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GEOLOGICAL RESOURCE AREA |GRA) 2

BLM LIBRARY
I I III III!

1 8{

88026533

FINAL REPORT

PHASE 1: GEM

(GEOLOGICAL, ENERGY and MINERALS)

RESOURCE ASSESSMENT FOR
REGION 4, COLORADO PLATEAU

DENVER

cov°»

N»

•OURANQO

SUBMITTED TO:

U.S. DEPARTMENT OF THE INTERIOR

BUREAU OF LAND MANAGEMENT

DENVER SERVICE CENTER

DENVER, COLORADO 80225

ill!*.

dSLjfp MSME/WALLABY ENTERPRISES

^Bl" A JOINT VENTURE OF

MOUNTAIN STATES MINERAL ENTERPRISES. INC.
and WALLABY ENTERPRISES, INC.

D-553A, Building 50 Q.</7

D«nv0r Federal Center /<?, =>

P0. Box 25047 l(&
Denver, CO 80225-0047

FINAL REPORT

PHASE 1: GEM

(GEOLOGICAL, ENERGY and MINERALS)

RESOURCE ASSESSMENT FOR
REGION 4, COLORADO PLATEAU

BULL CANYON

DINOSAUR NATIONAL MONUMENT ADJACENT - NORTH, AREA

GRA 2

SUBMITTED TO:

U.S. DEPARTMENT OF THE INTERIOR

BUREAU OF LAND MANAGEMENT

DENVER SERVICE CENTER

DENVER, COLORADO 80225

MAY 1983

dm MSME/WALLABY ENTERPRISES

~lr A JOINT VENTURE OF

MOUNTAIN STATES MINERAL ENTERPRISES, INC.
and WALLABY ENTERPRISES, INC.

TABLE OF CONTENTS

SECTION PAGE

FOREWORD i

EXECUTIVE SUMMARY ii

I INTRODUCTION 1-1

II GEOLOGY II-l

Physiography II-l

Rock Units II-l

Structural Geology and Tectonics II-A

Paleontology II-5

Historical Geology II-7

III ENERGY AND MINERAL RESOURCES III-l

Known Mineral Deposits III-l

Known Prospects, Mineral Occurrences, and

Mineralized Areas III-2

Mining Claims, Leases, and Material Sites . . III-3

Mineral Deposit Types III-3

Mineral Economics III-5

IV LAND CLASSIFICATION FOR GEM RESOURCES POTENTIAL . . IV-1

Leasable Resources IV-4

Locatable Resources IV-7

Salable Resources IV-13

V RECOMMENDATIONS FOR ADDITIONAL WORK V-l

VI REFERENCES AND SELECTED BIBLIOGRAPHY VI- 1

APPENDICES (SEPARATE ATTACHMENTS)

FOREWORD

This report is one of a series of eleven reports addressing the Wilderness Study
Areas (WSA's) located in what has been designated as the Colorado Plateau, Region
4, by the Bureau of Land Management (BLM), Denver Federal Center. The study was
under the direction of Mr. Robert J. Coker, the Contracting Officer's Authorized
Representative (COAR).

The WSA's have been segregated into eleven G-E-M (Geology, Energy, Minerals)
Resources Areas (GRA's). Each designated GRA constitutes one report. The purpose
of these reports is to assess the potential for geology, energy and mineral (GEM)
resources existing within a WSA and GRA. This information will then be used by BLM
geologists in completing the assessment for GEM resources potential within the
WSA's, and for the integration with other resource data for the decision on suita-
bility for recommendation of the respective WSA.

The reports were developed and prepared by the Joint Venture team of MSME/Wallaby
Enterprises, Tucson, Arizona, by Patricia J. Popp (Geologist), and Barbara J. Howie
(Geologist) under the direction of Eric A. Nordhausen (Project Manager) and Richard
Lundin (Principal Investigator), under BLM Contract No. YA-553-CT2-1041 .

Consulting support was provided by a highly specialized geological team composed
of: Ted Eyde, Dr. Paul Gilmour, Dr. Robert Carpenter, Dr. Donald Gentry, Dr. Edger
Heylmun, Dr. Larry Lepley, Annon Cook, Walter Heinrichs, Jr., and Charles Campbell.
Their contribution is both acknowledged and appreciated. The work of Dr. Gilmour,
Dr. Carpenter and Dr. Lepley should receive special acknowledgement. It was from
the work of these consultants that this report on the Bull Canyon/Dinosaur National
Monument Adjacent-North GRA was able to be completed.

EXECUTIVE SUMMARY

The BLM has adopted a two-phase procedure for the integration of geological, energy
and minerals (GEM) resources data for suitable/nonsuitable decisions for Wilderness
Study Areas (WSA's). The two-phased approach permits termination of a GEM resour-
ces data gathering effort at the end of Phase One. The objective of this Phase One
GEM resources assessment is the evaluation of existing data (both published and
available unpublished data) and their interpretation for the GEM resources poten-
tial of the WSA's incuded in each region. Phase Two is designed to generate new
data needed to support GEM resources recommendations.

Over 10 million acres of WSA's require GEM resources data input. These WSA's are
unequally distributed in eleven western states of the coterminous United States.
The WSA's are grouped in six large regional areas. The WSA's within the western
part of Colorado, and a few crossing into Utah, were included as Region 4, also
known as the Colorado Plateau Region. Except for one small area at the southwest
extreme of the region and another at the north extreme, the region is within the
northern half of the known Colorado Plateau physiographic province.

The 32 WSA's within Region 4 encompass 474,620 acres. These have been
geographically segregated within 11 designated GEM Resource Areas (GRA's). This
report addresses the Bull Canyon/Dinosaur National Monument Adjacent-North area,
GRA 2. Within the GRA is the Bull Canyon WSA (CO-010-001 & UT-080-419), and
Dinosaur Adjacent-North (Unit 224: CO-010-224; Unit 224A: CO-010-224A; Unit 226:
CO-010-226; Unit 228: CO-010-228; Unit 229D: CO-010-229D) .

The geology of the GRA consists of gentle mountain and valley areas, cut in part by
the Yampa River. The rocks are mostly sedimentary, containing mineralized areas.
In addition, faults In the area have acted to mineralize base and precious metals.

The mineral resources of the GRA include coal, uranium, base and precious metals,
construction stone, clay, and sand and gravel. The coal, uranium, construction
stone, and clay occur in various formations of sedimentary rocks. Copper, lead,
zinc, iron, manganese, and silver are found localized by faults that occur in the
GRA.

The WSA's (see Figure 1-1 and Overlay A) in the GRA consist mostly of sedimentary
formations with little or no mineralization. Unit C0- 010-226, which contains cop-
per mineralization in a faulted zone, is the only block in Dinosaur Adjacent-North
WSA to have mineralization. Bull Canyon WSA does not have any known deposits.

The classification for the occurrences of leasable minerals, locatable and salable
resources varies. Due to lack of published literature and geologic field
information, there is an unknown potential for leasable resources in the GRA.
There is moderate favorability for locatable resources (base and precious metals)
in the Dinosaur Ad jacentNorth WSA, and an unknown potential in Bull Canyon.
Dinosaur Adjacent- North WSA has a high favorability for salable dimension stone,
cement rock, and moderate favorability for mineral pigments and high calcium
limestone. Bull Canyon WSA has low favorability for salable resources.

Overall, it is recommended that each WSA in the GRA receive additional work to
determine the full economic potential of each area. This work should include
further research in the unpublished and proprietary literature, a detailed program
of geologic mapping and sampling, and additional geochemical and stratigraphic
studies to confirm the occurrence or lack of occurrence of geology, energy or
mineralized commodities.

iii

SECTION I
INTRODUCTION

The Bull Canyon/Dinosaur National Monument Adjacent-North GRA (Figure 1-1) is
located in western Moffat County, Colorado and eastern Uintah Counties, Utah. The
GRA encompasses six WSA's; CO-010-001/UT-080-419, CO-010-224, CO-010-224A,
CO-010226, CO-010-228 and CO-010-229D.

The GRA area is located approximately 100 miles northwest of Grand Junction, Colo-
rado, and 20 miles east of Vernal, Utah. Located within the GRA are a number of
settlements that are local supply centers for agriculture, ranching, and mining
activities in the area. The towns are supplied by road networks from Grand Junc-
tion and Vernal, the nearest regional supply centers. These towns (Dinosaur,
Wiley's Resort, Blue Mountain, Skull Creek, and Massadonia), are also local supply
centers for the oil and gas operations in the area.

The GRA encompasses all or portions of Townships 3-8 North, Ranges 99-104 West; and
Townships 3-7 South, Range 26 West in Utah. The entire area is bounded by west
Longitudes 108° 28' 03" and 109° 08' 00" and north Latitudes 40° 15' 00" and 40°
36' 05". It contains approximately 801.2 square miles (2155 square kilometers or
512,770 acres) of Federal, state and private lands. The Bureau of Land Management
portion of these holdings are under the jurisdiction of the Little Snake and White
River Resource Area Offices of the Craig District Office.

The specific WSA's within the GRA have a total of 34,937 acres of Federal land.
The acreages of the various contained WSA's are:

Bull Canyon WSA (CO-010-001/UT-080-419) - 12,297 acres
Dinosaur Adjacent-North WSA's:

(CO-010-224) - 4,340 acres

(CO-010-224A) - 1,320 acres

(CO-010-226) - 4,880 acres

(CO-010-228) - 5,200 acres

(C0-010-229D) - 6,900 acres

The Bull Canyon WSA is located in the southwestern part of the GRA and is adjacent
to the western boundary of Dinosaur National Monument. The rest of the WSA units
are in the northeastern portion of the GRA and are directly adjacent to the
northern boundary of Dinosaur National Monument (See Overlay A).

Due to the lack of available data on each WSA, emphasis was placed on gaining an
understanding of the mineral potential of each WSA within the GRA. Information on
the mineral resources of GRA was utilized to extrapolate and estimate the poten-
tials of the contained WSA's from the existing data that in most cases, referred
only indirectly to the WSA's. The purpose of this contract was to utilize the
known geological information within each WSA and GRA to ascertain the GEM resource
potential of the WSA's. The known areas of mineralization and claims have been
plotted as overlays to Figure 1-1.

1-1

The information contained in this report was obtained from published literature,
computerized data base sources, Bureau of Land Management File Data, company files
and returned data sheets. The information was compiled into a series of files on
each WSA and a series of maps that covered the entire western portion of Colorado.
After a thorough review of the existing data, a program of field checking was
carried out by MSME/Wallaby ' s team of experts. Field investigations in the GRA
were carried out by Dr. Paul Gilmour, and Dr. Robert Carpenter on September 2,
1982.

