DEPARTMENT OF THE INTERIOR

U.S. GEOLOGICAL SURVEY

National Petroleum Assessment

Western Basin and Range Province

(Province 83)

By Harry E. Cook1

Open-File Report

87-450L

.S. Geological Survey, 345 Middlefield Rd., MS 999, Menlo Park, CA

This report is preliminary and has not been reviewed for conformity with U.S.

Geological Survey editorial standards and stratigraphic nomenclature.

1987

INTRODUCTION

Basin Location and Size

Province 83 encompasses about one-half of Nevada (Fig. 1). To call this

province a single basin is obviously a misnomer. This province represents a

collage of diverse basins and basin types that evolved in response to a number

of sedimentologic and tectonic episodes along the western margin of North

America (Figs. 2,3).

QUALITATIVE EVALUATION OF HYDROCARBONS

Within Province 83 the possibility of commercial accumulations of

hydrocarbons is low. However, one area in Pershing County (Dixie Valley,

lat. 40°N. and long. 117°45 fW.) has been identified as a speculative play.

This area is attractive enough to warrant additional field mapping and sam­

pling the potential source and reservoir facies. This play, the Dixie Valley

Play, is discussed below.

REGIONAL GEOLOGIC FRAMEWORK

This section will attempt to outline the regional structural setting and

geologic history of the Cordillera. To gain a true perspective of the geo­

logic evolution of western Nevada, one must look beyond this man-made boundary

into eastern Nevada and California. The regional tectonics and stratigraphy

of these three Cordilleran provinces have an intimate interwoven genesis that

dates back to the Proterozoic (Figs. 2-6). Plate tectonic theory will be

124*

42'

40'

38'

36'

34

122' T~

120* 118' 116* 114*

WESTERN NEVADA

SIERRA NEVADA^ /

r: v

0

0 50

50 100 MILES

>0 100 KILOMETERS

FlGUEK ^ Index map of California ahowing the geomorphic division* of the Eastern California province (81A) in Stiples and Western Nevada, Basin and Range Province (83) in hachures. Modified after Scott (1983).

la

MESOZOIC ACCRETED TERRANE

PMI?cTTEO'-^'- "'06EOCUNE V TERRANE//. ' 7 >*.'. '.

Latt Precambrian adga of continent

... .. Middla Triattic edge of ccntinant

Early Tartiary adga of continent

Figure 2. Major components of Cordllleran "collage*1 V - "tfrangellla"; S - Stlkine arc; SD - "Seven Devlla" arc.

From Davis et al (1978)

Ib

*i*CorHinentOl Slopt^, S uj (Z km isoboth) ȣ ~

** 4

PACIFIC

OCEAN

Piovinces of Kiomoth

te«iern Kicmoth belt lo, O'doncion ocean

floor, Silurian (XC ft, Po'»o70'C oceontc

cru*t ond mantle Ic, Oevonian-Ptrrnien

island ore

volcanic rockc 2 Central metomorphiC belt,

o tC'Op of o Devonianecoflen.c belt

3.Weslern Permian and Triatsict*'i of ocean-floor racks

4 Western Jo'OiSiC b*tt, Upp«rJuroine volcanic rock*

100 SOO KILOMETERS

::soNQ«A^v

Figure 3 . Tectonic elements of California, Nevada, ond neighboring regions.

From Hamilton (1969)

Ic

INEVADA

. PM-TR SONOMA OROGE

DEV-MISSANTLER OROGENY

CRET-EOC OVERTHRUST BELT

CALIFORNIA

Figure A. Map showing locations of Permo-Triassic Golconda thrust, Devonian-Mississippian Roberts Mountains Thrust, and the Cretaceous-Eocene Sevier thrust of the Overthrust Belt. From Cook and Taylor (1983).

Id

GEOLOGIC COLUMNUYBP

50-

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150-

200-

250-

500-

350-

400-

450-

500-

550-

00-

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CARBON­ IFEROUS -

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MISS

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5 7

SILURIANL«

ORDOVICIAN M

1

CAMBRIAN

AM

M

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PRECAUBRIAN

MAJOR TECTONIC EVENTS 1CORDilLERAN

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9

FIVE MAJOR EVENTS

5

4

3

2

1

Figure 5. Major tectonic events in the Cordi&eran, From Cook and laylor (1983).

le

PACIFIC MARGIN ATLANTIC MARGIN1YBH

100-

200-

300-

400-

500-

600-

700-

800-

CENOZOIC> . .

CRETACEOUS

JURASSIC

TRIASSIC

PERMIAN

PENNSYLVAN1ANMISSISSIPPIAN

DEVONIAN

SILURIAN

ORDOVICIAN

CAMBRIAN

PRECAMBRIAN

. .*: . . *. . ' .-. " '. . . . . . : '. . "CIRCUM- PACIFIC

' SUB DUCT ION-:.-: s * * *

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.-^ARC |-*-SON

| OOU

j MJD-

^^"ANTl

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PRE*^" R

Y STEM . : /.' » » ..**. . . . ........

: '"L ' ' ' ' '

ACCRETION (?) OMA OROGENY

IRRH BASIN

CARBONIFEROUS RIFTING -ER OROGENY

Z

< LU

IT Z

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0 0 * 0o 0 ^

-WINDERMERE IFTING

.* - ..». . . / : .

. . . . /.-. v.v/.V-V. ..'. ATLANTIC:;.-.: ;':bCEAN:'/.:V. ' SPREADING-'.-'.'-* * **.*. \ " *!*«*/ ** * * » * »* ».* »

-*- PANGAEA ASSEMBLED

|-*-OUACHITA OROGENY

{-^-ACADIAN OROGENY

|-*-TACONIC OROGENY

"1 INITIAL FORMATION f OF ANADARKO-ARDMORE

J AULACOGEN

«

^ ^ RIFTING ON fol "^ ARCTIC MARGIN [ J

PRE-APPALACHIAN "^"" RIFTING

Flgurt V ̂ -Diagram to Illustrate approximate relative timing of key events on Pacific aad Atlantic aarglns of North America. * . "

From Dickinson (1977).

