DEPARTMENT CF THE INTERIOR CALIFORNIA—NEVADA
GEOLOGICAL SURVEY 15 MINUTE SERIES (TOPOGRAPHIC)
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TOPAZ LAKE, CALIF.—NEV.

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327 North A-nericac RLOMETERS,

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CONTOUR INTERVAL 80 FEET
NAL GEQDETIC VERTICAL DATUM OF 1929

Universal trapsweise Mercator ged

§ QUADRANGLE TOGATION

Kis MAP COMPLIES WITH NATIONAL MAP ACCURACY STANDARDS
FOR SALE BY U S. Ged SURVEY, DENVER, COLORADO 80225, OR RESTON, VIRGINIA 22092
2» FOLDER GRIEG TOPOGRAPHIC MAPS AND SYMBOLS IS AVAILABLE ON REQUEST

‘ AMS 2061 H—-SERIES V795

indicates ana
Btchaneon &

and (ine. sodk gle angroximate fovations 1956

RECONNAISSANCE GEOLOGIC MAP|OF THE TOPAZ LAKE 15 MINUTE QUADRANGLE,
CALIFORNIA AND NEVADA

By s

This map is preliminary and has
not been reviewed for conformity

. with U.S. Geological Survey editorial
standards and stratigraphic nomenclature.

David A. John, Jamies Giusso, William J. Moore, and Richard A. Armin

with Quaternary geology by John C. Dohrenhend

1981

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CORRELATION OF MAP UNITS

OPEN-FILE REPORT

81-273
Sheet 1 of 1

SYMBOLS

Geologic contacts, dashed where approximately located,
dotted where concealed

Faults, dashed where approximately located, dotted where
concealed; bar and ball on downthrown side

‘Thrust faults; sawteeth in upper plate

Strike and dip of flow foliation in volcanic rocks

Strike and dip of foliation in metamorphic rocks

Sections within the Relief Peak Formation comprised
dominantly of andesitic lahars

INDEX TO GEOLOGIC MAPPING
John, D. and Moore W. J+, Reconnaissance geologic mapping 1980
assisted by L. Lynch with information from:

1. Curtis (1951)

2. Wachter (1971)

3. Wilshire (1957)

John, D., and Armin, R+, Reconnaissance geologic mapping 1980 with
Anformation from:

4. Curtis (1951) and Stanford Geology Survey (1964)

5. Schwetkert (1972)

Simplified from D. Hudson (1980), unpublished mapping.
Giusso, J., Reconnaissance geologic mapping 1979,
information from:

7, Stanford Geologic Survey (1964)

8 Curtis (1951)

9. Wilshire (1957)

Quaternary geology by J. C- Dohrenwend (1979, 1980).

1980 with

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Pliocene |
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relations age |
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relations faeaene unknown
unconformity unknown | aves! wv"36!
son al unknown TERTIARY fey
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Miocene _
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unconformity 45.
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unconformity 6
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; Upper
Keg [Kea cree CRETACEOUS
unconformity 19.
Cretaceous—
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unconformity { :
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unconformity sail
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Upper Triassic =
TRIASSIC ,
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- SILVER PEAK ANDESITE (Wilshire, 1957) (late Miocene)--Similar to the RELIEF PEAK FORMATION (Slemmons, 1966) (Miocene)--Undifferentiated
i Relief Peak Formation. Unaltered andesitic lahars and breccias andeBite and basalt flows, flow breccias, lahars, minor shallow
predominate but unit also includes hornblende pyroxene andesite intrusive rocks, and minor volcaniclastic sediments. Includes
ARTIFICIAL FILL~~Teilings at the Leviathan mine flows and minor quantities of pyroclastic rocks and volcaniclastic pyroxene andesite lahars, hypersthene-augite andesite flows,
COLD SPRING DEPOSITS (Holecens)—Actively forming: light-brown sediments. Unlike the Relief Peak Formation, the andesite flows hornblende-hypersthene-augite andesite flows, minor olivine basalt
calcareous cold spring deposits west of Poison Flat. Numerous Generally the

other cold spring deposits nearby are too small to show at map
scale

YOUNG ALLUVIAL FAN DEPOSITS (Holocene)-~Poorly sorted bouldery sand
and gravel. Includes some valley-fill deposits in low-gradient
valleys where distal fan limits are gradational and poorly
defined. Fan surfaces are undissected to slightly dissected with
few, if any, well-defined drainage channels. Fan drainage is
distributary, radiating fron the fan apex- Generally unweathered,
with weak, if any, soil profile development

