Petroglyph Canyon Quadrangle

117¡ 45' 00'' 36¡ 07' 30'' 117¡ 37' 30'' Jsp Tbp 36¡ 07' 30'' † Tap EXPLANATION Td Ta Jsp Tap Qya Tbp Tbp COVER UNITS MAP SYMBOLS 90 Ta Tbp Jsp Jecg Tbp Ta Tap Jsp Jsp Ta Qya Younger Alluvium* Boundary of Quaternary rhyolite within coeval pyroclastic de posits; Tbp Jecg Qya tick marks face toward eruptive center Jsp Jsp Tbp 55 Tap Td 10 15 Qbd Basalt Southeast of Devils Kitchen* Tbp Ta Kcf 58 Boundary of probable landslide; tick marks localized along b ase of Tbp 55 slide block and face toward structural top Tcp 61 Tbp 35 Jecg 31

48 Quaternary 34 67 Qoa Older Alluvium* Ta Jsp cs Ta 78 Jecg 84 Kcf Approximate structural limit of tectonic breccia; tick marks localized Qya 58 65 along brecciated side of contact Tbp 41 Jecg QTbr Basalt of Renegade Canyon* Tcp Tbpp Kcf

Kcf 49 Tbp Fault contact; solid (known), dashed (approximate), dotted ( inferred), Tanp Andesite Northwest of Petroglyph Canyon, pyroclastic * Tcp Qya queried where conjectural. Ball and bar on down-dropped side of Tbp Tbp normal fault. Teeth on upper plate of thrust fault. Ta Tbp Tbp 47 Tan Andesite Northwest of Petroglyph Canyon* Tbp Tap Tc Kcf Tcp Jecg Tc Tcp Tbp Ta Tbp Tbp Ductile shear (mylonite) zone Tc Tbp Tbp Tcp Coso Formation, air-fall pumice Jsp * Ta Tc Tc Tbp Tbp Ta Jecg Tc Coso Formation, fanglomerate* Ta Tbp Qya Tc Tbp Tbp Kcf Tc Kcf Kcf Intrusive or depositional contact; solid (known), dashed (ap proximate), 24 short dash with query (inferred) Ta Tt Tuff Southwest of Volcano Butte* Tcp 34 Tbp 27 17 22 32 Tc Qya 16 Jecg Jecg Tc Qoa 41 Tdyp Younger Dacite East of Coso Hot Springs, pyroclastic * Tc Tbp 42 Jecg Tbp 17 22 Tdy Younger Dacite East of Coso Hot Springs* 31 Jsp Kcf Tc Tc Jecg Qya Tc Qya Tdop Older Dacite East of Coso Hot Springs, pyroclastic * Qya Tc Tc 68 Tdo Older Dacite East of Coso Hot Springs* Qya 30 Fold axis; syncline, anticline, doubly-plunging syncline Qya 87 Tc Tertiary Tbp 11 Jecg 14 76 Tbp Tbp Tbp Tbpp Basalt of Petroglyph Canyon, pyroclastic* 63 Strike and dip of bedding plane; inclined Qya Tbp Tcp Tbp Tc Qya Qya Tc Tbp Basalt of Petroglyph Canyon* 76 Tbp Tc Jecg Strike and dip of flow foliation; inclined, vertical Tc 49 Tdo 44 Qoa Tbp Tbcp Basalt of Coso Peak, pyroclastic* Qya 44 13 Qoa 38 74 Strike and dip of fault plane; inclined, w/ down-dip lineati on, Tbp 58 Tbp 32 w/ horizontal lineation, w/ oblique lineation, subhorizontal Jecg Basalt of Coso Peak Tbp Qya Tbc * lineation Tdo Qya Tc Tbpp

Tbp 80 Strike and dip of fracture cleavage; inclined, vertical Tdo Qya Tdop Jecg Jecg Tdop Tmp Mafic Rocks, pyroclastic* Tdo Jecg Tm Tc Qya Tm Mafic Rocks* 58 Tdo Qya Tm Strike and dip of joint plane; inclined, vertical Jecg Tc Tcp Tbp Tbp 35 Tc Jecg Tm Tap Andesite, pyroclastic 21 Strike and dip of foliation/compositional layering; inclined , * 48 Qya 81 vertical, w/ down-dip lineation, w/ horizontal lineation, Tm 17 Tc w/ oblique lineation Tbp Tcp Ta Andesite*