If

liberally used to understand the complex geologic history of the Cordillera.

This theory appears to offer unique unifying insights into the origin of the

diverse tectonic-sedimentologic regimes in the provinces of Nevada and

California.

Five tectonic events shaped the western margin of North America in the

vicinity of California and Nevada (Fig. 5). Some of these events are confined

to each respective province, but some events were of broader scale, and

affected the entire western margin of North America simultaneously.

Event 1: Proterozoic Crystalline Basement

Strontium and neodymium isotopes have been used to define Precambrian

crystalline basement of Proterozoic age. This continental crust is inferred

to extend as far west as central Nevada (Fig. 7, ISr = 0.706) (Kistler, 1974;

Farmer and DePaolo, 1983). Extensive metamorphism and intrusion of this base­

ment occurred between 1,650 and 1,750 Ma (King, 1969).

Event 2: Late Precambrian Through Devonian

Continental Rifting and Passive Margin Development

The Proterozoic continent was broken by a major rifting event near the

end of the Precambrian (Figs. 8,9) (Stewart, 1972; Stewart and Suczek,

1977). Until the end of the Devonian a passive continental margin comprised

western North America from Alaska to southeastern California (Figs. 10,11)

(Churkin, 1974; Cook and Taylor, 1975). This rifting and initial development

of the Cordilleran miogeocline is not well dated directly, but stratigraphic

backstripping indicates that rifting happened between 625 and 550 ma (Bond and

200H

fcn

Figure 7'. Map of the cen­ tral part of (he western United States Cordillera, showing Pre- cambrian and early PaJeozok tectonic features in relation to the COCORP 40eN Transect From Miller and Bradfisb (1980), ZarUnan (1974), Stewart (1980), Speed (1982), andFanner and DePaolo (1983). %

From Allmendinger et al (f987).

f~7~~J Basin & Range

Metamorphic Core ComplexesMuscovite granite belt (full extent not shown)

Accreted terranes

Precambrian basement exposures

Pigura 8 .-Diagram showing a model of the Ittt Precambrian and Cambrian developmtnt of the western "United StateaFrom Cook and Egbert (1*981).

RIFTING AND DEVELOPMENT OFWESTERN U.S.A. PASSIVE

CONTINENTAL MARGIN625-550 M.A.

WEST

CA

EASTI

NEVADA- 500 KM

UTAH

OCEANIC CRUST 'rrrt^T' - CONTINENTALoTAGic v I .MOT" *'\

HINGE LINE

SONOMANOROGENYPM.-TR.

ANTLER OROGENY DEV.-MISS.

SEVIEROROGENYCRET.-EOC.

Sleuarl (19721, Cook & Taylor (1975), Allmendinger el tl 11987)

Figure 9. From Cook and Taylor (1987).

2b

!« * Ut*

MAJUft STIUTILMAPMIL- ill*

Figure 10. General location of »ectlona In the Hot Creek Range and central Egan Range, Nevada, In relation to major regional stratigrcphic belu v . *

From Cook and Taylor (1977).

2c

LATE PRE-CAMBRIAN THROUGH LATE DEVONIAN

PASSIVE PULL-APART MARGIN

CONTINENTALMARGIN

I I' I

CARBONATEPLATFORM

I

100 KM

Figure 11. Paleogeographlc map,

2d

Kominz, 1984). On the basis of sedimentologic and biostratigraphic analyses

between Asia and western North America, Cook and Taylor (1975) established

that this rifting event occurred no later than about 520 ma.

This passive continental margin became the site of 5,000 m of shoal-water

carbonate platform and basinal sediments from the Cambrian through the

Devonian (Figs. 12,13) (Cook and Taylor, 1983; Cook and Taylor, 1987).

Event 3: Late Devonian Through Triassic Terrane Accretion

Two major accretionary events occurred during the Late Devonian-Early

Mississippian (Antler orogeny, Roberts et al., 1958; Speed, 1982,1983), and

the Permian-Triassic (Sonoma orogeny, Sllberling and Roberts, 1962; Speed,

1979,1982,1983) (Figs. 4,5,12). During the Antler orogeny the Roberts Moun­

tains allochthon oceanic rocks were thrust eastward at least 100 km over the

continental slope and platform margin carbonates. This event formed the

Antler erogenic highlands and foreland basin (Figs. 4,12,14,15). Similarly,

during the Sonoman orogeny, oceanic rocks in the Golconda allochthon (Figs.

4,12) were thrust eastward about 50-75 km over previously deformed continen­

tal-margin sediments (Fig. 12). The Sonoman orogeny, however, involved less

crustal shortening than the Antler orogeny, and did not develop a foreland

basin, as was the case during the Antler orogeny (Fig. 16).

The tectonic model that is commonly called upon to explain the distri­

bution of lithofacies in both orogenies is that of a normal polarity arc; the

back-arc (inner-arc) basin (Fig. 14) develops as a normal-trapped marginal

basin (Fig. 17c). This model is basically a Japan sea-type (Mitchell and

Reading, 1969) orogen (i.e., a continent bordered by a marginal sea with a

nearby arc offshore (Dickinson, 1977).

RIFTING AND DEVELOPMENT OFWESTERN U.S.A. PASSIVE

CONTINENTAL MARGIN625-550 M.A.

WEST

CA

117'I

NEVADA-500 KM

EAST

UTAH

OCEANIC CRUST' x RIFT STAGE x | /w,', ,x

rt^^SIA ' '- - "^

/SONOMAN ANTLEROROGENY OROGENYPM.-TR. DEV.-MISS.