UNDIFFERENTIATED YOUNG AND INTERMEDIATE ALLUVIAL FANS (Holocene-late
Pleistocene)--Mapped in areas where young and intermediate fan
surfaces are too complexly interrelated to be mapped separately or
where more precise age relationships could not be determined

INTERMEDIATE  ALLUVIAL FAN DEPOSITS ~=—(Pleistocene)--Similar
lithologically and sedimentologically to young alluvial fan
deposits. Contacts between young and intermediate alluvial fan

deposits are commonly gradational and poorly defined. Intermediate
alluvial fen surfaces are slightly to moderately dissected, with
numerous well-defined well-incised drainage channels. Drainage is
predominantly distributary, but some channels head on the fan
surface. Relief due to dissection 1s generally less than 7 m
Constructional surfaces are slightly to moderately weathered with
weak to moderate soil profile development. Limited to the larger
nonglactated valleys (Bagley, Slinkards, Little Antelope, and
Antelope Valleys)

UNDIFFERENTIATED INTERMEDIATE AND OLD ALLUVIAL AN DEPOSITS
(Pleistocene)--Mapped in areas where intermediate and old alluvial
fan deposits are too complexly interrelated to be mapped separately
or where more precise age relationships could not be determined.
Limited to the northeast side of Slinkards Valley and the south end
of Bagley Valley

OLD ALLUVIAL FAN DEPOSITS (Pleistocene)--Similar lithologically to
young and intermediate alluvial fan deposits. Fan surfaces are
deeply dissected by well-developed subparallel drainage that heads
on the fan surface. Relief due to dissection 1s commonly 5 to
15m Constructionel fan surfaces are strongly weathered with
moderately well to well developed soil profiles. Limited to one
area at the north end of Slinkards Valley

PLAYA DEPOSITS (Holocene)--Layered sand, silt, and clay in the
bottoms of dry ponds and lakes. Occurs in a few small structurally
controlled depressions in upland areas of the northern part of the
quadrangle

LANDSLIDE DEPOSITS (Holocene)--Unsorted angular boulder- to clay-size

debris. Occur generally as lobate masses in steep mountain
areas. Includes talus and colluvium overlapping and intermixed
with the landslide debris. Over 20 major landslides occur in the
quadrangle, and approximately 70 percent of these involve Tertiary
volcanic rocks. Seven landslides exceed 1 kn” in area

VALLEY-FILL DEPOSITS (Holocene)--Undifferentiated alluvium underlying
low-gradient floors of alpine valleys. Includes stream channel and
flood plain alluvium, low-gradient alluvial-fan deposits, glacial
outwash deposits, and lacustrine deposits, often associated with
glacial drift. - Limited to the valleys of Wolf Creek and the East
Fork of the Carson River

‘FLOOD-PLAIN ALLUVIUM (Holocene)--Moderately to poorly sorted gravelly
to silty sand and sandy to clayey silt. Stream channel and
overbank deposits along low-gradient streams (the West Walker River
and the East Fork of the Carson River). Associated with typical
low-relief flood-plain topography

ROCK GLACIER DEPOSITS (Holocene)--Highly angular bouldery gravel.
Unweathered. Including and closely associated with blocky talus.
Characterized by distinctive lobate morphology. Limited to one
area between 9,000 and 9,600 ft on the east flank of the ridge
between Wolf Creek and Dumonds Meadows