Locality of sample used for radiometric age determination. Tc Tbp Tm Tm

Tdyp Tdp Dacite, pyroclastic*

Qya Td Dacite* Qoa Tbp Tdy Tdy Tbp Qya cs,m Tan Tbp Jecg

Tan Tbp Tbp Tcp BASEMENT UNITS Tc Tanp Tanp Tdy Tanp 43 Tbp Tcp Tbp Kcf Leucogranite of Cactus Flats {Alkali-feldpar Granite} [102±4 Ma] Tc Tbp Tmp Cretaceous Tan Tm Qya Tmp Tbp Jecg JKdi—Independence Dike Swarm (red: felsic, green: mafic–inte rmediate) [166±1 to ~119 Ma] Tcp Tbp Tcp Tc Tan Tan Tbp Jecg Tan Tbp Tan Qya Tm Tan Tc Jecg Qya Jmci Mixed Complex, intermediate component {Quartz monzodiorite} to {Diorite} [150±1 Ma] Tm 63 q Tm Tan Tcp Tbpp Tbpp Tcp Tbp Tbp Tcp Jmci? Tan Tm Qya Qya Jsp Silver Peak Pluton {Quartz Monzonite} to {Granite} [158±1 Ma ] Tan Qya Qya Tbp Tbp Jurassic Tm Qya 45 Tm 32 Tm Tan Tbp Tbp Tbp Jecg Intrusive Complex of Eastern Coso Range, granitoid rocks [>1 66 Ma] Tbp Tan Qya Tc Tbp Tc Jmci? Tcp Tbp Tan Td Tbp Qya Tm Mzb Basement Rocks* Tan Td Tan Tm Tan Tbp Tbp Tmp

Td PzÐMz cs, etc. Metamorphic Rocks of Uncertain Age (see Chapter One for deta ils) Tm Td Qya Qya Tm Tbp Qya Tm Tbp Tm Jmci? Tan Tmp Tbp Qya Tbp Qya Tmp Td Td Qya Tbp Tmp Td Td Tbp QTbr1 Td † Units listed represent only the geologic column for this qua drangle. The geologic column for the entire Coso Range, incl uding description of the radiometric ages cited here, is lis ted within the text Tm Qya file on this CD. Units highlighted with an asterisk ( *) were defined and described by Duffield & Bacon (1981). Map symbols shown represent the complete set of symbols used in this study. Some Qya of those illustrated may not be relevant to the geology of this particular quadrangle. Qya Tm Td Tbp Td Qya Tbp Tbp Td Tbp Tbp Tbp Td Td Tm Qya

Qya Td Tt Tbp Tap Tbp Tcp Mzb Qoa Ta Qya Ta Ta Tap Tbp Tbp Tcp

Qoa Ta Td Tm Tbp Tap Tbp Tcp Td Qoa Tap Td Tap Tap Tcp Qbd Qoa Tbp Tap Tap Td Ta Td Tdp Qoa Qya Ta Qoa Td 36¡ 00' 00'' Ta Ta Td 117¡ 45' 00'' 36¡ 00' 00'' 117¡ 37' 30'' GEOLOGIC MAP OF THE PETROGLYPH CANYON 7.5' QUADRANGLE;

118¡ 00' W 117¡ 45' W 117¡ 30' W INYO COUNTY, CALIFORNIA

Talc Vermillion Centennial City Canyon Canyon Darwin Hills Total map area of Whitmarsh (see reference map) includes som e contacts and unit labels A Compilation by Richard S. Whitmarsh established by Stinson (1977) and Duffield & Bacon (1981). C ontacts within the Cenozoic 36¡ 15' N 1997 cover sequence either copied or adapted from Duffield & Baco n (1981). Structural data and Upper Haiwee Coso China Centennial contacts within the pre-Cenozoic basement complex, except wi thin unit Mzb, established Reservoirs Peak Gardens Flat by Whitmarsh 1994-1996.

References Cited:

Coso Cactus Petroglyph Louisiana ArcInfo¨ coverage Junction Peak Canyon Butte Duffield, W.A. and Bacon, C.R. 1981. Geologic map of the Cos o volcanic field and adjacent areas, B Inyo County, California. U.S.G.S., Miscellaneous Investigat ions Series, Map I-1200. 36¡ 00' N Stinson, M.C. 1977. Geologic map and sections of the Keeler 15-minute quadrangle, Inyo County,

Mountain California. California Division of Mines and Geology, Map S heet 38. Little Volcano Airport Springs Lake Peak Lake Canyon SCALE 1:24,000 CONTOUR INTERVAL 20 feet A. Stinson (1977): dotted outline Magnetic North B. Duffield & Bacon (1981): dash-dotted outline UTM Grid North (about 15¡ east) Ninemile White Burro 0 1 2 3 Pearsonville Canyon Hills Canyon Geographic North (about 0.5¡ east) 35¡ 45' N Kilometers Reference map with 7.5 minute quadrangle boundaries. Red lin e delineates 0 1 2 boundary of ArcInfo¨ coverage compiled by Whitmarsh during 1994-1997 at the University of Kansas: Department of Geology: Structur al geology and GIS laboratory. Shaded areas (A and B) encompass portions of earlier Miles geological maps containing contacts that have been included in this compilation. Bold black line highlights the locality and boundary of this quadrangle. Topographic base: PETROGLYPH CANYON 7.5' QUADRANGLE (USGS, P ROVISIONAL EDITION 1982)