HINGE LINE

SEVIEROROGENYCRET.-EOC.

Stewarl 11972), Cook & Taylor (19751. Ailmendinger el al (1987)

Figure 12. From Cook and lay lor (1987)

3a

PASSIVE CONTINENTAL MARGIN WESTERN U.S.A.

WEST * NEVADA UTAH EAST

I I II

OCEANIC BASIN

MIDDLE INNERCONTINENTAL SHELF SHELF

MARGIN 500 KM "

Cook and Taylor 119831

Figure 13. Generalized Pre-Antler orogeny depositional profile fromwestern Utah to central Nevada. Based on data from Cook and Taylor (1975,1983,1987).

3b

LATE DEVONIAN - EARLY MISSISSIPPIAN

CARBONATE PLATFORM

100 KM

Figure 14. Paleogeographic map,

3c

FORMER CONTINENTAL SHELF

OUTER-ARC BASIN

KLAMATH- NORTH SlERRAN

ISLAND ARC

~J3£~* INNER ARC BASIN

T

ANTLER OROGENIC WGHLAND

FORELAND BASIN1

CRATONIC PLATFORM

Z~&)--' ' ^l^ ^-ss^^'^'f-f^- - ̂ ^ "ZZ2 /£ ̂ "-^/^ ggr -1 J= i^tl ~I_ ^^- / , V "^

Figure 15.Hypothetical and generalized diagram showing relation between latest Devonian and Mississippian island-arc system and North American continent during Antler orogenic deformation.

From Poole et al (1987).

EARLY MESOZOIC

42*

100 MM

Figure 16. Paleogeographic map. Early Mesozoic,

TIME 1 (BEFORE) TIME 2 (AFTER)CONTINENTAL-MARGIN

o

ISLAND ARC

INTERARCMARGINAL

BASIN

OCEANIC CRUST

CONTINENTAL CRUST

(A) MARGINAL ARC SEPARATION

INTRA-OCEANIC ISLAND ARC ISLAND

ARC

ARC-TYPE IGNEOUS

SUITE

RESIDUAL MARGINAL

BASIN

CD

UJH

O.K

UJ

QJ

Oor

CONTINENTAL CRUST

SPACE DENOTES WIDE OCEAN

(B) OCEAN BASIN CLOSURE

OCEAN BASIN CONTINENTALA / MARGIN

. j.. .^. - *& i»t««i»».««»»

NORMAL-TRAPPED MARGINAL BASIN

OCEANIC CRUST CONTINENTAL

CRUST

7'

(C) NORMAL POLARITY ARC

OCEANIC BASIN

TRAPPED OCEANIC

CRUST

CONTINENTAL MARGIN ISLAND

ARC

REVERSED-TRAPPED MARGINAL BASINt

OCEANIC CRUST CONTINENTAL CRUST

(D) REVERSE POLARITY ARC

TRAPPED OCEANIC CRUST

ORIGINS OF MARGINAL BASINS

Figure 1'-Sketches to Illustrate alternate origins for oceanic marginal aeaa.

From Dickinson (1977).

3e

Beginning sometime in the Triassic, scattered plutons were being emplaced

in eastern California (Fig. 18) (Speed, 1978a,b). Simultaneously, ophiolite

complexes were developing in northern California, signaling the beginning of

major subduction systems and batholithic intrusions that were to dominate the

Cordillera later in the Mesozoic.

Event 4: Cretaceous-Eocene Andean-Type Continental Margin

In the Jurassic-Cretaceous the continental margin evolved into a setting

similar to that of the modern Andes with eastward subduction beneath the con­

tinent (Fig. 20) (Hamilton, 1969, 1978; Allmendinger et al., 1987). The Cre­

taceous geology of northern and central California is dominated by three

coeval complexes, now considered to be synchronous responses to subduction of

the Pacific lithosphere beneath the North American continent (Hamilton,

1978). In the east is the Sierran magmatic arc and batholiths (Fig. 19), in

the center is the fore-arc (outer arc) basin into which the Great Valley

sequence accumulated, and to the west in thrust contact beneath the Great

Valley sequence is the chaotic Franciscan melange (Fig. 20). East of the

Sierra Nevada batholith the Basin and Range Province was undergoing fluvial

and lacustrine sedimentation and minor amounts of volcanic activity (Fig. 20).

This Andean-type subduction was responsible for numerous thrust faults

which telescoped sedimentary fades throughout much of the Cordillera. These

thrusts are especially well exposed in the Basin and Range Province. The

Sevier overthrust belt of Cretaceous to Eocene age was the largest of the

Mesozoic thrust belts, and extended from southern Nevada northward into Canada

(Fig. 4). Armstrong (1968) estimated about 100 km of eastward crustal short­

ening associated with the Sevier system.

ORE6.

B o s i n o I

Terrene

Ptovint Ml.

Vol conic

,orc-!contintntsuture

.* (Eorly Triottic)

-38'

Ponominl ^ *.

Inyo MU.

Figure ig^Map shoving paleogeographle terranea of early Kesozole marine province o'f the was tern Great Basin '

From Speed (1978 b).4a

Approximate limits of the Sierra Nevada batholith

Figure 19.Distribution of

granitic rocks in theSiena Nevada

J>atholith. (Source:Geological Society

of America) 100 200 Kilometers

From Norris and Webb (1976).

4b

"-ATE CRETACEOUS - TERT.ARV

FRANCISCAN PROVINCE

EXTENSIONALTECTONICS "

BASIN AND RANGE . BLOCK FAULTING OLIGOCENE-RECENT

ALLUVIAL FANSLACUSTRINE SEDS ASH-FLOW TUFFS

PROTOSAN ANDREAS

FAULT

PELONA OROCOPIA RIFTED-MARGIN BASIN

Figure 20. Paleogeographic map.