Both of these individuals are registered professional geologists and associates of
MSME/Wallaby. Further analysis and study was provided through the photographic
interpretation services of BLM 1:24,000 aerial photos by Dr. Larry Lepley, regis-
tered professional geologist and remote sensing specialist. The aerial photos used
are included in Appendix A.

1-2

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CO -010 -229 D

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CO 010 226

CO-010-224 A

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EXPLANATION

Quaternary

(Approximately

2 million years

Qac

before present

(mybp) to

present)

Qop

Qtg

Tertiary

Tbb

(Approximately

62-2 mybp)

Tbp

Tbc

Tds

Tdl

Tdd

Tdb

Tuu

Tul

Tbu

Tbl

Tgp

-m-

Tgl

Tgla

Tgw

Tgt

Tglu

Twc

Twn

Twm

Cretaceous

Kmvg

(Approximately

Kmvu

135-62 mybp)

Kmvc

Kmvl

Kmv

Ksc

Kbc

Kw
Ki
Kla

Eolian deposits

Alluvium

Alluvium and colluvium

Piedmont-slope deposits

Fan deposits and colluvium

Land slide deposits

River-terrace deposits

Old piedmont-slope deposits

Old gravel deposits

Browns Park. Formation and/or

Bishop Conglomerate
Browns Park Formation
Bishop Conglomerate

Duchesne River Formation, Starr Flat Member
Duchesne River Formation, LaPoint Member
Duchesne River Formation, Dry Gulch Creek Member
Duchesne River Formation, Brennan Basin Member
Uinta Formation
Uinta Formation-upper part
Uinta Formation-lower part
Bridger Formation
Bridger Formation-upper part
Bridger Formation- lower part
Green River Formation
Parachute Creek Member
Mahogany ledge
Garden Gulch, Douglas Creek, and Anvil Points

Members
Laney Member
Wilkins Peak Member
Tipton Tongue
Luman Tongue
Wasatch Formation
Cathedral Bluffs Tongue
Niland Tongue
Main body
Fort Union Formation

Mesaverde Group, undivided

Mesaverde Group-upper unit

Mesaverde Group-coal unit

Mesaverde Group-lower unit

Mesaverde Group-upper, coal, and lower unit

Sego Sandstone, Buck Tongue of Mancos Shale, and

Castlegate Sandstone
Buck Tongue of Mancos Shale and Castlegate

Sandstone
Williams Fork Formation
lies Formation
Lance Formation and Fox Hills Sandstone

1-4

EXPLANATION (cont)

Cretaceous (cont)

Cretaceous
and Jurassic

Kle Lewis Shale

Km Mancos Shale

Kh Hilliard Shale

Kfd Frontier Sandstone and Mowry Shale Members of

Mancos Shale, and Dakota Sandstone
KJcm Cedar Mountain Formation (lower Cretaceous) and

Morrison Formation (upper Jurassic)
Kc Cedar Mountain Formation

KJmsc Cedar Mountain Formation, Morrison Formation,

Stump Formation, Entrada Sandstone, and Carmel
Formation

Jurassic

(Approximately

Jmsc

195-135 mybp)

Jmsc

Jsc

Lower Jurassic

JTrgc

and Upper Jurassic

JTrg

Triassic

Trc

(Approximately

TrPmp

225-195 mybp)

Trm

Trmd

Trd

Morrison Formation

Morrison Formation, Stump Formation and Entrada

Sandstone
Morrison Formation, Stump Formation, Entrada

Sandstone, and Carmel Formation
Stump Formation, Entrada Sandstone, and Carmel

Formation
Stump Formation and Entrada Sandstone

Glen Canyon Sandstone and Chinle Formation
Glen Canyon Sandstone

Chinle Formation - Gartra Member

Moenkopi Formation (lower Triassic) and Park City

Formation (Permian)
Moenkopi Formation

Moenkopi Formation and Dinwoody Formation
Dinwoody Formation

Permian
(approximately
280-225 mybp)

Pennsylvanian
(Approximately
320-280 mybp)

Mississippian
(Approximately
342-320 mybp)

PPw
PPM
PPmr

Park City Formation

Weber Sandstone

Morgan Formation

Morgan Formation and Round Valley Limestone

Mississippian rocks

Cambrian
(Approximately
600-500 mybp)

Precambrian
Approximately
3400-600 mybp)

Yu
Wr

Lodore Formation

Uinta Mountain Group
Red Creek Quartzite

1-5

LEGEND

C..Z) -0 OIL FIELD ■

C..D "G GAS FIELD

D
C_J -Os OIL SHALE

' x

( ) -C COAL REGION

>—

• OIL WELL ^
-£ OIL a GAS WELL B
-#■ GAS WELL ^

• SHOW OF GAS 0

3 SHOW OF OIL ^

>4r show of oil a gas ^

• -C COAL DEPOSIT .„
O -C COAL OCCURRENCE

A SHUT-IN WELL X

0 C02 OR He=HELIUM -RICH 0

WELL

A DRY WELL-ABANDONED

Y ®

Cm MILL

n PLANT O

r\ NATURAL GAS PROCESSING (|

UQ PLANT

ffift REFINERY

0 OIL Ck LIGNITE

G GAS CP PEAT

Os OIL SHALE A9 SILVER

Oi TAR SANDS Au GOLD

Gi GILSONITE Cu COPPER

C COAL CI CLAY

1-6

MINERAL OREBOO Y

MINERAL DEPOS IT

MINERAL OCCURRENCE

PROSPECT

ACCESSIBLE AD IT

INACCESSIBLE AD IT

VERTICAL SHAFT

INCLINED SHAFT

MINE TYPE UNKNOWN

ACTIVE OPEN PIT, OR QUARRY

INACTIVE OPEN PIT, OR QUARRY

ACTIVE GRAVEL OR
CLAY (CI) PIT

INACTIVE GRAVEL OR
CLAY (CI) PIT

EXPLORATION HOLE WITH
DATA AVAILABLE

EXPLORATION HOLE WITHOUT
DATA AVAILABLE

UNPATENTED MINING CLAIM
PATENTED MINING CLAIM

MINERAL OR OIL a GAS LEASE

Ds DIMENSION STONE

Fc IRON

Mn MANGANESE

Pb LEAD

U URANIUM

V VANADIUM

Zn ZINC

SECTION II
GEOLOGY

PHYSIOGRAPHY

Within the GRA boundary (see Figure 1-1) are mountain and valley areas adjacent to
Dinosaur National Monument. The valley of the Yampa River is the prominent topo-
graphic figure cutting through the National Monument. The course of the Yampa
divides the GRA into two distinct north and south portions. The area directly
north of the National Monument consists of ridges and draws that drain northward
into the Rye Grass Creek, and Douglas Draw areas. Also within this area are a ser-
ies of southward draining tributaries of the Yampa River. The topographic relief
is approximately 2,000 feet. South of the river, the terrain consists of valleys
with occasional mountain ridges and mesa tops. A prominant east-west valley cuts
through the area in the south-central portion of the GRA. A few north-south and
northeast trending stream systems cut through the southern portion of the GRA and
isolate some of the more prominent topographic features (Round Top Mountain,
Martha's Peak, Tanks Peak and Blue Mountain). These drainage systems (Disappoint-
ment Draw, Hell's Canyon and Wolf's Creek), have canyons associated with them where
they cut through ridge or mesa top areas. The vertical relief in this southern
portion of the GRA ranges from 200 to 2,000 feet.

The following addresses the physiography of each of the WSA's in the Bull Canyon-
Dinosaur National Monument Adjacent-North GRA.

BULL CANYON WSA (C0-010-001/UT-080-419)

This WSA includes a small portion of the upper drainage of Cliff Trail Creek and is

characterized by a shallow canyon along the creek drainage. The vertical relief

within the WSA is less than 500 feet. This unit, located in Utah, is 20 miles
southeast of Vernal, Utah.

DINOSAUR ADJACENT-NORTH WSA'S (CO-010-224, 224A, 226, 228, 229D)

These WSA's are located upland from Dinosaur National Monument's river canyons
along Douglas Mountain. They consist primarily of portions of ridges, draws, and
gently rolling valley areas. Some of the units have high, prominant ridges that
rise to 8,000 feet in elevation. All of the units are directly adjacent to the
northern boundary of Dinosaur National Monument, and are approximately 50-75 miles
northeast of Vernal, Utah. Vertical relief within the unit areas is approximately
3,000 feet.

ROCK UNITS

Within the Bull Canyon/Dinosaur National Monument Adjacent-North, GRA is found a
variety of rock units that represent a large part of Precambrian, Paleozoic,
Mesozoic and Cenezoic time.

II-l

The Precambrian is mainly represented by the marine sandstone and silty shale units
of the younger Precambrian Uinta Mountain Group. This series of units unconforma-
bly overlies the Red Creek Quartzite. The Red Creek. Quartzite outcrops within the
GRA but has only been mapped north and west of Browns Park (Rowley et al, 1979),
and is considered to be the underlying basement complex. The Red Creek Quartzite
is composed of deformed beds of metaquartzite , amphibolite, minor marble and intru-
sive felsic igneous rocks (Rowley et al , 1979; Gilmour, Personal Communication,
1982). Spotty copper-iron and uranium mineralization has been reported from this
unit in Utah. (Unterman et al, 1954).

The Cambrian Lodore Formation outcrops in the northeast portion of the GRA and con-
sists of a series of marine sandstone, shale and conglomerate units that are occa-
sionally fossiliferous at or near the Lodore-Madison contact in other areas of
Colorado (Rowley et al , 1979; Carpenter, Personal Communication, 1982; Gilmour,
Personal Communication, 1982).

The Mississippian Madison Formation is usually found in contact with the Lodore and
is characterized as a fossiliferous and cherty marine limestone with local dolorait-
ic units (Rowley et al, 1979). In areas near Douglas Mountain, small base and pre-
cious metal replacement deposits have been noted in this unit (Unterman et al,
1954; Carpenter, Personal Communication, 1982). Other Missippian units that out-
crop within the GRA include the shale, sandstone and limestone units of the Humbug
Formation and the continental and marine shale-sandstone-limestone members of the
Doughnut Shale (Rowley et al, 1979).

