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Framework Geologic Map and Structure Sections Along the Bartlett

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Framework Geologic Map and Structure Sections Along the Bartlett U.S. Department of the Interior Scientific Investigations Map 3395 U.S. Geological Survey Sheet 2 of 2 Pamphlet accompanies map CORRELATION OF MAP UNITS 123°15' 123° 122°45' 122°30' A B EXPLANATION 39°45' EXPLANATION Nonmarine basin deposits (Quaternary) CASSZ [See Description of Map Units (in pamphlet) for precise unit ages] 1 NBSFZ PLASKETT Ohlin and others, 2010 Klamath 5 Eureka Volcanics and deposits of Clear Lake area MEADOWS 2 Berkland, 1978; CDWR, 1966, 1968, and 1969 block FUTURE NBSFZ (Holocene–Pliocene) UNCONSOLIDATED DEPOSITS DOS RIOS THATCHER PLASKETT RIDGE RIDGE 3 McLaughlin, R.J., unpublished mapping, 1980–1981 JAMISON RIDGE 6, 15 MFZ Eel River forarc basin (Neogene) 5, 27 4 McLaughlin and others, 1990 Round NSAFZ Crystalline basement rock 5 Jayko and others, 1989; Clark, 1940 Coastal Belt ALLUVIAL TERRACE FAN GLACIAL SPRING VOLCANIC 5, 18 Valley 6 Ohlin H.N., 1989, unpublished mapping, 1985 DEPOSITS DEPOSITS DEPOSITS DEPOSITS DEPOSITS ROCKS Western Transverse Ranges block 7 Hitchcock, C.S., unpublished mapping, 2012–2013; McLaughlin, NBSFZ 21 FELKNER R.J., and Moring, B.C., aerial reconnaissance using Google Earth MAAFZ Central Belt (Upper Cretaceaous and older) SANHEDRIN 1 HILL 5 BRUSHY imagery, 2014 Wilber Springs WILLIS RIDGE MOUNTAIN MOUNTAIN HULL MOUNTAIN Eastern Belt (Upper Cretaceous–Upper Jurassic) KNEECAP RIDGE 8 Etter, 1979; U.S. Forest Service, unpublished mapping Dextral Hook af Qty Qfy Holocene AREA OF 6, 15 MAP 9 Northern Sierra Nevada block Stanford, 1991 Salinian block Coastal Belt (Tertiary and younger) 1 Santa 10 Berkland, 1973 RC-HLDFZRosa Qls Qgd 39°30' Coast Range ophiolite and ophiolitic mélange Qal QUATERNARY 11 Hearn and others, 1995; Sims and Rymer, 1976; Rymer, 1981 Reconstructed 2, 16, LAKE NSAFZ (Lower Cretaceous and Upper–Middle 12 Brown and others, 1981; MacPherson, 1983 Bartlett Springs Qt Qf Qfo 18 18 PILLSBURY Jurassic) Qto synform Qoa 1 12, 13 13 Brown, 1964 FUTURE NBSFZ Qv San Francisco HAY-CAFZ SYMBOLS Pleistocene FOSTER VAN ARSDALE CROCKETT SAINT JOHN STONYFORD 14 Suppe and Foland, 1978; Etter, 1979; U.S. Forest Service, PEAK MOUNTAIN 31-90° MOUNTAIN 2 RESERVOIR unpublished mapping Upper Cretaceous—Neogene clockwise rotation in ? ? 1 15 Qtvo Qfvo Blake and others, 1992 southern Sierra Nevada Batholith and Qsn Qtrv 8 12, 18 25 16 McLaughlin, R.J. and Moring B.C., mapping 2012–2013 Tehachapi Mountains block (Chapman and ? ? 17 Ohlin, H.N., unpublished field work, 1980–1981 others, 2010) FLUVIAL AND LACUSTRINE FILL POTTER 18 McLaughlin and Moring, aerial reconnaissance using Google Earth SAFZ Approximate location of buried tip of Franciscan Monterey 0 10 20 30 KILOMETERS VALLEY 8 imagery, 2012–2014 7 1 tectonic wedge—Barbs on roof thrust side of Pleistocene QUATERNARY 10 FOUTS SPRINGS GILMORE LODOGA 19 Ohlin, H.N., unpublished mapping, 1979–1981 QTc ELK POTATO PEAK 0 5 10 15 MILES wedge Salinian block and Pliocene AND TERTIARY REDWOOD MOUNTAIN 8, HILL 20 McLaughlin, 1978; Ohlin H.N., and McLaughlin, R.J., unpublished VALLEY 12, 13 mapping, 1978–1981 Fault—Arrows show relative movement 16 Southern Sierra MARINE OVERLAP DEPOSITS 9 14, 18 21 Lehman, 1974 Nevada/Tehachapi 39°15' Thrust fault block 22 McLaughlin, R.J., and Moring B.C., minor revisions WW-KCFZ Bakersfield CENOZOIC 2 Tm Miocene 18 23 Lawton, 1956 31-90° Vectors of maximum compression—From 24 Swe and Dickinson, 1970 SG-HFZ orientation of fold axes COW UPPER BARTLETT BARTLETT GARFZ UKIAH HOUGH SPRINGS LEESVILLE Mojave block MOUNTAIN LAKE MOUNTAIN SPRINGS 25 Shervais and others, 2005a, b MAJOR FOLD AXES Te Eocene 3, 16 4, 16, 18 26 Lienkaemper, 2010 18 Antiform 14, 16 27 Clark, 1940 Western Transverse SAFZ Tep Ranges block (present) Synform SALT San Gabriel Tcg 7, 17, 18 CANYON Mountains block 5 Ma 11 4, 16, 18 CLEARLAKE 0 50 100 150 KILOMETERS