4c

Event 5: Oligocene-Recent Continental Extension

Extensional tectonics has characterized the western United States since

at least the mid-Oligocene (Fig. 21). During continental extension two dif­

ferent tectonic interactions occurred along the North American plate to the

west (Zoback et al., 1981). The earlier extension occurred during eastward

subduction, and revived arc volcanism. This extension is characterized by

low-angle normal faults (Allmendinger, 1987). These faults may have been the

result of gravitational collapse of a tectonically thickened crust (Coney and

Harms, 1984). In contrast, the typical basin and range morphology is charac­

terized by evenly spaced mountain blocks, bounded by high-angle normal

faults. These faults were produced during east-southeast extension that

began 10 ma (Zoback et al., 1981). Several models exist to explain this

later intracontinental extension (Fig. 22) (Allmendinger, 1987).

Continental extension allowed massive volumes of siliceous ash-flow tuffs

(ignimbrites) to extrude and cover much of the Basin and Range Province to

thicknesses up to 10,000 feet (3,000 m) (Figs. 23,24,25) (Cook, 1965; Cook,

1968). These fractured, welded ash-flow tuffs (ignimbrites) form many of the

hydrocarbon reservoirs in eastern Nevada (Bortz and Murray, 1979; Bortz, 1983,

1985).

During this same period of time large masses of marine graywacke,

mudstones, and oceanic carbonate seamounts, that formed above a subduction

zone, were being tectonically accreted on the western margin of northern

California (Fig. 20) (Tarduno et al., 1986).

EXPLANATION!

CONTINENTAL* AREAS

-30* Extensionoi foulf

Strike-slip faultArro#s indicate relative rnave -

ment Dashed where inferredOCEAN AREAS

Spreading ridge Dotted where inferred

Trench

Transform fault or fracture zone Arrows indicate relative

movement Dashed where inferred

300 MILES20

300 KILOMETERS

120 t

110*I

Figure 21.Distribution of late Cenozoic extenslonal faults, najor strike-slip faults, «nd physiographic provinces In western North Aoerica and present-day lithospheric plate boundaries. From Stewart (1978). States: WA, Washington; OR, Oregon; CA, California; CO, Colorado; ID. Idaho; MT. tontana; VY. Wyoming; NV, Nevada; UT, Utah; A2, Arizona; KM, few Mexico. Localities SRP, Snake River Plain: YE, Yellowstone.

From Stewart (1983).

5a

Figure 22.Simplified models of Intracontinental extension. (A) Classic horst and graben model, (B) subhorizontal-decoupling- zone model, (C) anastomosing shear-zone or lenses model, and (D) crustal-penelrating shear-zone model

From Allmendinger et al (1987).

5b

^ ;t*iA*tsf^rte 4 l &~i£*t* A| ^'i^g^ .. ^=4^ -. i"

CALIFORNIA

. \ NEVADA I

UTAH

ARIZONA

100 kfh43-34 m.y.

Figure 23. Distribution of 43- to 6-o.y.-old igneous rocks in Nevada, Utah, and parts of adjacent states. Proa Stewart and others (1*77).

From Stewart (1983).

5c

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Figure 25. Paleotectonic and paleogeographic maps. From Dickinson (1979).

DIXIE VALLEY PLAY

Play Description and Type

During Middle Triassic times the Dixie Valley area (lat. 40°N. and long.

117°45 f W.) was the site of 2,000 feet (1,200 m) of carbonate sedimentation

within a back-arc basin (Figs. 26-28). These marine carbonates belong to the

Star Peak Group (Figs. 29-32), and manifest themselves as a shoaling-upward,

seaward-prograding (westerly) basin-plain to platform-margin complex (Fig. 33)

(Nicols and Silberling, 1977). The Star Peak Group contrasts sharply with the

unconformably underlying Lower Triassic Koipato Group, which is composed of

siliciclastics and volcanics. Likewise, the Star Peak also is much different

than the overlying Upper Triassic Auld Lang Syne Group, a sequence of

metapelitic sediments and siliciclastic rocks (Nicols and Silberling, 1977).

Reservoir Rocks

Potential reservoirs in the Triassic rocks (ex. Favret Formation) could

consist of carbonate turbidites and/or debris flows. However, whether or not

significant amounts of mass-flow carbonates with good reservoir characteris­

tics exist is not known at this time. Other potential reservoir rocks would

be in the platform-margin facies and dolomitized shelf-lagoon facies (Figs.

32,33) (i.e., Home Station and Panther Canyon members of the Augusta Mountain

Formation). However, this is speculative as these facies have not been

evaluated for their reservoir characteristics. Another type of potential

reservoir would be in the overlying densely welded and extensively fractured,

41*00*MT'OO1

40*00'

-.I:-:-:-:-;-:*:-:--:-***' N^ | t.

gx

^/VS^Kr-f^I J^' >

\j! /V>XJ *> \ N / /^ l<; - 1

i

\ ? miM| \ /$\*ir#A /Vi/ , \a J /?y^/

uroo' IIT^O*

Figure 2 6 lnd« niap showing location of Star Peak Group exposures (heavy stipple) in and near the Sonoma Range one-degree quadrangle (outlined by lightly stippled border). Locatioa of maps shown in Figure ^ jure indicated by labeled rectangles.

From Nicols and Silberling (1977).

6a

Ida.

DIXIE VALLEY

100 km

Figure 27 .^P shoving paleogeographic terranes of early Mesozolc marine and younger volcanic and intrusive rocks of the vestern Great Basin. Dash-dot line is isotopic 0.706 line.

Speed (1983).