The Pennsylvania Round Valley Formation represents a sequence of marine limestone
units with interbedded shale. The unit is moderately fossiliferous and is directly
overlain by the sandstone, shale and fossiliferous limestone members of the Morgan
Formation. The Morgan Formation is known to contain base and precious mineraliza-
tion (mainly copper-silver-iron-manganese) within the GRA in basal conglomerate
units (Unterman et al, 1954; Carpenter, Personal Communication, 1982; Rowley et
al, 1979; Vanderwilt, 1947). It is considered to be a marine sequence that is in
conformable contact with the overlying Pennsylvania Weber Sandstone Formation. The
Weber consists of a series of eolian and marine sandstone units that are thought to
represent a near-shore dune environment (Rowley et al, 1979; Unterman et al,
1954).

Outcrops of the Permian Park City Formation are found in the extreme southwest cor-
ner of the GRA. This formation, deposited in areas to the west of the GRA, is com-
posed of a series of limestone, sandstone, shale, siltstone, dolomite and phosphat-
ic shale units that represent a period of marine deposition in a restricted basin
environment (Rowley et al, 1979; Unterman et al, 1954). Commercial thicknesses of
the phosphate bearing units have been reported in areas to the west and south of
the GRA (Unterman et al, 1954; Eyde, Personal Communication, 1982). In the north-
east portion of the GRA, the Park City is absent from the section and the Pennsyl-
vania section is directly overlain by the Mesozoic section.

Pre-Cretaceous Mesozoic units that are known to exist within the GRA are the Trias-
sic Moenkopi and Chinle Formations, the Triassic- Jurassic Glen Canyon Formation,
and the Jurassic Stump, Entrada Sandstone, Carmel and Morrison Formations (Rowley
et al, 1979). The Triassic Moenkopi Formation consists of a series of shale and
siltstone units that are thought to be of continental and marine origin. Minor

II-2

gypsum beds are locally found within sandy portions of the stratigraphy (Rowley et
al, 1979). Directly overlying the Moenkopi is the Chinle Formation. In northern
Colorado and Utah, the Chinle is a fine grained series of fluvial and lacustrine
siltstones, sandstones, claystones and shale. Within the GRA the basal Gartra Mem-
ber is usually found as a cross-bedded fluvial sandstone and conglomerate unit.
The Gartra Member may be equivalent to the Triassic Shinarump Formation of southern
Utah and Arizona, known to contain significant uranium-vanadium deposits (Rowley et
al, 1979; Unterman et al, 1954). The Triassic- Jurassic Glen Canyon Formation crops
out in only the northeast part of the GRA and is a strongly bedded eolian sandstone
unit (Rowley et al, 1979).

The (pre-Mesaverde) Cretaceous units that crop out within the GRA include the Cedar
Mountain, Dakota Sandstone, Mowry Shale, Frontier Sandstone, Hilliard Shale, and
Mancos Shale Formations or Members. The Cedar Mountain Formation consists of a
series of fluvial mudstone, shale, siltstone, conglomerate and limestone units.
The overlying Dakota Sandstone is made up of sandstone, shale and conglomerate
units with thin beds of coal and carbonaceous shale. The coal units of the Dakota
Sandstone are locally important but thin and discontinuous (Gentry, Personal Com-
munication, 1982; Rowley et al, 1979; Unterman et al , 1954). The Mowry Shale Mem-
ber of the Mancos Shale is a siliceous marine shale with abundant fossil material.
The Frontier Sandstone Member of the Mancos Shale is a crossbedded sandstone unit
that contains minor carbonaceous shale and coal beds which are of minor economic
important (Rowley et al, 1979; Gentry, Personal Communication, 1982). The Hilliard
Shale Formation consists of a single thick marine shale unit with minor sandstone.
The overlying Mancos Shale Formation is also a single thick marine shale unit. It
contains minor siltstone and sandstone units (Rowley et al , 1979).

Within the GRA the Mesaverde Formation crops out as a series of shale, carbonaceous
shale, sandstone and coal units (Rowley et al , 1976). Within the GRA and in other
areas of Colorado the coal members of this unit are being mined (Vanderwilt, 1947;
Gentry, Personal Communication, 1982).

Tertiary units that crop out within the GRA include units of the Wasatch, Green
River, Bishop Conglomerate and Browns Park Formations (Rowley et al , 1979). The
Wasatch Formation units that crop out within the GRA include shale, siltstone,
claystone, coal, sandstone and carbonaceous shale units which are thought to be of
fluvial or lacustrine origin. The Wasatch Formation intertongues with the Green
River sequence of marlstone, shale, oil shale, limestone, siltstone, sandstone and
fluvial conglomerate units (Rowley et al, 1979). The Bishop Conglomerate consists
of sandstone, conglomerate siltstone, rhyolitic tuff, and limestone units and is
thought to represent a volcanic unit that was reworked in a fluvial and eolian
environment. The Browns Park Formation directly overlies the Bishop Conglomerate
and consists of sandstone, tuff and limestone units and is thought to be a part of
volcanic cycle that was active in Miocene time. The clastic units appear to be
reworked volcanic material and locally contain minor amounts of uranium and vanadi-
um mineralization in association with devitrified tuffaceous unit (Rowley et al ,
1979; Carpenter, Personal Communication, 1982).

Quaternary piedmont, alluvial, landslide, and river terrace deposits are found
overlying the exposed Precambrian, Paleozoic, Mesozoic and Tertiary stratigraphy.

II-3

STRUCTURAL GEOLOGY AND TECTONICS

Tectonic features found within the GRA include a few mapped high angle faults and
joint systems in the northeast and east-central portions of the GRA. These west-
northwest and east-northeast striking features parallel the axial planes of the
numerous anticlinal and synclinal structures that are found in the area (Rowley et
al, 1979). Some of the fold features mapped in the area of the GRA may have impor-
tance in the localization of oil, gas, and uranium deposits (Heylmun, Personal Com-
munication, 1982; Carpenter, Personal Communication, 1982).

In the Blue Mountain and Skull Creek areas faulting may have localized copper,
lead, zinc, manganese and uranium deposits (Aurand, 1920; Carpenter, Personal Com-
munication, 1982).

In the southern portion of the GRA, the Split Mountain, Blue Mountain (Willow
Creek), and the Skull Creek (Blue Mountain) anticlinal structures have arched por-
tions of the Paleozoic and Mesozoic sections, and may have been caused by the low
angle thrust fault that has been mapped in the vicinity of Round Top Mountain
(Robinson et al, 1975; Rowley, et al , 1979).

The thrusting that occurred in the GRA is thought to be related to a period of Ter-
tiary deformation which caused the Precambrian and portions of the Paleozoic sec-
tion to be thrust over younger units. Deformation and thrusting have obscured the
true stratigraphic sequence in much of the GRA. It appears that Tertiary units lie
directly and unconf ormably upon the exposed Precambrian, Paleozoic and Mesozoic
sections (Rowley et al, 1979; Robinson et al, 1975; Heylmun, Personal Communica-
tion, 1982; Carpenter, Personal Communication, 1982).

Mineral resources that are thought to be of economic significance have been found
in the Douglas Mountain area (See Overlay B) . Mineralization consists of copper-
silver-iron-lead-zinc mineralization associated with faults in the Mississippian
Humbug Formation (Rowley et al , 1979; Robinson et al , 197 5; Carpenter, Personal
Communication, 1982; Gilmour, Personal Communication, 1982). Some of these faults
may have localized the mineralization and caused some enrichment of values (Gil-
mour, Personal Communication, 1982; Carpenter, Personal Communication, 1982).

The following descriptions address the structural and tectonic characteristics of
each of the individual WSA's within the Bull Canyon/Dinosaur National Monument
Adjacent-North GRA.

BULL CANYON WSA (CO-010-001/UT-080-419)

Structural features found within the WSA include northeast striking high angle
joint systems, the westward extension of the Blue Mountain (Willow Creek) anticlin-
al structure, and a portion of a mapped low angle thrust plate. Deformation and
thrusting have obscured the true stratigraphic sequence within the WSA. No known
unconformities are thought to exist within the WSA.

DINOSAUR ADJACENT-NORTH WSA'S (CO-010-224, 224A, 226, 228, 229D)

Structural features found within the WSA units Include high angle, east-northeast
striking fault and joint systems that may localize copper-silver-iron-lead-zinc

II-4

mineralization or have caused significant enrichment of values within these depos-
its (Gilmour, Personal Communication, 1982; Carpenter, Personal Communication,
1982). The areas lie on the southern flank, of the Browns Park Syncline. Minor
fault and joint systems that parallel the trace of the axial plane of the Browns
Park Anticline cut through the area and have a west-northwest orientation. These
may be a factor in localization of oil, gas, and copper-silver-iron-lead-zinc
deposits within the WSA's and in adjacent areas (Gilmour, Personal Communication,
1982; Heylmun, Personal Communication, 1982).

Deformation has obscured the true stratigraphic sequence within the WSA's but it
appears from the evidence at hand that there are no major unconformities within the
areas. Within the stratigraphic section, the entire Ordovician-Devonian strata is
missing, representing a probable unconformity. Locally, the Tertiary Browns Park
Formation and the Bishop Conglomerate overlie portions of the Precambrian and Pale-
ozoic sections that were exposed in Tertiary time (Rowley et al, 1979). The Browns
Park Formation is known as a past producer of uranium (Robinson et al , 197 5), and
may have deposits associated with the basal conglomerate that unconformably over-
lies the Precambrian Uinta Formation in unit 228 (Carpenter, Personal Communica-
tion, 1982).

PALEONTOLOGY

Paleontological resources in the GRA are known from past studies of the oil, gas,
and mineral potential of the region. In addition, specific studies of the paleon-
tological resource potential of Dinosaur National Monument (Sears, 1962; Unterman
et al, 1954; NPS File Data, 1982), and the general stratigraphy of the area were
carried out by Federal, state and local governments and oil companies (Sears, 1962;
Unterman et al, 1954; Robinson et al, 197 5; NPS File Data, 1982; Rowley et al ,
1979).

Within the boundaries of the GRA, the Cambrian Lodore Formation is known to contain
trilobite, brachiopod, gastropod and marine plant fossils (Unterman et al , 1954).

The Mississippian Madison and Deseret Formations are also known to have fossilifer-
ous units that contain coral, brachiopod, gastropod and crinoid remains (Unterman
et al, 1954; NPS File Data, 1982). The Pennsylvanian Morgan and Round Valley
Limestone Formations are also known to contain fossil bryozoa, crinoid, sponge,
echinoderm, brachiopod and foraminifera material, and may contain algal reef
material (Unterman et al, 1954; Rowley et al, 1979). Other fossiliferous units
have been reported from the Permian Park City Formation. These units contain
oolites and other fossil material, and have been mined in other areas of western
United States for the phosphate content (Unterman et al , 1954; Rowley et al ,
1979).