GLACIAL MORAINE DEPOSITS (late Pleistocene--Tioga through Tahoe
age)-—Unsorted to very poorly sorted bouldery to clayey gravel that
1s slightly compacted. Associated with undissected to slightly
dissected sharp crested lateral moraines and slightly to moderately
dissected terminal moraines. Granitic boulders on surface are
slightly to moderately weathered and soil profiles generally are
weakly developed. Includes some talus, valley fill, and alluvial
fan deposits which are intimately associated with the glacial drift
and too small to be mapped separately. Limited to elevations above
8,000 ft in Bull Canyon

UNDIFFERENTIATED GLACIAL MORAINE DEPOSITS (Pleistocene)--Unsorted to
very poorly sorted bouldery to clayey gravel. Generally lacks
diagnostic constructional form. Limited to areas southwest of the
East Fork of the Carson River and Silver King Creek

BASALT (Pleistocene)--Light-gray to black finely porphyritic olivine
basalt flows. Contain sparse small phenocrysts of fresh olivine,
plagioclase, and augite in an aphanitic groundmass

GRAVEL DEPOSITS (Pleistocene)--Poorly to moderately sorted
silt, sand, and gravel. Preserved as discontinuous fluvial terrace
remnants along the East Fork of the Carson River downstream from
the mouth of Wolf Creek

PEDIMENT DEPOSITS (Pleistocene)~-Lithologically, sedimentologically,
and morphologically similar to older alluvial fan deposits, except
that the pediment deposits occur as veneers on pedimented
bedrock. Limited to one up-faulted area at the northeast end of
Little Antelope Valley 3

GRAVEL DEPOSITS (Pleistocene and (or) Pliccene)—-Coarse unsorted
subrounded bouldery sand and gravel. Limited to the head of a
north-trending drainage about 6,000 ft between Slinkards and
Antelope Valleys and the gouth end of Gold Hill

PEDIMENT DEPOSITS (Pleistocene and (or) Pliocene)~~Coarse subangular
gravel and sandy gravel. Caps 80 m high erosion surface remant at
the north end of Slinkards Valley

YOUNGER ANDESITE (late Miocene-early Pliccene)—-Dark-gray porphyritic
hornblende hypersthene andesite flow containing 5 to 7 percent, 1-
to 5-mm phenocrysts of plagioclase, hypersthene, and hornblende in
an aphanitic groundmass. Overlies the dacite of Silver. Peak

DACITE OF SILVER PEAK (late Miocene-early Pliocene)--Highly variable
orange to white flow-banded locally vesicular glassy porphyritic
biotite dacite and rhyolite flows exposed on the east flanks of
Silver and Wghland Peaks along the extreme western edge of. the
quadrangle. Contain approximately 10 to 12 percent phenocrysts “of
plagioclase, biotite, sanidine, quartz, and hornblende set in
colorless to pale-brown glass. Overlies the Silver Peak Andesite

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commonly have weak columnar and platy jointing.
basal contact with the Relief Peak Formation was placed at a break
in slope, although in other places the contact is more or less
arbitrary (also see Wilshire (1956, p- 70)

DACITE OF UPPER WOLF CREEK (late Miocene-early Pliccene)-—Light-gray
finely vesicular porphyritic quartz augite hornblende dacite flows
and intrusions overlying and intruding the Disaster Peak and Relief
Peak Formations on a ridge approximately 5 km west of Soda Springs
Guard Station

DISASTER PEAK FORMATION (Slemmons, +1966) (Miocene)——Thin volcanic
sequence of gray to brown unbrecciated and autobrecciated
hornblende-rich andesite flows; heterogeneous light-gray to pink
andesitic lahars; and minor amounts of brown volcaniclastic
sediment: The andesite flows typically contain hornblende
phenocrysts up to 6 mm long in a fine-grained gray groundmass. The
Disaster Peak Formation unconformably overlies the Stanislaus Group