6b

EARLY MESOZOIC

CARBONATE PLATFORM

100 KM

Figure 28. Paleogeographic map showing interpreted depostional setting for the Dixie Valley Play. Potential reservoir facies carbonate turbidites, debris flows, overlying prograding platform rocks, and fractured ignimbrites

NW SEAULD LANG SYNE GROUP

CANE SPRING FORMATION

«,?SMELSER PASS MEMBER

PANTHER CANYON MEMBER

KOIPATO GROUPAND

HAVALLAN SEQUENCE

10 milts

10 kifomttrts

HOME STATION MEMBER

II

H§

o.3 o

UJ 0.

Figurc29 Diagrammatic cross section of the Star Peak Group trending southeasterly from the northern Humboldt Range through the soutben Tobin Range to the Augusta Mountain*.

From Nicols and Silberling (1977).

6d

EXPLANATION

ALLUVIUM ond GRAVEL

VOLCANIC ROCKS CENOZOIC

GRASS VALLEY FORMATION

CANE SPRING FORMATION

Z<J^

$1" "^-low *

L 3

?D< 2nc e5 2> *

UPPE

T«pu

R ME

»- HOS

| SMELSER PASS MEMBERg Kot* VOLCANIC HOCKS

*CC X -Hop5

* PANTHER CANYON MEMBER 1

CONGRESS CANYON fe HOME STATION M

MBER FORMATI °N 89

Ipf

(ml IL_J p n

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STRATIGRAPWC CONTACT

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on Figure JW(facIng pages). Geologic maps of selected exposures of the Star Peak Group In

A, southern Humboldt Range; B, northern East Range; C, northern Stillwater Range; D, western

(other half of Figure 30 on next page)

From Nlcols and Silberling (1977).

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-40"I7'00"N

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31.CWna Mountain; E, northern Augusta Mountains; F, northern Fish Creek Mountains. Sec

- - . for locations. Arrow on map B delineates rocks included in the "Natchex Pass FormatJoa" of Ferguson and others (I95Ia). "

(other half of Figure 31 on previous page)

From Nicols and Silberling (1977).

6f

32Figure Time-stratigraphk correlation chart of the Star Peak Group at localities significant

for stratigraphic nomenclature. Small circles represent occurrences of age-diagnostic fossils; stippled pattern indicates secondary dolomite; vertical ruling indicates stratigraphk hiatus, and diagonal ruling Indicates lack of data.

From Nicols and Silberling (1977).

w»

LATE ANIStAN

BM0

Wmiig

EARLY LADINIAN MID LAWMAN

0 LATE LAWNtAN EARLY KARNIAN KARNIAN

SUPRATIOAL

TERRIGENOUS CLASTIC ROCKS

V» VOLCANIC ROCKS

UPLIFT AND EROSION

CARBONATE ENVIRONMENTS

Figure^^ PaJeogeographk maps of the Star Peak Group at different times during its deposition. Set Figure 5 for series assignment of Triassic stages. Area of maps is approximatley that in Figure 1; L, Lovelock; W, Winnemucca; BM, Battle Mountain. The map patterns correspond to those on the conventional model of near-short carbonate environments shown beneath the tape.

From Nicols and Silberling (1977).Art

welded ash-flow tuffs (ignimbrites) of Tertiary age. The ignirabrites that

occur in the mountain ranges surrounding Dixie Valley probably underly Dixie

Valley, and could be suitable as reservoir rocks. These same types of rocks

form reservoirs in the oil fields of Railroad Valley in eastern Nevada (Bortz

and Murray, 1979).

Traps and Seals

Both structural and stratigraphic traps could be expected if the Dixie

Valley Basin has undergone similar Cenozoic structural modifications as in

other parts of the Basin and Range Province. In this respect, one would be

employing an Eagle Springs oil-field model (i.e., the first oil field dis­

covered in Nevada), which utilizes both structural and stratigraphic traps

(Fig. 34).

A seismic profile across the Carson Sink Valley (Fallen Basin), ten miles

(16 km) west of Dixie Valley reveals an overall structural pattern similar to

that in Railroad Valley (Figs. 35,37). It is quite probable that the struc­

ture of Dixie Valley would be similar to that of Carson Sink Valley (Fallen

Basin).

Source Rocks

The petroleum industry is attracted to this area because the Triassic

basinal sediments may be potential source rocks (Bortz, 1983, 1985). The Fos­

sil Hill member of the Middle Triassic Favret Formation is a 600-foot-thick

sequence (180 m) of dark-gray calcareous shale and lime mudstone which crops

out in the mountain ranges flanking the northern part of Dixie Valley

WEST

j TRAP SPRING FIELD j

EAST

I EAGLE SPRINGS RELD I

ShellEsgto Springs Unit 2

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v» > .i 'iGi 1 . r'.V'ES^sss

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nAcctcnct «ah«t * Of Moom. Scon. »nd LumwUn. 196S

1 Of Ml*iUilppl*n lo r«rmUn *ft

Figure 3A. Generalized crou section of Railroad Valley showing rock units and vitrinite reflectance values obtained on cores froa tvo veils*»

From Poole et al (1983).

7a

Flgur* 3SGenerallzed geologic map of the Fallon basin compiled from Page (1965), Wlltden & Speed (1974), and unpublished geologic maps from the Southern Pacific Company.

From Hastings (1979).

7b

CONTOUR INTERVAL 2000 FT. (610M)

CONTOUR DATUM IS 3850FT. 11173 M) ABOVE SEA LEVEL

Figure -Subsurface structure conlour map of the northern Fallon basin drawn on the base of the Tertiary from reconnaissance Mlsmlc and gravity data.

From Hastings (1979).

7c

SEISMIC LINE NC-73-2 1924 MI

STANDARD - AMOCO 3 f LAND CO NO I KC U. Tf4N.H»« IlXV VK>0 U

SU L£WCL

£>^.-" : ' s;?1J^*/!**/??|-- "*' " -.

Figure -Seismic line NC-73-2. A. Is amplitude anomaly, B. the 'capping basalt* event, and C. the base of the Tertiary as Inter­ preted from discontinuous setsmic events and gravity modeling.