The Triassic section that is exposed within the GRA is known to contain fossil
material and reptile tracks. The Moenkopi Formation is a well known locality for
fossil reptile tracks in Arizona, Utah and Western Colorado (Unterman et al , 1954;
NPS File Data). The overlying Chinle Formation is known to contain amphibian,
reptile, and coprolite material. Within the GRA and in other areas of Colorado,
Utah and Arizona, petrified wood is associated with this unit and the basal Shina-
rump Conglomerate (Unterman et al, 1954; NPS File Data, 1982).

II-5

The Jurassic Carmel, Curtis and Morrison Formations are known fossil localities
within the GRA (Unterman et al , 1954; NPS File Data; Rowley et al, 1979). Pelecy-
pods and gastropods have been identified from the Carmel Formation in areas west of
the GRA. (Unterman et al, 1954). The Curtis Formation contains fossiliferous
units which contain saurian, reptile, gastropod, oyster, and belemite remains
(Unterman et al, 1954; NPS File Data, 1982). The Morrison Formation contains the
most significant fossil resource known to exist within the GRA. The paleontologi-
cal remains may include saurian reptile, bird, and mammal remains (Unterman et al,
1954; NPS File Data, 1982). Over 150 species of fossil material have been identi-
fied from this unit (NPS File Data, 1982).

The Cretaceous section also contains several units that contain fossil material
within the GRA. Plant impressions and fossil plant material has been noted in the
Dakota Sandstone in association with coal seams and carbonaceous shale units (NPS
File Data, 1982; Unterman et al, 19 54; Rowley et al , 1979). The Mowry Shale Member
of the Mancos Shale is also reported to contain abundant fish scales (NPS File
Data, 1982; Rowley et al, 1979). Plant fossils, sharks teeth, oyster shells, and
brachiopods are commonly found in certain beds of the Frontier Formation of the
Mancos Shale (Unterman et al, 1979; NPS File Data, 1982). Marine fishes and
mollusks are also commonly associated with the Upper Cretaceous Mancos Shale and
Mesaverde Group units (NPS File Data, 1982). Carbonaceous material and fossil
plant remains have been identified from both of these units in association with
coal seams (NPS File Data, 1982).

Tertiary units that are known to contain mammal fossils are the Bishop Conglomerate
Formation and the Browns Park Formation. Early mammal remains have been recovered
from these units and the Uinta Formation in areas outside of the GRA.

The following addresses the paleontology of each of the WSA's in the Bull Canyon-
Dinosaur National Monument Adjacent-North GRA.

BULL CANYON WSA (C0-010-001/UT-080-419)

The Jurassic and Cretaceous rock units that outcrop within this area are not known
to contain paleontological resources of major scientific importance (NPS File
Data, 1982). The Jurassic Morrison is well known for reptile, bird and mammal
fossil material. Reported major fossil occurrences within this unit are found a
short distance away in Dinosaur National Monument (NPS File Data, 1982).

The Cretaceous Frontier and Dakota Sandstone Formations crop out along the southern
portion of the WSA, and may contain fossil plant and marine fish remains (NPS File
Data, 1982). Saurian reptile remains have been tentatively identified in the
Cretaceous Cedar Mountain Formation. This occurrence is some distance away from
the WSA in Dinosaur National Monument (NPS File Data, 1982).

DINOSAUR ADJACENT-NORTH WSA'S (CO-010-224, 224A, 226, 228, 229D)

Within these areas the Cambrian, Mississippian, Pennsylvanian and Permian units are
not known to contain paleontological resources of major scientific importance (NPS
File Data, 1982). The Cambrian Lodore Formation contains a few fossils in the
Douglas Mountain Area (Units 010-226 & 228) (NPS File Data, 1982), that are useful
for correlation of this unit. These remains (brachiopods and trilobite pieces) are
not considered of particular scientific interest as there are other, better

II-6

localities for this faunal assemblage (NPS File Data, 1982; Carpenter, Personal
Communication 1982). The Mississippian Humbug and Madison Limestone Formations are
thought to be fossiliferous within one or more of the units under study but have
not been extensively studied (NPS File Data, 1982; Unterman et al, 1954). The
Pennsylvanian Morgan Formation units that crop out in unit 229D are also reported
to contain fossil material (Bryozoans, crinoids brachiopods and echinoderms) that
is not well preserved (NPS File Data, 1982).

There are no reported fossil localities within the Mesozoic and Tertiary sections
that are exposed within the various WSA's.

Potential for paleontological resources of major scientific interest is thus limi-
ted to the few outcrops of the Tertiary Browns Park. Formation that are found in
unit 229D. These units may contain early mammal remains and, thus, may be quite
important (NPS File Data, 1982).

HISTORICAL GEOLOGY

During middle and younger Precarabrian time the entire GRA was receiving sediments
from both cratonic and island arc sources (Gilmour, Personal Communication, 1982).
It appears that this was a time of persistent volcanisra and tectonic activity.
Marine deposition of eugeosynclinal sediments was interrupted by the ebb and flow
of cratonic and island arc volcanism, and a period of extreme deformation was
caused by plate collisions and regional uplifting. These older Precambrian units
were metamorphosed, deformed, and intruded by a series of younger Precambrian mafic
and felsic bodies. In this study area, the exposed older Precambrian rocks are
mainly quartzites interbedded with gneiss and schist material. Base and precious
metal deposit types known as exhalative deposits, are commonly found in Precambrian
lithologies. These exhalative deposits, found in association with marine basins
and rhyolitic volcanic systems, and are commonly associated with the older Precam-
brian lithologies.

The Precambrian sequence is relatively unstudied in this areas and has only been
partially correlated with other areas of Colorado (Unterman et al, 1954). In this
area, the younger Precambrian is preserved, and consists of a thick section of
clastic sediments. These lithologies represent a period of clastic deposition in a
marine environment. From the information that is currently available, it appears
that the younger Precambrian units of this area were deposited in a deep, marine
basin that persisted through Paleozoic time (Unterman et al , 1954).

The period of early and middle Paleozoic deposition was characterized by the forma-
tion of a series of shallow basins. It is thought that these basins were progres-
sively filled by Cambrian and Mississippian sediments (Unterman et al, 1954).

During most of the Paleozoic, the basins teemed with plant and animal life. Reef
communities were formed on shallow bedrock highs in association with algal bio-
herms. Northwest striking faults and shear systems were active within the basins,
and caused much up and down movement of the basement blocks that formed the floor
of these basins.

In the Mesozoic, the area was the site of fluvial and lacustrine deposition in a
terrestrial environment. The Triassic Moenkopi Formation overlies the Paleozoic
units throughout much of the GRA, and is thought to represent an era when shallow,

II-7

fresh water lake and enclosed basins were subjected to periods of desslcation and
shallow water, clastic deposition. The Moenkopi Formation is known for its saurian
tracks and vertebrate fossils in other areas of western Colorado. Thus, it is
reasonable to assume the amphibian and reptile life may have existed within the GRA
during this period (NPS File Data, 1982). The Chinle Formation of the Glen Canyon
Group represents a time of Triassic sedimentation in a near-shore environment with
episodes of eolian deposition of well cross-bedded beach and dune sand deposits.

Certain fluvial and shallow water lacustrine deposits have also been identified in
this sequence of sandstone, shale, siltstone, mudstone, limestone and conglomerate.
It appears that the Triassic units were deposited along the margins of great, open
seas and restricted inland basins that had existed since Paleozoic time. As the
shorelines of these seas moved in response to orogenic episodes and basin fillings,
the specific environments in the GRA changed from marine to terrestrial. During
this time, shallow-water and near shore swamps were formed. In other areas of
Colorado, these Upper Triassic near-shore sediments are the host for copper-silver
"redbed" deposits that were deposited in areas of rapidly changing Eh-pH condi-
tions .

The Navajo Sandstone outcrops in the western portion of the GRA and is thought to
represent a period of inland sand dune accumulation in a terrestrial desert envi-
ronment (Carter et al, 1965). This Triassic- Jurassic unit thins to the east.

The unconformity between the Navajo Sandstone and the overlying Jurassic Carmel and
Entrada Formations is probably a local feature that represents a period of non-
deposition. The Navajo is known to exist only in selected, desert environments or
basins, and may have never been deposited in some areas. The Jurassic Entrada,
however, is thought to have been deposited during a period of terrestrial fluvial
and eolian deposition in small, restricted basins that eventually coalesced and
buried the majority of the resistant Precambrian Highland features. The Jurassic
Summerville and Morrison Formations were being deposited in near-shore lagoonal
environments, or shallow water marine and fluvial systems. Some fresh water lacu-
strine and fresh water fluvial deposits have also been identified from these rocks.
As in the earlier Triassic section, mineral deposits are commonly found associated
with limey sandstones, shales, and siltstones, deposited in shallow, neritic basins
that have fluvial channels meandering through them. Fossil plant material from
this period is indicative of a tropical environment that was adjacent to an active
fluvial or lacustrine system.

During Cretaceous time, the GRA was the site of shallow water deposition in a
lagoonal or swamp environment. The Lower Cretaceous Burro Canyon Formation appears
to have been deposited in a series of meandering river systems with adjacent ter-
restrial lakes. The terrestrial, clastic nature of this formation is thought to be
characteristic of a beach or littoral environment (Young, 1955). The Upper Creta-
ceous Dakota Sandstone unconformably overlies the Burro Canyon Formation. Clastic
portions of the Dakota are found as channel fillings in the Burro Canyon paleosur-
face. From fossil evidence, it appears that the lower sections of the Dakota were
deposited in shallow basins or stream channels. The carbonaceous shales of the
Dakota are known to contain abundant plant remains, and were probably deposited in
a near-shore swamp or lacustrine environment. Thin coal seams are known to exist
within the Dakota and may have economic potential.

II-8

During upper Cretaceous time, the thickest marine deposition occurred to the south-
east and spread westward grading laterally into coarser sediments derived from the
west and which are thought to signify the initial impulses of the "Early Laramide"
deformation in the Uinta Range.

This deformation of the region brought about a gradual downwarping of the Uinta and
Bridger Basins with a consequent development of small lakes and ponds which in time
became extensive fresh-water bodies into which accumulated thousands of feet of
fine sediment, now believed to be a source of some of the oil of the region. As
deformation abated, the lake basins were gradually filled by the streams, eventual-
ly creating extensive flood plains on which additional thousands of feed of con-
glomerate, sandstone and shale accumulated (Bridger, Washakie and Uinta, Eocene;
and Duchesne River, Oligocene) which have been the source of vast quantities of
fossil material, including mammal, reptile, insect and plant remains.