STANISLAUS GROUP, UNDIFFERENTIATED (Slemmons, 1966; Noble and others,
1974) (Mfocene)~In the map area consists of Table Mountain Latite
and Eureka Valley Tuff. Comprises a sequence of red, brown, and
black interbedded Jatite, andesite, and basalt flows and
pyroclastic rocks. The Table Mountain Latite includes black fine~
grained porphyritic basalt with small plagioclase phenocrysts;
light-red vesicular latite porphyry with large plagioclase
phenocrysts; and dark-red latite breccia. The Eureka Valley Tuff
consists of a series of moderately welded biotite augite lithic
tuffe with angular lithic and crystal fragments and abundant
flattened glassy streaks up to 5 cm long. K-Ar ages of 10.0 to 8.8
my- are reported by Noble and others (1974) for the Stanislaus
Group in adjacent quadrangles. The Stanislaus Group unconformably
overlies the Relief Peak Formation and is unconformably overlain by
the Disaster Peak Formation

LEVIATHAN PEAK ANDESITE (Curtis, 1951) (late Miocene(?)~early
Pliocene)~-Dark blue-gray, orangish-brown weathering,
platy-jointed, flow-banded porphyritic hornblende andesite flows
and shallow intrusions. Characterized by strong flow foliation
defined by subparallel alinement of plagioclase and hornblende
crystals and by hornblende phenocrysts which locally reach 5 cm in
Length

ANDESITE OF HAYPRESS FLAT (Miocene-Pliocene)—Medtum-gray to blue~
gray platy-weathering flow-banded porphyritic hypersthene-augite
andesite flows and shallow intrusions. Locally vesicular with
tridymite partially filling vesicl Flow foliation defined by
parallel alinement of 1- to 3-mm long plagioclase laths. May be
correlative with the Leviathan Peak Andesite

ANDESITE OF BAGLEY VALLEY (Miocene-Pliocene)—Poorly exposed blue-
gray platy-weathering flow-banded porphyritic hornblende-augite-
hypersthene andesite flows and shallow intrusions.  Hornblende
crystals are characterically totally altered to fine-grained opaque
minerals. May be correlative with the Leviathan Peak Andesite

QUARTZ LATITE PORRPYRY (Wachter, 1971) (Miocene)--White to dark-gray
locally flow banded quartz latite porphyry. Contains 20 to 30
percent phenocrysts of plagioclase, hornblende, biotite, quartz,
and augite set in a very pale brown glass. Includes flows, flow
preceias, and shallow intrusions. Intrusive into the Relief Peak
Formation and overlain by the Leviathan Peak Andesite

OLIVINE BASALT (Miocene?)--Light-gray finely porphyritic flow-banded
olivine basalt. Contains 1 to 2 percent small (<I mm) olivine
phencerysts in an aphanitic groundmass. Unconformably overlies the
Relief Peak Formation. May be part of Wilshire’s (1957) Tryon Peak

Flows

SILIFICIED ROCK (early Pliocene?)--Includes red, brown, and yellow
“porous quarte-pyrite jasperoid, dense gray quartz-pyrite jasperoid,
dense blue chalcedony-pyrite jasperoid, dense white quartz
jasperoid, and dense white opal. Replaces volcanic tuffs, flows,
‘and flow breccias of the Relief Peak Formation. Volcanic textures
commonly preserved

INTRUSIVE RHYOLITE (early Pliocene?)--White to pale-reddish—brown
flow-banded sparsely porphyritic quartz sanidine rhyolite.
Contains 2 to 5 percent quartz or cristobalite, sanidine, and
locally, biotite phenocrysts (0.5-2 mm long) in an aphanitic or
micrerystaiiine groundmass. Consists of 8 emel) plugs intruding
massive andesite flows and flow breccias of the Relief Peak
Formation. Associated with hydrothermal alteration and Au-Ag
mineralization at the Zaca mine on Colorado Hill. Morton and
others (1977) report K-Ar ages of 4.760.19 my. (whole rock) and
4.95£0.24 mey- (sericite) for altered thyolite from Zaca mine

INTRUSIVE ANDESITE (Miocene?)--Includes a dark-gray porphyritic
hornblende andesite body about 3 km north of the Leviathian mine
containing 12 to 15 percent, 2 to 8-mmlong hornblende

a small porphyritic augite andesite body about 3 km
southwest of the: Leviathan mine; and a dark-gray vesicular
porphyritic hornblende andesite about 3 km south of Moniter Pass
locally containing sparse quartz xenocrysts and 0 to 5 percent
quartz-epidote amygdules