From Hastings (1979).

7d

(Figs. 30,31,38). This sequence contains ammonoids which, when broken open,

commonly yield hydrocarbons (Figs. 39,40) (Nicols and Silberling, 1977,

p. 21). If the Favret Formation is a good source rock for hydrocarbons, its

presence beneath the Cenozoic fill in Dixie Valley is highly probable.

Cenozoic lacustrine sediments are also a type of potential source rock in

the Basin and Range Province (Fouch, 1979; Fouch et al., 1979; Poole et al.,

1983; Poole and Claypool, 1984; Sandberg, 1983). In the Carson Sink Valley

(Figs. 38,41) 5,000 feet (1,525 m) of silts and clays have excellent source-

rock potential, but temperatures and depth of burial suggest that only modest

amounts of oil have been generated from these rocks (Hastings, 1979).

Potential source rocks in the Paleozoic have been analyzed for their

thermal maturity. Data based on conodont alteration index (CAI) values

suggest that the Paleozoic sediments in western Nevada have been intensely

baked and have CAI values 4.5 (Fig. 42) (Epstein et al., 1977).

Depth of Occurrence

The depth of the reservoir targets are uncertain, but may be on the order

of 5,000-10,000 feet (1,500-3,000 m) for Tertiary ignimbrites, and 10,GOO-

15,000 feet (3,000-4,500 m) for Mesozoic carbonates.

Exploration Status

At least a dozen geothermal wells have been drilled in Dixie Valley which

range in depth from 3,000-12,000 feet (900-3,750 m) (Fig. 38) (Bortz, 1985).

The only well drilled as an oil and gas exploratory well is the Standard-Amoco

No. 1 S.P. Land Co. (Sec. 33, T. 24 N., R. 33 E.). This is located in the

T" /Dixie Valley Area Geologic Map0 5 10

Figure ' Dixie Valley erea. Qs - Quaternary alluvial and playa deposits; Qb - Qua­ ternary basalts; TV - Tertiary volcanics; J*s - Upper Triassic and Lover Jurassic sediments and volcanic rocks; 1»c - Lower, Middle, and Upper Triassic (Tobln, Dixie Valley, Favret and Augusta Mtns. fos.); *k - Lower Triassic Koipato volcanic and clastic rocks; Tji, Ki, Ji, »i - Intrusives; © - Ceo- thenna1 well or test;A ~ Minor oil show; A - Minor gas show; A ~ Surface oil show.

From Bortz (1983).

Figure * ' Concretion of calcareous mid stone ' from Triassic Favret formation in the August Mountains - chambers of this ammonite contained liquid hydrocarbons.

Figure 40 Outcrop of the Fossil Bill aeaber * of the Favret formation in the

Augusta Mountains.

From Bortz (1983).From Bortz (1983)

8a

STANDARD-AMOCO S.P LAND CO. NO. I

C-L06

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WT ft UTH TA1 Oftt. C

ft ALGMTE

WT ft ft C-LOG UTM TA1 0*6. C ALGMTC

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v V V JLyv ~, Itv~ V

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V V

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t 15 5 Oil 4 ft o so eo

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-Clectrlc log and llthotogic log of Standard-Amoco S.P. Land Co. *1. Thermal alteration Index values are from ditch samples, and weight percent organic carbon and percent alglnlte component values from sldewall samples.

From Bortz (1983).8b

THERMAL MATURITY BASED ON CONODONT ALTERATION INDEX VALUES (CAD

COLCONDA ROBERTS MTNS. <PM-TW THRUST 117" THRUST (DEV-MISS)

42'

BAKED PALEOZOIC) SOURCE RX I

CEOTHERMAL \ GRADCNTS \ OF~3HFU

f-90" C/KM) WIDESPREAD V

3EOTHERMAL HEATING\

OK. GENERATION UMfT Of OtPRESERVATION __

.CONDENSATE/WET 6A6 PRESERVATION LMfT NEC. as

Figure 42. Map showing thermal maturity of Paleozoic source rocks in Nevada. In general these rocks are supermature in western Nevada and submature-to-mature in eastern Nevada. Based on data in Epstein et al (1977) and Poole and Claypool (1984).

8c

adjacent Carson Sink Valley (Fallon Basin) (Fig. 38). This well penetrated

11,000 feet (3,300 m) of Tertiary playa sediments and volcanics (Fig. 41).

Oil and gas shows, including free oil in vugs at the top of a basalt core at

8,168 feet (2,490 m) were present in the well. Results of formation tests of

selected intervals showed that reservoir rocks were absent (Hastings, 1979).

As discussed above, potential lacustrine source rocks are available, but they

have not been subjected to sufficiently high temperatures to generate large

quantities of hydrocarbons.

SELECTED REFERENCES

*

Allmendinger, R. W., Hauge, T. A., Hauser, E. C., Potter, C. J.

Kleraperer, S. L., Nelson, K. D., Knuepfer, P., and Oliver, J., 1987,

Overview of the COCORP 40°N Transect, western United States: The fabric

of an orogenic belt: Geological Society of America Bulletin, v. 98, p.

308-319.

Armstrong, R. L., 1968, Sevier orogenic belt in Nevada and Utah: Geological

Society of America Bulletin, v. 79, p. 429-458.

Bond, G. C., and Kominz, M. A., 1984, Construction of tectonic subsidence

curves for the early Paleozoic miogeocline: Implications for subsidence

mechanisms, age of breakup, and crustal thinning: Geological Society of

America Bulletin, v. 95, p. 155-173.

Bortz, L. C., 1983, Hydrocarbons in the northern Basin and Range, Nevada and

Utah, in The role of heat in the development of energy and mineral

resources in the northern Basin and Range Province: Geothermal Resources

Council Special Report No. 13, p. 179-197.