Units of the Cretaceous Mancos Shale have been described as being sandstone and
shale units deposited in a near-shore environment, and have local coal bearing
horizons in the section.

The Cretaceous Mesaverde Group units crop out throughout the northeastern portions
of the GRA and represent a period of cyclical deposition of shale, coal, limestone
units in a near-shore marine environment adjacent to the deep-water basins where
the bulk of the Mancos Shale unit was deposited. Coal bearing units of the Mesa-
verde Group are found in the lower portions of the Williams Fork and lies Forma-
tions and are considered a major energy resource (Vanderwilt, 1947).

The Mesaverde Group is overlain by the Tertiary Wasatch, Uinta, Green River and
Browns Park Formations. This unconformity may represent a period of uplift and
erosion prior to the formation of the Uinta sedimentary basin. The Wasatch, Uinta,
and Green River Formations found in the GRA represent periods of shallow water ter-
restrial lacustrine deposition. These units intertongue and contain known oil
shale resources. The shallow water basins existed to the east of the GRA on the
flank of the Uinta Arch. The Tertiary Brown's Park Formation was deposited in a
series of structural basins that formed adjacent to the Uinta Arch and along it's
axis. These reworked, volcanic and sedimentary units locally contain uranium-
vanadium deposits (Nelson-Moore et al, 1979). The Bishop conglomerate also crops
out within the GRA and is thought to represent eroded material from the exposed
Precambrian and Paleozoic units.

The area was uplifted and subjected to erosion in Middle Tertiary times with the
formation of the ancestral Green River Valley. Quaternary pediment, Terrace gravel
and eolian deposits formed on the exposed Precambrian-Tertiary surfaces and alluvi-
al deposits were formed along the various fluvial systems that were established.

BULL CANYON WSA (CO-010-001/UT-08O-419)

Little information is available that directly pertains to the historical geology of
the WSA. Within the boundaries of the WSA, the Upper Jurassic and Lower Cretaceous
section crops out as a folded sequence of shale, siltstone, and sandstone units.
The entire Precambrian-Lower Jurassic stratigraphy is thought to underlie the WSA,
but does not crops out in the nearby vicinity. The units that crop out have been
uplifted and eroded since the Laramide Orogeny. Quaternary alluvial material
directly overlies the outcropping Mesozoic stratigraphy (Rowley et al , 1976).

II-9

DINOSAUR ADJACENT-NORTH WSA'S (CO-010-224, 224A, 226, 228, 229D)

Within these areas the Cambrian Lodore Formation directly overlies the Uinta Moun-
tain Group sedimentary sequence of shales, sandstone, quartzite and gneiss. It is
thought that the Uinta Mountain Group underlies all of the units of the WSA and was
laid down in a marine environment. The Lodore Formation consists of sandstone,
quartzite, shale and siltstone units that are thought to have been deposited in
off-shore marine environment (Unterman et al, 1954; Rowley et al, 1976). The
Lodore and the overlying Mississippian Madison Formation are known to contain lead,
zinc, iron, copper, gold and silver deposits within various units of the WSA and in
adjacent areas. The nature of this mineralization suggests a structural control
within a series of favorable host lithologies (Gilmour, Personal Communication,
1982; Carpenter, Personal Communication, 1982). The Madison Formation lies direct-
ly and conformably upon the Lodore and it is thought that the Ordovician, Silurian
and Devonian units that are found in other areas of western United States were
never deposited in this portion of Colorado (Unterman et al, 1954). Within the
boundaries of most of the units of the WSA, the Madison Formation is a dense, fine-
grained limestone that is thought to be of marine origin. During Lower Paleozoic
time the area of the WSA was a part of a major marine basin and contained abundant
marine life.

Cropping out in adjacent areas of Dinosaur National Monument is the Mississippian
Deseret Limestone Formation. This unit consists of a series of fossiliferous lime-
stone and dolomite units and is thought to be of marine origin (Unterman et al,
1954). This unit and the overlying Mississippian Humbug Formation may represent
favorable host lithologies for base and precious metal mineralization similar to
what has been found in the Lodore and Madison Formations (Gilmour, Personal Com-
munication, 1982; Carpenter, Personal Communication, 1982).

All of the Lower and Middle Paleozoic units that crop out within the units of the
WSA are thought to have been deposited in a marine environment. It is thought that
a complete sequence of post-Mississippian lithologies was deposited within the
areas of the WSA, and that these units were uplifted and eroded during the Laramide
Orogeny. Currently, in most of the units of the WSA the Precambrian-Mississippian
section is all that outcrops. In unit 229 the Tertiary Browns Park Formation was
deposited in a local basin after tectonism an erosion had taken place. Unlike
other areas of Colorado, this Formation does not have any reported occurrences of
uranium-vanadium mineralization (Nelson-Moore et al, 1979; Unterman et al, 1982).

Directly overlying all of the exposed stratigraphy are a series of eolian and
alluvial deposits of Quaternary age (Rowley et al, 1976).

Figures II-l through II-6 illustrate the geology and geomorphology of the GRA.

11-10

DINOSAUR NATIONAL MONUMENT

FIGURE 11-1
Looking N.
Note ranch trails.

FIGURE II-2

Madison (?)

limestone

in foreground.

Cambrian (?)

quartzite in middle.

-^ft

DINOSAUR NATIONAL MONUMENT

ii-n

.*f~

FIGURE H-3

Photo looking S, Douglas
Mountain mine. Mineralization at
or near contact between quartzite

(in foreground), and carbonates above.

DINOSAUR NATIONAL MONUMENT

FIGURE 11-4

Douglas Mountain

mine from S.

(Looking NNE).

Limestone outlier

overlying quartzite.

_^ ,,, £(/&m&B&W$$lk:.

■■■* ;^^^^

ty,.£fc

* • -

* * «. t
* *■- zf v* *^.

•

•• ♦ . lb* ■

DINOSAUR NATIONAL MONUMENT

11-12

L**

FIGURE 11-5
Prospect
(labeled mmine"
on 1:24,000 topo
sheet) located to SE
of Douglas Mountain
mine. Mineralization
associated with
contact between
limestone "cap" and
underlying quartzite.

DINOSAUR NATIONAL MONUMENT

FIGURE II— 6

"Mine" in
foreground: Douglas

Mountain mine in
back (looking NW).

DINOSAUR NATIONAL MONUMENT

11-13

SECTION III
ENERGY AND MINERAL RESOURCES

KNOWN MINERAL DEPOSITS

The known deposits in the Bull Canyon/Dinosaur National Monument Adjacent-North
GRA can be grouped into three categories: 1) energy minerals; 2) metals; and
3) sand, gravel and industrial minerals. The following summarizes the known
deposits:

Commodity

Number of Deposits

Coal mines 2

Uranium mines 2

Copper-iron-zinc mines 2

Copper- lead-zinc mines 2

Iron with assoc. silver mines 2

Sand and gravel pits 13

Clay pits 2

Sandstone quarries 3

Coal has been produced from the Blue Flame and Les Ash mines which are located in
the extreme northern portion of the Lower White River Coal Field in T3N, R102W
(Overlay C).

The three known uranium mines in the GRA are the Skull Creek Coalition Mines Blue
Mtn. No. 4, Skull Creek mine and Biles' Shaft, located in T4N, R100 and 101W (Over-
lay B) . The current operating status of the Blue Mtn. No. 4 and Skull Creek mine
is unknown. The Biles' Shaft, however, has been abandoned.

The base metal mines are located in T7N, R101W in the Douglas Mountain District
(Overlay B) . The primary commodities produced were copper and iron.

The sand, gravel and industrial mineral deposits are located in the southwestern
and southern portion of the GRA (Overlay D) .

BULL CANYON WSA (CO-01O-001/UT-08O-419)

There are no known deposits in the Bull Canyon WSA.

DINOSAUR ADJACENT-NORTH WSA'S (CO-010-224, 224A, 226, 228 & 229D)

In block CO-010-226 of the Dinosaur National Monument WSA, there are two copper
mines located in sections 15 and 16, T7N, R101W (Appendix A, topographic maps).
The Bromide shaft is located at the northern edge of block CO-010-226 in section 9,
T7N, R101W. The Bromide mine appears to have been worked intermittently over a
considerable period of time (Appendix A, field notes).

III-l

KNOWN PROSPECTS, MINERAL OCCURRENCES AND MINERALIZED AREAS

The following table summarizes the known prospects and mineral occurrences in the
Bull Canyon/Dinosaur National Monument Adjacent-North GRA:

Commodity

Number of Prospects or Occurrences

Oil and gas dry wells

Coal

Uranium

Manganese

Copper

Copper, Manganese, Lead, Zinc

Copper, Iron, Zinc

Iron

Petrified Wood

6 prospects

8 occurrences
5 occurrences
5 occurrences
3 occurrences

9 occurrences
12 occurrences
1 occurrence

The coal, oil and gas prospects are located in the southwestern portion of the GRA
in T5 and 6S, R25E (Overlay C) .

The manganese occurrences are all located in T5N, R99W in the east central portion
of the GRA. One uranium occurrence is found in the vicinity of the manganese
occurrences, however, uranium occurrences are primarily found in the Skull Creek
Area in T4N, R101W.

The base metal occurrences are noted in the Douglas Mountain District and the Skull
Creek Area in the north central and south central portion of the GRA, respectively
(Overlay B) .

Copper mineralization, noted in the field, was found in the Douglas Mountain Dis-
trict and vicinity (Appendix A, field notes).

Vertebrate paleo remains occur in the Browns Park Formation.

BULL CANYON WSA (CO-010-001/UT-080-419)

There are no known prospects, mineral occurrences or mineralized areas in the Bull
Canyon WSA.

DINOSAUR ADJACENT-NORTH WSA'S (CO-010-224, 224A, 226, 228, 229D)

There are no known prospects in the Dinosaur Adjacent-North WSA's; however, there
are several known occurrences.

The CO-010-224 block contains 7 known iron occurrences located in sections 9, 16
and 21, T7N, R102W (Overlay B) . The CO-010-226 block contains known copper occur-
rences in sections 16, 17 and 18, T7N, R101W. In addition to these occurrences,
copper mineralization was observed in the field along a northwest trending fault
zone in the vicinity of the Bromide shaft in section 16, T7N, R101 (Appendix A,
field notes).