DACITE (Miocene?)--White, gray, black, and reddish-brown flow-banded
porphyritic biotite-augite-hornblende dacite flows, flow breccias,
and intrusions exposed in the north-central part of the
quadrangle. Consists of 10 to 20 percent phenocrysts of
plagioclase, hornblende, avgite, biotite, and hypersthene(in
decreasing abundance) set in pale-brown glass. Intrusive into and
overlying lahars of the Relief Peak Formation

INTRUSIVE DACITE (Miocene(?)-Pliocene)-~Includes a dark-gray
porphyritic hornblende dacite porphyry on Wild Oat Mountain
containing 7 to 10 percent hornblende, plagioclase, and quartz
phenocrysts in a microcrystalline quartz-feldspar matrix and a
white to blue-gray hornblende dacite porphyry approximately 2 km
northwest of Wolf Creek Meadows containing approximately 20 percent
hornblende and plagioclase phenocrysts (1-3 mm long) and sparse
quartz phenocrysts in a cryptofelsite groundmass

MINEHAHA ANDESITE (Noble, 1962) (Miocene?)--Chalky green, lavender,
‘and red, porphyritic augite andesite, hornblende andesite, and
dacite flows exposed in the extreme northeast corner of the
quadrangle. locally propylitized

flow, biotite-hornblende andesite flows, and minor volcaniclastic
sandstone and conglomerate. Stippled areas are composed primarily
of dark-orange-brown-weathering andesitic lahars. Locally strongly
propylitized and locally silicified. Includes Early Andesitic
Vol: x12 and Markleeville Autobrecetated Flows (in part) of Curtis
(1951) and Goskey Canyon Andesites and Markleeville Volcanics of
Wachter (1971). K-Ar ages of 9540.3 my. (biotite) and 9.70.4
m.y. are reported by Morton and others (1977) for a biotite-
hornblende andesite flow near the Morningstar mine

TOPAZ LAKE PORFHYRITIC QUARTZ MONZONITE (Curtis, 1951) (Late
Cretaceous)~-Light-gray to‘white mediumgrained porphyritic biotite
granite to granodiorite characteristically containing 5 to 35
percent, 2 to 10 cm pink microcline perthite megacrysts and 0 to 5
percent fine-grained ragged biotite crystals. Includes minor
pegnatitic and mediumgrained alaskitic border phases. A biotite
K-Ax age of 82.1 my. is reported by Evernden and Kistler (1970)
for @ sample collected along Wolf Creek

GRANOMIORITE OF THE CHINA GARDEN PLUTON (Schweikert, 1976) (Late
Cretaceous)--Pinkish-gray to white mediumgrained seriate,
hornblende-biotite granite to granodiorite containing approximately
2 percent anhedral hornblende and 5 percent anhedral biotite.
Includes porphyritic, granophyric, and foliated border phases. R-
Kistler (oral coumun-, 1980) reports a whole-rock Rb-Sr isochron
agelof 92.142.7 my-

METADACITE (Schweikert, 1976) (Late Cretaceous?)--Dark-gray fine-
gtajned schistose metadacite welded tuff containing 15 to 20
pergent broken plagioclase crystals and locally abundant 1- to 3-mm
clogs of fine-grained biotite. Intrudes and overlies
metérhyolite. May be an. extrusive phase of the China Garden pluton
(Schweikert, 1976)

DOUBLE SPRINGS FORMATION (Noble, 1962) (Upper Jurassic-Cretaceous)—
Rhyglitic to andesitic flows, flow breccias, and tuff breccias with
intérbedded volcaniclastic sandstone, conglomerate, and minor
Liméstone metamorphosed to lower greenschist facies. Unconformably
oveglies the Preachers Formation

PREACHERS FORMATION (Noble, 1962) (Lower Juraseic)--Well sorted fine
grained lithic arenite and wacke metamorphosed to lower greenschist
facies. Unconformably overlies the Gardnerville Formation