Bortz, L. C., 1985, Hydrocarbons in the northern Basin and Range, Nevada and

Utah: Oil and Gas Journal, p. 117-122.

Bortz, L. C., and Murray, D. K., 1979, Eagle Springs oil field, Nye County,

Nevada, in Newroan, G. W., and Goode, H. D* eds., Basin and Range Sympo­

sium: Rocky Mountain Association of Geologists and Utah Geological

Association, p. 441-453.

Churkin, Michael, Jr., 1974, Paleozoic marginal ocean basin-volcanic arc sys­

tems in the Cordilleran foldbelt, in_ Dott, R. H., Jr., and Shaver, R. H.,

eds., Ancient and modern geosynclinal sedimentation: Society of Economic

Paleontologists and Mineralogists, Special Publication 19, p. 174-192.

Coney, P. J., and Harms, T., 1984, Cordilleran metamorphic core complexes:

Cenozoic extensional relics of Mesozoic compression: Geology, v. 12,

p. 550-554.

Cook, E. F., 1965, Stratigraphy of Tertiary volcanic rocks in eastern

Nevada: Nevada Bureau of Mines Report 11, 61 p.

Cook, H. E., 1968, Ignirabrite flows, plugs, and dikes in the southern part of

the Hot Creek Range, Nye County, Nevada, in Studies of volcanology:

Geological Society of America Memoir 116, p. 107-152.

Cook, H. E., and Taylor, M. E., 1975, Early Paleozoic continental margin

sedimentation, trilobite biofacies, and the thermocline, western United

States: Geology, v. 3, p. 559-562.

Cook, H. E., and Taylor, Michael E., 1977, Comparison of continental slope and

shelf environments in the Upper Cambrian and Lowest Ordovician of Nevada,

in Cook, H. E., and Enos, Paul, eds., Deep-water carbonate environ­

ments: Society of Economic Paleontologist and Mineralogists Special

Publication No. 25, p. 51-81.

10

Cook, H. E, and Egbert, R. M., 1981, Late Cambrian-Early Ordovician continen­

tal margin sedimentation, in M. E. Taylor, Short papers for the Second

International Symposium on the Cambrian system: U.S. Geological Survey

Open-File Report 81-743, p. 50-56.

Cook, H. E., and Taylor, M. E., 1983, Paleozoic carbonate continental mar­

gin: Facies transitions, depositional processes and exploration models

the Basin and Range Province: American Association of Petroleum Geolo­

gists Field Seminar Guidebook, 177 p.

Cook, H. E., and Taylor, M. E., 1987, (abs) Stages in evolution of Paleozoic

carbonate platform and basin margin types western United States passive

continental margin: American Association of Petroleum Geologists,

v. 71/5, p. 542-543.

Davis, G. A., Monger, J. W. H., and Burchfiel, B. C., 1978, Mesozoic construc­

tion of the Cordilleran "collage", central British Columbia to central

California, ln_ Howell D. G., and McDougall K. A., Mesozoic paleogeography

of the western United States, Pacific Coast Paleogeography Symposium 2:

The Pacific Section of the Society of Economic Paleontologists and

Mineralogists, p. 1-32.

Dickinson, W. R., 1977, Paleozoic plate tectonics and the evolution of the

Cordilleran continental margin, in Stewart, J. H., Stevens, C. H., and

Fritsche, A. E., Paleozoic paleogeography of the western United States,

Pacific Coast Paleogeography Symposium 1: The Pacific Section of the

Society of Economic Paleontologists and Mineralogists, p. 137-155.

Dickinson, W. R., 1979, Cenozoic plate tectonic setting of the Cordilleran

region in the United States, in Armentrout, J. M., Cole, M. R., and

Terbest, H., Jr., Cenozoic paleogeography of the western United States,

Pacific Coast Paleogeography Symposium 3: The Pacific Section of the

Society of Economic Paleontologists and Mineralogists, p. 1-13.

11

Epstein, A. G., Epstein, J. B., and Harris, L. D., 1977, Conodont color

alteration an index to organic metamorphism: U.S. Geological Survey

Professional Paper 995, 27 p.

Farmer, G. L., and DePaolo, D. J., 1983, Origin of Mesozoic and Tertiary

granite in the western United States and implications for pre-Nesozoic

crustal structure, 1. Nd and Sr isotopic studies in the geocline of the

northern Great Basin: Journal of Geophysical Research, v. 88,

p. 3379-3401.

Fouch, T. D., 1979, Character and paleogeographic distribution of upper Creta­

ceous (?) and Paleogene nonmarine sedimentary rocks in east-central*

Nevada, in Armentrout, J. M., Cole, M. R., and Terbest, H., Jr., eds.,

Cenozoic paleogeography of the western United States, Pacific Coast

Paleogeography Symposium 3: The Pacific Section of the Society of

Economic Paleontologists and Mineralogists, p. 97-111.

Fouch, T. D., Hanley, J. H., and Forester, R. M., 1979, Preliminary correla­

tion of Cretaceous and Paleogene lacustrine and related nonmarine sedi­

mentary and volcanic rocks in parts of the eastern Great Basin of Nevada

and Utah, Jjn Newman, G. W., and Goode, H. D., eds, Basin and Range Sympo­

sium: Rocky Mountain Association of Geologists and Utah Geological

Association, p. 305-312.

Hamilton, W., 1969, The volcanic central Andes a modern model for the Creta­

ceous batholiths and tectonics of western North America: Oregon Depart­

ment of Geological and Mineral Industries Bulletin, v. 65, p. 175-184.

________ 1978, Mesozoic tectonics of the western United States, in Howell,

D. G., and McDougall, K. A., eds., Mesozoic paleogeography of the western

United States: Society of Economic Paleontologists and Mineralogists,

Pacific Section, Pacific Coast Paleogeography Symposium, 2nd, p. 33-70.