III-2

MINING CLAIMS, LEASES AND MATERIAL SITES

There are 7 05 unpatented lode claims and 1 unpatented placer claim in this GRA, of
which 53 lode claims are within the WSA's (Overlay A). The claims are primarily
situated in the extreme northern and southern portion of the GRA. Two major cor-
porations, Molycorp and Gulf Oil Company, hold claims in the GRA. The unpatented
claim data was compiled from the Bureau of Land Management's June 14, 1982, Geo-
graphic Index (Appendix C).

There are 8 patented mining claims located in the GRA, specifically in sections 5
and 8, T7N, R102W; section 16, T7N, R101W; sections 15, 22 and 23, T7N, R101W; and
sections 23 and 24, T7N, R101W (Overlay A and Master Title Plats, Appendix A).
This information was obtained from the BLM's Surface Management Quads and Master
Title Plats.

Data on leases was not obtained for the entire GRA. Please refer to the Oil and
Gas Plats in Appendix A.

BULL CANYON WSA (CO-010-001/UT-080-419 )

As of June 14, 1982, there were no patented or unpatented mining claims contained
with the WSA.

Data on oil and gas leases was not available for the Bull Canyon WSA.

DINOSAUR ADJACENT NORTH WSA'S (CO-010-224, 224A, 226, 228, 229D)

There are approximately 53 unpatented lode mining claims located within the five
WSA's (Overlay A). Specifically, there are 15 lode claims located in CO-010-224, 6
lode claims in CO-010-224A, 9 lode claims in CO-010-226, no claims in CO-010-228
and 23 lode in CO-010-229D. The unpatented claim data was compiled from the Bureau
of Land Management's June 14, 1982, Geographic Index (Appendix C). An exact number
of mining claims located within the WSA's cannot be derived from the Geographic
Index since claims are only located to within a quarter-section. However, an exact
number of claims can be obtained through researching the claim location notices
recorded with the BLM by the claimant.

There are two patented mining claims located in WSA CO-010-226, section 16, T7N
R101W (Overlay A). The patented claim data was obtained from the BLM's Surface
Management Quads and Master Title Plats (Appendix A).

For information on oil and gas leases, please refer to the oil and gas plats in
Appendix A.

MINERAL DEPOSIT TYPES

The Bull Canyon/Dinosaur National Monument Adjacent-North GRA contains known depos-
its of coal, uranium, base and precious metals, construction stone, clay, and sand
and gravels.

III-3

The Lower White River Field contains the known coal deposits in the GRA. Coal for
local use has been mined from the thin discontinuous coal beds in the Dakota Sand-
stone. Coal deposits of economic significance are derived from the Williams Fork.
Formation of the Cretaceous Mesaverde Group (Landis, 1959). The Mesaverde group is
composed of shale, carbonaceous shale, sandstone and coal beds. The coal is ranked
as high-volatile C bituminous and is noncoking (Landis 1959).

The uranium deposits usually occur in the Jurassic Morrison Formation. In the
Morrison Formation carnotite, a uranium and vanadium oxide, is the principal ore
mineral. Carnotite is a secondary mineral deposited by waters that were in contact
with primary uranium and vanadium minerals. Uranium and vanadium mineralization
occurs in the Salt Wash Member and the Brushy Basin Member of the Morrison Forma-
tion. The Salt Wash Member consists of interstratif ied sandstone and claystone
units. The unit was formed as a large alluvial fan by an aggrading system of
braided streams (Craig et al, 19 55). The Brushy Basin Member consists of varie-
gated claystones with few lenticular conglomeratic sandstone strata. The Brushy
Basin was formed in fluvial and lacustrine environments with large amounts of clay
(Craig et al, 1955). As a whole, the sandstone beds of the Morrison Formation are
light gray to buff, fine to medium grained, lenticular, crossbedded and irregularly
bedded (Molenaar, 1981). It is thought the introduction of the ore was done by
mineral-bearing solutions that seeped through the permeable layers after sediments
accumulated. The source of the primary minerals is currently under dispute (Craig
et al, 1955).

The Douglas Mountain district contains replacement deposits of copper, lead, zinc,
iron, manganese and silver. These deposits are found in the Cambrian Lodore Forma-
tion at or near its contact with the Mississippian Madison Formation (Rowley et al ,
1979; Gilmour, Personal Communication, 1982). The Lodore Formation is composed of
a fine grained, silty, fossiliferous quartzitic sandstones, a glauconitic middle
sandstone, and sericitic shale beds (Unterman et al, 195A). The fossiliferous
Madison Formation consists of limestone and dolomite at the base, which is overlain
by cherty marine limestone, dolomite and marlstone beds. The principal ore miner-
als consist of hematite, limonite, malachite and azurite. Lead, zinc, manganese
and silver minerals are found to a lesser extent (Unterman et al, 1954). Minerali-
zation was localized by faulting.

Copper-silver-iron mineralization occurs in the Precambrian Red Creek Quartzite
units in areas to the northwest of the GRA. This mineralization may be syngenetic
and associated with favorable host lithologies.

Clay has been derived from the Mancos Formation, Dakota Sandstone and the Mesaverde
Formation.

Pediment gravels from the Yampa River and its tributaries have been exploited, as a
source of sand and gravel. Sandstone has been quarried in the past. The source
formation of this material is unknown.

BULL CANYON WSA (CC-010-001/UT-080-419)

There are no known mineral deposits in the Bull Canyon WSA, therefore, any descrip-
tion of deposit types would be theoretical.

III-4

DINOSAUR ADJACENT-NORTH WSA'S (CO-OlO-224, 224A, 226, 228, 229D)

There are two known copper deposits In unit CO-010-226. These deposits are found
at or near the contact of the Cambrian Lodore Formation and the Mississippian Madi-
son Formation. Please refer to the aforementioned description on copper deposit
type.

MINERAL ECONOMICS

The inherent nature of discussing the economics of the minerals existing within the
Bull Canyon/Dinosaur National Monument Adjacent-North GRA and its WSA's can only
provide for a general approach inasmuch as there are many economic factors that
enter into the development of an ore body. These include access, market value,
grade, transportation, recovery and extraction methods, etc. Therefore, the dis-
cussion herein addresses the U.S. and Colorado demand and production status of each
of the existing minerals in the WSA's.

The mineral resources in the GRA include coal, uranium, base and precious metals,
construction stone, clay, and sand and gravel.

Coal is found in the Lower White River Field. There are two coal mines and six
prospects of which the operating status and production are not known. Coal produc-
tion for Colorado mines is currently at an all time high. Approximately 20,000,000
tons of high-grade low-sulphur coal was produced from surface mines and underground
operations (Colo. Div. Mines Rept., 1980; and Schwochow, 1978). The future looks
encouraging for coal as more and more utilities are switching back to coal for pow-
er generation (Schowochow, 1978; Colo. Div. Mines Rept., 1980). Changes in tech-
nology and improvements in combustion/distillation techniques will increase the
demand for Colorado coal, and coal byproducts (Gentry, Personal Communication,
1982).

The uranium deposits occur in the Jurassic Morrison Formation. Three uranium
mines, and eight occurrences are found in the GRA. One mine has been abandoned,
and the operating status of the other two is not known. In addition, production
statistics from all three are not known. Current production is down from past pro-
duction levels due to a general drop in the price of uranium (Eng. and Mining Jour-
nal, Dec, 1982). Uranium and vanadium are currently being produced at very little
or no profit by many of the major mining operations in Colorado (Carpenter, Person-
al Communication, 1982). Future demand for uranium and vanadium is dependent on
foreign production and the needs of the nuclear generating industry (Schwochow,
1978).

Base and precious metals in the form of copper, lead, zinc, iron, manganese and
silver occur as replacement deposits in Cambrian formations. Currently, a strong
demand for precious metals exists in the U.S. and Colorado. Production and demand
for base metals, however, is down from past levels due to a general down- turn in
the U.S. and world economy (Eng. and Mining Journal, Dec. 1982). Commodities such
as copper, lead, zinc, manganese, and iron are not being currently produced at a
substantial profit by any of the major mining operations in Colorado (Eng. and Min-
ing Journal, DEc 1982; Carpenter, Personal Communication, 1982).

III-5

Construction stone, common clay, and sand and gravel are considered "high place
value" industrial minerals. These minerals are of economic value only when the
deposits are readily accessible, and in close proximity to a market.

The economic viability of the mineral resources in the WSA's in the Bull Canyon-
Dinosaur National Monument Adjacent-North GRA are summarized as follows:

WSA MINERAL POTENTIAL ACCESSIBILITY ECONOMIC POTENTIAL [a]

Bull Canyon This WSA has no known mineral/economic potential.
(UT-080-419)

Poor

Good

Poor

*No known deposits or occurrences in WSA. Refer to Section IV for explanation of
the economic potential.

[a] The economic potential rating is notwithstanding market demand fluctuations.

Dinosaur

Oil, Gas

Poor

Adjacent-

North WSA

Base Metals

Good

(CO-010

224, 224A,

Uranium &

Poor

226, 228,

229D)

Precious Metals*

Poor

III-6

SECTION IV
LAND CLASSIFICATION FOR GEM RESOURCES POTENTIAL

After thoroughly reviewing the existing literature and data base sources, MSME/
Wallaby personnel plotted all known and documented mineral occurrences, mines,
prospects, oil and gas fields, sand and gravel operations, processing facilities,
mining claims, mineral leases, and the locations of anomalous geochemical samples
from the National Uranium Resource Evaluation-Hydrological and Stream Sediment
Reconnaisance-Airborne Radiometric and Magnetic (NURE-HSSR-ARMS) programs. This
plotted information and the data bases on each WSA were made available to a multi-
faceted team of experts which made three successive evaluations of the GEM resource
potential of each of the WSA's.

The team or panel of geological experts was comprised of:

Dr. Paul Gilmour: Base and precious metal deposits in western U.S. and Canada,
expert on Precambrian mineral resources.

Mr. Ted Eyde: Base and precious metal deposits in western U.S., expert on indus-
trial mineral resources.

Mr. Annan Cook: Base and precious metal deposits in western U.S., expert on
porphyry deposits and mine evaluation.

Mr. Edward Heylmun: Oil, gas and oil shale deposits of western U.S.

Dr. Robert Carpenter: Mineral deposits of Colorado and western U.S., expert on
geology of Colorado.

Dr. Donald Gentry: Expert in coal and oil shale deposits of Colorado and western
U.S.