GARDNERVILLE FORMATION UNDIFFERENTIATED (Noble, 1962) (Upper
‘Tripasic?-Lower Jurassic)-—Includes intermediate to felsic volcanic
conglomerate with lesser volcanic sandstone and siltstone,
cetpovatenveleanic clast conglomerate, limestone, black pyritic
marine siltstone and intermediate tuffs metamorphosed to lower
geebpschist facies

METARHYOLITE (Schweikert, 1976) (pre-Late Cretaceous)--Chalky vhite,
brown  co-—s orange-weathering fine-grained —schistose,
blastoporphyritic metarhyolite. Breccia textures are locally
preserved. Intrusive into the West Antelope Sequence

WEST ANTELOPE SEQUENCE (Schweikert, 1976) (Lower Jurassic?)--Dark-
broym to black fine-grained tuffaceous sandstone, and siltstone
interbedded with minor conglomerate, limestone, and rhyolite
tuff(?).  Metamorphosed to greenschist facies schist, phyllite,

cof ot marble, and felsite. Biotite hornfels locally present

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contacts with the Topaz Lake Quartz Monzonite and the China

Garfien Pluton. Exact age is unknown but Schweikert (1976) suggests
a lower Jurassic age. May be correlative with the Gardnerville
Formation

F

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i REFERENCES

Curtis, G. H-, 1951, The geology of the Topaz Lake quadrangle and the eastern
half of ‘Hhbetts Pass quadrangle: Berkeley, University of California,
Ph. D. thepis, 310p.

Dalrymple, G.| Be, 1964, Cenozoic chronology of the Sierra Nevada,
California! California University Publications in Geological Sciences,
v. 47, 41 pe

Evernden, J. +, and Kistler, R. W., 1970, Chronology of emplacement of
Mesozoic Watholithic complexes in California and western Nevada: U.S.
Geological! Survey Professional Paper 623, 42 p+

Morton, J. L.,, Silberman, M. L., Bonham, H. F., Jr-, Garside, L. J-, and
Noble, D. €., 1977, K-Ar ages of volcanic rocks, plutonic rocks, and ore
deposits {n Nevada and eastern California-~determinations run under the
USGS-NBMG booperative program: Isochron/West, v- 20, p+ 19-29.

Noble, D. C-, .262, Mesozoic geology of the southern Pine Nut Range, Douglas
County, Nevada: Stanford, Calif., Stanford University, Ph. D. thesis,
200 p-

Noble, D. C., Slemmons, D. B., Korringa, M. Ke, Dickinson, W. R-, Al-Rawi, Y-,
‘and McKee, Ee H+, 1974, Bureka Valley Tuff, east-central California and

Geology, v- 2, p+ 139-142.

Shallow level intrusions in the eastern Sierra

Stanford, Calif-, Stanford University, Ph. D.

thesis, 85 p.

1976, ‘Shallow-level plutonic complexes in the eastern Sierra Nevada,
Californiz, and their tectonic implications: Geological Society of
America Special Paper 176, 58 p+

Slemmons, D- Bs, 1953, Geology of the Sonora Pass region:
University of California, Ph. D. thesis, 201 p+
1966, Cenozoic volcanism of the central Sierra Nevada, California:
California Division of Mines and Geology Bulletin 190, p. 199-208.

Stanford Geological Survey, 1964, Geologic map of the Antelope Valley area,
Mono County, California: Stanford University, unpublished mapping, scale
1:62, 500.

Streckeisen, A., 1976, To each plutonic rock its proper name:
Reviews, v- 12, p+ 1-33.

Wachter, B. G-, 1971, Rapid fresh and altered rock analysis for exploration
reconsissance: infrared absorption applications in the Monitor district,
California: Stanford, Calif., Stanford University, Ph. D. thesis, 115 p-

Wilshire, -H. G., 1956, The history of Tertiary volcaniem near Ebbetts Pass,
Alpine County, California: Berkeley, University of California, Ph. D.
thesis, 123 p.

____, 1957, Propylitization of Tertiary v leanic rocks near Ebbetts Pass
Hipine County, California: University ‘of California, Publications in
Geological Sciences, v- 32, p+ 243-272.

Berkeley,

Earth Scdence