12

Hastings, D. D., 1979, Results of exploratory drilling northern Fallon Basin,

western Nevada, in Newman, G. W., and Goode, H. D., eds., Basin and Range

Symposium: Rocky Mountain Association of Geologists and Utah Geological

Association, p. 515-522.

King, P. B., 1969, Tectonics of North America a discussion to accompany the

tectonic map of North America: U.S. Geological Survey Professional Paper

628, 95 p.

Kistler, R. W., 1974, Phanerozoic batholiths in western North America: A sum­

mary of some recent work on variations in time, space, chemistry, and

isotopic composition: Annual Reviews of Earth and Planetary Science,

'v. 2, p. 403-418.

Mitchell, A. H., and Reading, H. G., 1969, Continental margins, geosynclines,

and ocean floor spreading: Jour. Geology, v. 77, p. 629-646.

Nichols, K. M., and Silberling, N. J., 1977, Stratigraphy and depositional

history of the Star Peak Group (Triassic), northwestern Nevada: The

Geological Society of America Special Paper 178, 73 p.

Norris, R. M., and Webb, R. W., 1976, Geology of California: John Wiley, New

York, 365 p.

Poole, F. G., Claypool, G. E., and Fouch, T. D., 1983, Major episodes of

petroleum generation in part of the northern Great Basin, in The role of

heat in the development of energy and mineral resources in the northern

Basin and Range Province: Geothermal Resources Council Special Report

No. 13, p. 207-2213.

Poole, F. G., and Claypool, G. E., 1984, Petroleum source-rock potential and

crude-oil correlation in the Great Basin, ln_ Woodward, Jane, Meissner, F.

F., and Clayton, J. L., eds., Hydrocarbon source rocks of the greater

13

Rocky Mountain region: Rocky Mountain Association of Geologists,

p. 179-230.

Poole, F. G., Sandberg, C. A., and Boucot, A* J., 1977, Silurian and Devonian

paleogeography of the western United States, in Stewart, J. H., Stevens,

C. H., and Frltsche, A* E., Paleozoic paleogeography of the western

United States, Pacific Coast Paleogeography Symposium 1: The Pacific

Section of the Society of Economic Paleontologists and Mineralogists,

p. 39-65.

Roberts, R. J., Hotz, P. E., Gllluly, J., and Ferguson, H. G., 1958, Paleozoic

rocks of north-central Nevada: American Association of Petrolelum

Geologists Bulletin, v. 42, p. 2813-2857.

Sandberg, C. A., 1983, Petroleum potential of wilderness lands in Nevada, in

Miller, B. M., ed., Petroleum potential of wilderness lands in the west­

ern United States: U.S. Geological Survey Circular 902-A-P, p. H1-H11.

Scott, E. W., 1983, Petroleum potential of wilderness lands in California, in

B. M. Miller, ed., Petroleum potential of wilderness lands in the western

United States: U.S. Geological Survey Circular 902-A-P, D1-D12.

Silberling, N. J., and Roberts, R. J., 1962, Pre-Tertiary stratigraphy and

structure of northwestern Nevada: Geological Society of America Special

Paper 72, p. 1-50.

Speed, R. C., 1978a, Basinal terrane of the early Mesozoic marine province of

the western Great Basin, in Howell D. G., and McDougall, K. A., eds.,

Mesozoic paleogeography of the western United States, Pacific Coast Pale­

ogeography Symposium 2: The Pacific Section of the Society of Economic

Paleontologists and Mineralogists, p. 237-252.

_________, 1978b, Paleogeographic and plate tectonic evolution of the early

Mesozoic marine province of the western Great Basin, in Howell, D. G.,

14

and McDougall, K. A., eds., Mesozoic paleogeography of the western United

States, Pacific Coast Paleogeography Symposium 2: The Pacific Section of

the Society of Economic Paleontologists and Mineralogists, p. 253-270.

________, 1979, Collided Paleozoic microplate in the western United

States: Journal of Geology, v. 87, p. 279-292.

____, 1982, Evolution of the sialic margin in the central western United

States, _in_ Watkins, J., and Drake, C., eds., Geology of continental

margins: American Association of Petroleum Geologists Memoir 34,

p. 457-468.

______, 1983, Precenozoic tectonic evolution of northwestern Nevada, in

The role of heat in the development of energy and mineral resources in

the northern Basin and Range Province: Geothermal Resources Council

Special Report No. 3, p. 11-24

Stewart, J. H., 1972, Initial deposits in the Cordilleran geosyncline:

Evidence of a late Precambrian (> 850 m.y.) continental separation:

Geological Society of America Bulletin, v. 83, p. 1345-1360.

Stewart, J. H., and Suczek, C. A., 1977, Cambrian and latest Precambrian pale­

ogeography and tectonics in the western United States, in Stewart, J. H.,

Stevens, C. H., and Fritsche, A. E., eds., Paleozoic paleogeography of

the western United States: Society of Economic Paleontologists and

Mineralogist Pacific Section, Pacific Coast Paleogeography Symposium I,

p. 1-17.

Stewart, J. H., 1983, Cenozoic structure and tectonics of the northern Basin

and Range Province, California, Nevada and Utah, in The role of heat in

the development of energy and mineral resources in the northern Basin and

Range Province: Geothermal Resources Council Special Report No. 13,

p. 25-40.

15

JTa£duno, J. A., McWilliams, M., Sliter, W. V., Cook, H. E., Blake, M. C., Jr.,

and Premoli-Silva, I., 1986, Southern hemisphere origin of the Cretaceous

Laytonville Limestone of California: Science, v. 231, p. 1425-1428.

Zoback, M. L., Anderson, R. E., and Thompson, G. A., 1981, Calnozoic evolution

of the state of stress and style of tectonism of the Basin and Range

Province of the western United States: Royal Society of London Philo­

sophical Transactions, v. A-300, p. 407-434.

16