Dr. Larry Lepley: Expert in remote sensing and geothermal resources;

Mr. Walter E. Heinrichs: Geophysics and base and precious metal deposits of west-
ern U.S., expert on porphyry copper deposits.

As indicated earlier, Dr. Gentry, and Carpenter made certain field investigations as
result of the base data analysis phase. The purpose of the field investigations
was to either verify the existing data or assess relatively unknown areas. Dr.
Lepley reviewed all aerial photographs for observable anomalies, which were then
investigated by the field team, or verified against the existing base data.

The evaluations were then made on the basis of examination of the data bases, field
investigations and the individual experiences of the members of the panel in such
areas as base and precious metal, industrial and energy mineral deposits; oil and
gas deposits; and geothermal resources. In the course of these evaluations, every
attempt was made to objectively rate the potential for a particular commodity with-
in the respective study area. In this effort, the evaluation criteria proposed by
the Bureau was rigorously used. The classification scheme used is shown in Table
IV-1. In many cases the lack of information did not allow for a full determination

IV-1

TABLE IV- 1
RESOURCE RATING CRITERIA

CLASSIFICATION SCHEME

1. The geologic environment and the inferred geologic processes do not indicate
favorability for accumulation of mineral resources.

2. The geologic environment and the inferred geologic processes indicate low
favorability for accumulation of mineral resources.

3. The geologic environment, the inferred geologic processes, and the reported
mineral occurrences indicate moderate favorability for accumulation of mineral
resources .

4. The geologic environment, the inferred geologic processes, the reported mineral
occurrences, and the known mines or deposits indicate high favorability for
accumulation of mineral resources.

LEVEL OF CONFIDENCE SCHEME

A. The available data are either insufficient and/or cannot be considered as
direct evidence to support or refute the possible existence of mineral
resources within the respective area.

B. The available data provide indirect evidence to support or refute the possible
existence of mineral resources.

C. The available data provide direct evidence, but are quantitatively minimal to
support or refute the possible existence of mineral resources.

D. The available data provide abundant direct and indirect evidence in support or
refute the possible existence of mineral resource.

IV-2

of the GEM resource potential and the panel was forced to leave some areas unranked
or classified for some commodities. The situation thus arises where there is an
area that has been unclassified for a commodity, despite a reported occurrence,
because it is next to an area where there is insufficient data to make a meaningful
attempt at classification. Nonetheless, each resource has been additionally rated
as to what level of confidence the panel of experts attached to the selected
classification level. This is denoted by the letter associated with each rate
classification. These are defined in Table IV-1.

A further restraint on this classification and delineation effort comes in the area
of the lack of subsurface information. Some areas are very well known from past
exploration efforts and have an abundance of subsurface information. Other areas
are practically unknown due to an absence of any past exploration or development
efforts .

The WSA's, for the most part, are not well known geologically. For this reason,
our expert team had to extrapolate geologic information from adjacent areas to make
any sort of reasonable classification with some level of confidence. The following
pages address those resources considered to be leasable, locatable and/or salable
with associated maps locating the resource area (Figures IV-1 through 3):

IV-3

LEASABLE RESOURCES

BULL CANYON WSA (UT-080-419)

Resource

Oil and Gas

Coal

Phosphate

Classification

2B
ID
3B

Comments

The WSA contains a thin Paleozoic section.

Lacks coal-bearing formation.

Permian Phosphoria Formation underlies area

DINOSAUR ADJACENT-NORTH WSA'S (CO-010-224, 22AA, 226, 228, 229D)

Oil and Gas

CO-010-224

CO-010-224A

CO-010-226

CO-010-228

CO-010229D

Coal

CO-010-224

CO-010-224A

CO-010-226

CO-010-228

CO-010-229D

Unknown Precambrian overthrust potential
Unknown Precambrian overthrust potential
Unknown Precambrian overthrust potential
Unknown Precambrian overthrust potential
Cretaceous and Paleozoic section is
present

Coal-bearing formations lacking
Coal-bearing formations lacking
Coal-bearing formations lacking
Coal-bearing formations lacking
Coal-bearing formations lacking

IV-4

CO-010-001

R 25 E

Bull Canyon

R 104 W

R 103 W

Portion of Unit found to lack
Wilderness characteristics

Existing National Park or
Forest Service Wilder nets

: /<v7r~71 Proposed National Park Service
*".°V ■■- 1 or Forest Service Wilderness

5 Miles

(after BLM,1980)
MMS/LEASABLE RESOURCES
Figure IV-la

IV-5

CO 010 218 thru 271/N6B Dinosaur National Monument Adjacent North

R102W R 101 W R100W R 99 W

MMS/ LEASABLE RESOURCES
Figure IV- lb

(After BLM. 1980)

IV-6

LEGEND FOR MINERALS MANAGEMENT SERVICE CLASSIFICATIONS

Defined KGS and/or Coal Leasing Areas

Areas Prospectively Valuable for Sodium or Potassium

Defined Oil Shale Leasing Area

Coal
[PV]
OG[PV]

Areas Identified as Prospectively Valuable for
Coal or Oil, Gas

Coal [NPV]
OG [NPV]

Areas Identified as Not Being Prospectively Valuable
for Coal, or Oil, Gas

IV- 7

LOCATABLE MINERALS

BULL CANYON WSA (UT-080-419)
Resource Classification

Precious Metals
Base Metals

(2A)
(2A)

Locatable Energy Minerals:

(2A)

Other Locatable Minerals:
Unknown

comments

Ag mineral potential associated with
Precambrian Uinta Group units.
Cu mineral potential associated with
Precambrian Uinta Group units.

Uranium-vanadium potential associated with
Precambrian Uinta Group units.

DINOSAUR ADJACENT-NORTH WSA'S (CO-010-224, 224A, 226, 228, 229D)

Precious Metals
CO-010-224

CO-010-224A

CO-0L0-226

Au-Ag mineralization in Mississippian
Madison Formation and Cambrian Lodore
Formation in association with fault
controlled replacement-skarn deposits in
Limestone units. Numerous prospects,
production.

Ag mineralization potential associated with
Precambrian Uinta Mountain Group units.

Ag mineralization potential associated with
Precambrian Uinta Group units.

Ag mineralization potential associated with
Precambrian Uinta Mountain Group units.

IV- 8

DINOSAUR ADJACENT-NORTH WSA'S (CO-010-224, 224A, 226, 228, 229D)
(cont'd)

CO-010-228

CO-010-229D

Ag mineralization potential associated with
Precambrian Uinta Mountain Group units.

Ag mineralization potential associated with
Precambrian Uinta Mountain Group units.
Lack of outcropping section.

Base Metals:
CO-010-224

CO-010-224A

Pb-Zn-Fe-Cu-Mn mineralization in
Mississippian Madison Formation and
Cambrian Lodore Formation in association
with fault controlled replacement skarn
deposits in Limestone units. Numerous
prospects, production.

Cu mineralization potential associated with
Precambrian Uinta Mountain Group units.

IV-9

DINOSAUR ADJACENT-NORTH WSA'S (CO-010-22A, 224A, 226, 228, 229D)
(cont'd)

Resource

CO-010-226

Classification

Comments

Cu mineralization potential associated with
Precambrian Uinta Mountain Group units.

CO-010-228

Cu mineralization potential associated with
Precambrian Uinta Mountain Group units.

CO-010-228

Cu mineralization potential associated with
Precambrian Uinta Mountain Group units.

CO-010-229D

Cu mineralization potential associated with
Precambrian Uinta Mountain Group units.

IV-10

DINOSAUR ADJACENT NORTH-WSA'S (CO-010-224, 224A, 226, 228, 229D)
(cont'd)

Resource
Energy Minerals:
CO-010-224

CO-01O-224A

CO-010-226

C0-0L0-228

C0-010-229D

CO-010-229D

Classification

Comments

Uranium-vanadium potential in Precambrian
Uinta Mountain Group.

Uranium-vanadium potential in Tertiary
Browns Park Formation

Uranium-vanadium potential in Precambrian
Uinta Mountain Group.

Other Locatable Minerals:
Unknown

IV- 11

C0010001

R 25 E

Bull Canyon

R 104 W

R 103 W

Portion of Unit found to lack
Wilderness characteristics

Existing National Park or
Forest Service Wilderness

Proposed National Park Service
or Forest Service Wilderness

5 Miles

LOCATABLE RESOURCES
Figure IV- 2a

(After BLM, 1960)

IV- 12

CO 010 218 thru 271 /N6B Dinosaur National Monument Adjacent North
R 1 02 W R 101 W R100W R99W

M(2B)(Ag)
4(2B) (Cu)
-V(2B)

(After BLM, 1980)

i i i fa

L0CATABLE RESOURCES
Figure IV- 2b

IV- 13

SALABLE RESOURCES

BULL CANYON WSA (UT-080-419)

Resource

Sand and Gravel

Classification

Comments

DINOSAUR ADJACENT-NORTH WSA'S (CO-010-224, 224A, 226, 228, 229D)

Dimension Stone

Cement rock

Mineral Pigments

Favorable formations are found within the
WSA: Precambrian Uinta Quartzite, Marble in
PC, Weber Sandstone, Lodore Limestone, Park
City, Madison Limestone.

Derived from the Ladore Limestone, Park
City, Madison Limestone

Pigment production is from the Madison-
Lodore (?). Mineral pigments have a high
unit value therefore moderate potential.

High Calcium Limestone
Phosphate

4A
3B

Derived from the Madison formation

The Phosphoria Formation is a favorable
host for phosphate deposits

IV- 14

CO010-001

R 25 E

Bull Canyon

R 104 W

R 103 W

Existing National Park or
Forest Service Wilderness

Proposed National Park Service
or Forest Service Wilderness

5 Miles

SALABLE RESOURCES
Figure IV- 3a

(After BLM, 1980)

IV-15

CO 010 218 thru -271 /N6B Dinosaur National Monument Adjacent North
RJ02W R 101 W R 100 W R 99 W

(After BLM. 1980)

h i t i '

SALABLE RESOURCES
Figure TV-3b

IV- 16

SECTION V
RECOMMENDATIONS FOR FURTHER STUDY

In the course of analyzing, assessing and evaluating each of the WSA's in the Bull
Canyon/Dinosaur National Monument Adjacent-North GRA - both in the field and in
available data - certain unknowns were uncovered that should be investigated in
order that each WSA's GEM resources be more fully documented. This section
recommends the type of studies and data gathering that should be made to inventory
more completely each WSA.

