

of wide and lasting interest and importance to professional scientists and 

engineers. Included are reports on the results of resource studies and of 

topographic, hydrologic, and geologic investigations. They also include 

collections of related papers addressing different aspects of a single scientific topic.

Bulletins contain significant data and interpretations that are of 

lasting scientific interest but are generally more limited in scope or geographic coverage than Professional Papers. They include the results of 

resource studies and of geologic and topographic investigations; as well 

as collections of short papers related to a specific topic.

Water-Supply Papers are comprehensive reports that present significant interpretive results of hydrologic investigations of wide interest 

to professional geologists, hydrologists, and engineers. The series covers 

investigations in all phases of hydrology, including hydrology, availability of water, quality of water, and use of water.

Circulars present administrative information or important scientific information of wide popular interest in a format designed for distribution at no cost to the public. Information is usually of short-term interest.

Water-Resources Investigations Reports are papers of an interpretive nature made available to the public outside the formal USGS publications series. Copies are reproduced on request unlike formal USGS 

publications, and they are also available for public inspection at depositories indicated in USGS catalogs.

Open-File Reports include unpublished manuscript reports, maps, 

and other material that are made available for public consultation at depositories. They are a nonpermanent form of publication that maybe cited in other publications as sources of information.

Maps

Geologic Quadrangle Maps are multicolor geologic maps on topographic bases in 7 1/2- or 15-minute quadrangle formats (scales mainly 1:24,000 or 1:62,500) showing bedrock, surficial, or engineering 

geology. Maps generally include brief texts; some maps include structure 

and columnar sections only.

Geophysical Investigations Maps are on topographic or planimetric bases at various scales, they show results of surveys using geophysical techniques, such as gravity, magnetic, seismic, or radioactivity, which 

reflect subsurface structures that are of economic or geologic significance. Many maps include correlations with the geology.

Miscellaneous Investigations Series Maps are on planimetric or 

topographic bases of regular and irregular areas at various scales; they 

present a wide variety of format and subject matter. The series also includes 7 1/2-minute quadrangle photogeologic maps on planimetric 

bases which show geology as interpreted from aerial photographs. The 

series also includes maps of Mars and the Moon.

Coal Investigations Maps are geologic maps on topographic or 

planimetric bases at various scales showing bedrock or surficial geology, 

stratigraphy, and structural relations in certain coal-resource areas.

Oil and Gas Investigations Charts show stratigraphic information for certain oil and gas fields and other areas having petroleum potential.

Miscellaneous Field Studies Maps are multicolor or black-andwhite maps on topographic or planimetric bases on quadrangle or irregular areas at various scales. Pre-1971 maps show bedrock geology in relation to specific mining or mineral-deposit problems; post-1971 maps 

are primarily black-and-white maps on various subjects such as environmental studies or wilderness mineral investigations.

Hydrologic Investigations Atlases are multicolored or black-andwhite maps on topographic or planimetric bases presenting a wide range 

of geohydrologic data of both regular and irregular areas; the principal 

scale is 1:24,000, and regional studies are at 1:250,000 scale or smaller.

Catalogs

Permanent catalogs, as well as some others, giving comprehensive 

listings of U.S. Geological Survey publications are available under the 

conditions indicated below from the U.S. Geological Survey, Books and 

Open-File Reports Sales, Box 25286, Denver, CO 80225. (See latest 

Price and Availability List.)

"Publications of the Geological Survey, 1879-1961" may be purchased by mail and over the counter in paperback book form and as a set 

microfiche.

"Publications of the Geological Survey, 1962-1970" may be purchased by mail and over the counter in paperback book form and as a set 

of microfiche.

"Publications of the U.S. Geological Survey, 1971-1981" may be 

purchased by mail and over the counter in paperback book form (two 

volumes, publications listing and index) and as a set of microfiche.

Supplements for 1982, 1983, 1984, 1985, 1986, and for subsequent years since the last permanent catalog may be purchased by mail 

and over the counter in paperback book form.

State catalogs, "List of U.S. Geological Survey Geologic and Water-Supply Reports and Maps For (State)," may be purchased by mail and 

over the counter in paperback booklet form only.

"Price and Availability List of U.S. Geological Survey Publications," issued annually, is available free of charge in paperback booklet 

form only.

Selected copies of a monthly catalog "New Publications of the 

U.S. Geological Survey" is available free of charge by mail or may be 

obtained over the counter in paperback booklet form only. Those wishing 

a free subscription to the monthly catalog "New Publications of the U.S. 

Geological Survey" should write to the U.S. Geological Survey, 582 National Center, Reston, VA 22092.

Note.-Prices of Government publications listed in older catalogs, 

announcements, and publications may be incorrect. Therefore, the prices 

charged may differ from the prices in catalogs, announcements, and publications.