Since this area is known to have minor potential for oil and gas resources, it is
recommended that every effort be made to ascertain the full extent of this poten-
tial. Cooperative agreements should be made with various oil and gas producers to
obtain proprietary information not available to this study. Such information as
the projected reserves of the area, the importance of structural zones in localiz-
ing oil and gas oils, and the exact identification of pay zones within the general-
ly favorable Hthologies is of vital importance in the exact areal delineation of
sub-surface potential.

In addition, a detailed program of geologic mapping and sampling should be carried
out to fully delineate the extent of the coal bearing horizons in the Cretaceous
section. Any sampling carried out under such a program must include analysis of
the coal material for the ash and sulphur content as well as Btu content. Much
work has already been done on lithofacies reconstruction in the Cretaceous in adja-
cent areas. Studies of this nature would be useful in determining the probable
extent of the coal measures and thus, the viability of the coal as a minable
resource .

The outcrops of the Jurassic Morrison Formation should be sampled for their
uranium-vanadium content, and correlated to other units in northwestern Colorado
and eastern Utah. Examination of the Morrison units should be made by paleontolo-
gists for environments favorable for the preservation of vertebrate remains.

From the work to date and the material compiled in the course of ths project, it
appears that this area has significant potential for GEM resources.

DINOSAUR ADJACENT-NORTH WSA'S (CO-010-224, 224A, 226, 228, 229D)

In this area the potential for GEM resources is largely unknown. Detailed geologic
and geochemical studies are warranted to ascertain the mineral potential of the
Precambrian and Paleozoic Hthologies. Special attention should be paid to possi-
ble sedimentary lithologic assemblages associated with Precambrian base and pre-
cious metal systems. Of equal importance is the potential for base metal minerali-
zation in the Cambrian Lodore and Mississippian Madison Formations. Stratigraphic
and lithofacies mapping should be carried out to determine if any environments with
characteristics exist. A relatively low-cost way to accomplish these goals is to
conduct a stream sediment and outcrop sampling program in conjunction with a geo-
logic mapping effort.

V-l

All existing mines, prospects and known mineral occurrences should be mapped and
thoroughly sampled to delineate the full extent of the existing mineralization and
the potential of the host lithologies. This is of particular importance In the
determination of the copper, lead, zinc, gold, silver, manganese, and iron poten-
tial of the Mississippian Madison Formation and the underlying Cambrian Lodore For-
mation. With regard to these specific units, a detailed study should be made of
fades changes within these units, and the correlations with other units in western
Colorado and eastern Utah. In other areas of Utah, these units have significant
potential GEM resources and thus, should be studied in those areas where there is
available information. Though the airborne and ground NURE-HSSR-ARMS information
does not delineate any areas with anomalous base or precious metal values, ground
radiometrics in conjunction with the geological-geocheraical studies would be help-
ful in identifying any areas of mineral potential.

Stream sediment samples should be analyzed for their copper, molybdenum, lead,
arsenic, uranium, vanadium and gold content. This data will supplement the exist-
ing NURE-HSSR information.

Since some of the Precarabrian units have been used in the past as a source of local
road building and dimension stone material, it would be wise to do further work on
the demand for this material.

In conclusion, from the work to date and the material compiled in the course of
this project, it appears that the potential for GEM resources in this area is
largely unknown.

V-2

SECTION VI

REFERENCES AND SELECTED BIBLIOGRAPHY

REFERENCES

Aurand, H.A., 1920, Mineral deposits of the western slope; Colo. Geol. Surv., Bull.
22.

Carpenter, Dr. R. , 1982, Personal Communication; Expert on the geology of
Colorado.

Colorado Division of Mines.

Craig, L.C. et al, 1955, Stratigraphy of the Morrison and related formations,
Colorado Plateau regional preliminary report; U.S.G.S. Bull 1009-E, pp
125-168.

Engineering and Mining Journal, Dec. 1982.

Gilraour, Dr. P., 1982, Personal Communication; Expert on Precambrian mineral
resources .

Heylmun, E. , 1982, Personal Communication; Knowledgeable on oil, gas and oil shale
deposits of the western U.S.

Landis, E.R., 1959, Coal resources of Colorado; U.S.G.S. Bull. 1072-C

Molenaar, CM., 1981, Mesozoic stratigraphy of the Paradox Basin - an Overview; in
Geology of the Paradox Basin, Rocky Mtn. Assoc. Geol. Field Conf . Guidebook,
pp 119-127.

National Park Service (NPS), 1982, File Data

Nelson-Moore, J.L., et al., 1978, Radioactive mineral occurrences of Colorado and
bibliography and uranium occurrences of the Uravan Mineral belt; Colo. Geol.
Surv. Bull. 40.

Robinson, C.A. et al, 1975, Mineral resources map of Moffat County, Colorado; Colo.
Geol. Surv., Open File Rept. 7 5-3.

Rowley, P.D. et al, 1979, Geologic map of the Vernal 1° x 2° quadrangle, Colorado,
Utah and Wyoming; U.S.G.S. Misc. Field Studies, Map MF-1163, Scale 1:250,000.

Schwochow, Stephen D., 1978, Mineral resources survey of Mesa County - a model
study; Colo. Geol. Surv., Resource Series 2, 110 p.

Sears, J.D., 1962, Yampa Canyon in the Uinta Mountains, U.S.G.S. Prof. Paper
374-1.

Unterman, G.E. et al, 1954, Geology of Dinosaur National Monument and vicinity;
Utah and Colorado; Utah Geol. & Min. Surv., Bull. 42

VI-1

Vanderwilt, J.W., L947, Mineral Resources of Colorado; Colo. Min. Res. Board,
547 p.

Young, R.G., 1955, Sedimentary facies and intertonguing in the Upper Cretaceous of
the Book Cliffs, Colorado and Utah; GSA Bull., Vol. 66, No. 2, p. 177-201.

BIBLIOGRAPHY

Carrara, P.E., 1980, Surficial geologic map of the Vernal 1° x 2° quadrangle,
Colorado and Utah, U.S.G.S. Misc. Invest. Series 1-1204.

Cashion, W.B., 1967, Geology and Fuel Resources of the Green River Formation,
Southeast Unita Basin, Utah and Colorado; U.S.G.S. Prof. Paper 548.

Collins, M.J., 1921, Some Anticlines of Moffat County, Colorado; Master's,
Colorado.

Hansen, Wallace R., 1977, Geologic map of the Canyon of Lodore South quadrangle,
Moffat County, Colorado; U.S.G.S. Geologic Quadrangle Maps, GQ-1403, scale
1:24,000.

Hansen, Wallace R. , 1978, Geologic map of the Zenobia Peak Quadrangle, Moffat
County, Colorado; U.S.G.S. Geologic Quadrangle Maps, GQ-1408, scale
1:24,000.

Hilpert, L.S. (ed.), 1964, Mineral and water resources of Utah; Utah Geol. & Min.
Surv. Bull. 73, 275 p.

Mayer, Victor J., 1964, Stratigraphy and paleontology of the Mississippi formations
of Moffat Co., Colorado; Colo. Mtn. Geol., Vol. 1, No. 1, p 25-34.

Miller, A.E., 1977, Geology of Moffat County, Colorado; Colo. Geol. Surv., Map
Series No. 3, scale 1:126,720.

Pruitt, R.G., Jr., 1961, The mineral resources of Uintah County, Utah Geol. & Min.
Surv. Bull 71, p 101.

Rowley, P.D., 1979, Geologic map of the Vernal 1° x 2° quadrangle, Colorado, Utah
and Wyoming; U.S.G.S. Miscellaneous Field Studies, Map MF-1163, scale
1:250,000.

Tweto, Ogden, 1975, Preliminary geologic map of the east half of Vernal 1° x 2°
quadrangle, Colorado; U.S.G.S. Open File Report 75-588.

Unterman, G.E., 1954, Geology of Dinosaur National Monument and vicinity; Utah and
Colorado; Utah Geol. Mineralog. Sur . Bull. 42.

Unterman, G.E., et al . 1964, Geologic map of Uintah County, Utah, scale 1/2 inch =
1 mile; Utah Geol. & Min. Surv. Map No. 16.

U.S. Geological Survey and Colorado Geological Survey, 1977, Energy resources map
of Colorado; U.S.G.S. Misc. Geol. Inv. Map 1-1039.

VI-2

BIBLIOGRAPHY
(cont . )

U.S. Department of Energy, Aerial radiometric and magnetic survey, Vernal National

Topographic Map, Colorado/Utah, Geo-Life, Inc., 230 p., 134 fiche; DOE

Contract No. EW-77-C-13-1678; SBA Contract No. SBO-308(a)-77-C-058; PR No.
79-146; 11/30/79, Report No. GJBX-167(79).

U.S. Department of Energy, Preliminary report on the geology of uranium deposits in
the Browns Park Formation in Moffat County, Colorado, and Carbon County,
Wyoming, by Allen Ormond, 1957, Report No. TM-D-1-18.

U.S. Department of Energy, Reconnaissance for uranium in the Chinle Formation in
and adjacent to Dinosaur National Monument, Uintah County, Utah, and Moffat
County, Colorado, N. B. Young, January 1955, 4 p., 2 illus.; PR No. 79-39;
4/10/79, Report No. TM-69.

U.S. Department of Energy, Reconnaissance of uranium-bearing deposits, Yampa River
Region, Colorado, R. P. Darnell, July 1952, 9 p., 1 illus.; PR No. 79-39,
4/10/79, Report No. TM-15.

U.S. Department of Energy, Uranium hydrogeochemical and stream sediment reconnais-
sance data release for the Red Creek Quartzite Special Study area, Vernal
NTMS Quadrangle, Utah/Colorado, including concentrations of Forty-Six addi-
tional elements, Sue Goff, et al., Los Alamos Scientific Laboratory, April
1981, 33 p.; LASL No. LA-8484-MS; PR No. 81-96; 6/29/81, Report No.
GJBX-173(81).

U.S. Department of Energy, Uranium resource evaluation, Vernal 1° x 2° Quadrangle,
Colorado-Utah, L. C. Craig,, W. J. Hall, Jr., and S. J. Luft, U.S. Geological
Survey, February 1980, 2 vol., 860 p., 16 illus.,; Contract No.
DE-A113-78GJ01686; PR No. 80-190; 12/17/80, Report No. PGJ-026(80).

U.S. Department of the Interior and Department of Agriculture, 1981, Moon Lake
Power Plant Project, Units 1 and 2, Environmental Impact Statement; Bureau of
Land Management, and Rural Electrification Administration, Vernal District
Office, Utah.

VI-3

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