TERTIARY LAKEPORT 11 LU- BENMORE WILBUR SPRINGS COAST OAKS CANYON 10 Ma LUCERNE 4, 16, 18 0 25 50 75 MILES 15 Ma RANGE 26 GREAT VALLEY COMPLEX OPHIOLITE FRANCISCAN COMPLEX 18 Eocene and 11, 7, 11 39° Paleocene 22 CENTRAL BELT EASTERN BELT 11 CLEARLAKE WILSON Figure 8. Map showing Wilbur Springs Dextral Hook in context of regional structure by northward translation of the Salinian block since the early to middle Miocene. HIGHLAND LOWER Central Belt Mélange Terrane KELSEYVILLE HIGHLANDS VALLEY 23 Rice Valley ELDER CREEK TERRANE SPRINGS 11 LAKE and long-term transpressional deformation along the Northern Bartlett Springs Fault Upper Cretaceous–Paleogene rotations in southern Sierra Nevada-Tehachapi block, ? 19, 20 3, 24 Zone. A, Partial map of California, showing major fault blocks associated with east-vergent crustal wedging, and unroofing of the Franciscan Complex Pomo GLASCOCK 20 Miocene and younger development of the San Andreas Fault, northwestward accompanied shallow subduction of overthickened Farallon Plate and was followed Terrane 3 MOUNTAIN Marin Snow Pickett Peak Mendocino translation of Salinian block, clockwise rotation of Western Transverse Ranges block by northward translation of the Salinian block during the Miocene (Chapman and fcm Headlands- Mountain spo Yolla Bolly Terrane Terrane Pass Terrane (Colgan and others, 2012), and Upper Cretaceous–Neogene clockwise rotation of others, 2010, 2012; Saleeby, 2003; Ernst and McLaughlin, 2012). See text for further b Volcanic c ? Geysers Figure 2. Map showing quadrangles in map area and sources of geologic data. southern Sierra Nevada /Tehachapi block (Chapman and others, 2010). White box discussion. Fault abbreviations: CASSZ, Cascadia Subduction Zone; GARFZ, Garlock ss Terrane Terrane outlines Wilbur Springs Dextral Hook. B, An expanded view of Wilbur Springs Dextral Fault Zone; HAY-CAFZ, Hayward-Calaveras Fault Zone; MAAFZ, Maacama Fault Kuls db Late Hook derived from figures 6 and 7, showing reconstructed Bartlett Springs Synform Zone; MFZ, Mendocino Fault Zone; NBSFZ, Northern Bartlett Springs Fault Zone; ms un Ku Cretaceous and other folds of the dextral hook. Orientations of folds suggest maximum NSAFZ, Northern San Andreas Fault Zone; RC-HLDFZ, Rodgers Creek-Healdsburg cgl v ? ? cgmg uny fym vy compression was ~N. 41° E. to S. 41° W., ±16°. Geometry and approximate timing of Fault Zone; SAFZ, San Andreas Fault Zone; SG-HFZ, San Gregorio-Hosgri Fault Zone; ? smg by cgy cy mspy Wilbur Springs Dextral Hook formation is similar to larger-scale dextral hook formed WW-KCFZ, White Wolf-Kern Canyon Fault Zone. gy lsy ? ? ? fys ? ? ? ? ssm miy oms omv omd psm ? Klcg omg omc omb omun vsm fpp cpp CRETACEOUS SOUTHWEST NORTHEAST vpp ? Kul Kl KJom A A' NORTHWEST SOUTHEAST FEET FEET C–C' dsm Early 6,000 NORTHERN BARTLETT SPRINGS v fcm 6,000 B’–B” c fcm E SECTION SECTION E' Cretaceous v FAULT ZONE Qls fys Qls Qfy QtyQt fpp FEET FEET 4,000 fcm Qls Qal 4,000 Qtvo fys KJom? Qal Josp 4,000 Qal Qal Qal Qal fym fys 4,000 Little Indian Qoa Qt fys? fys Tep Kul Qal KJom ssm ? KJom? Qfo Valley 2,000 2,000 2,000 2,000 ? ? fmp cmp ? KJom fpp Klls SEA LEVEL fys SEA LEVEL SEA LEVEL SEA LEVEL ? ? Kul fym 2,000 fys 2,000 fcm Kssp 2,000 fcm fcm 2,000 fys fym ? 4,000 4,000 4,000 fys 4,000 KJs ? fcm 6,000 6,000 6,000 fym 6,000 fcm _ + ? NORTHERN BAR 8,000 8,000 8,000 TLETT + 8,000 SPRING fcm S FAULT ZONE 10,000 10,000 10,000 _ 10,000 12,000 12,000 12,000 12,000 Jgb MESOZOIC ? ? Late cy cmg Jurassic SOUTHWEST NORTHEAST B' Snow Mountain B E–E' B'' FEET Qgd FEET SECTION vsm 6,000 Qls Qgd 6,000 BEND IN SECTION Qal Qtvo vsm fpp Josp fcm? vsm fys Tep 4,000 fys KJom Josp Josp Josp KJs 4,000 cmg c b Ku fcm fym Qty Qfo Qfo Qls Qls fys vsm fys Josp Kl Ku Tep fys Qls Qal Qt Qal fcm Qfo Qfvo vmg Josp 2,000 Qfo Qal Qfy KJom Jov fys Qfo Qty 2,000 Kul fcm fys fcm SEA LEVEL Kl fym SEA LEVEL Joc vpo JURASSIC fym cmg KJs? 2,000 Josp 2,000 4,000 4,000 vpo 6,000 spo _ + 6,000 8,000 NORTHERN BARTLETT SPRINGS 8,000 FAULT ZONE Middle 10,000 10,000 Jurassic Jov SOUTHWEST NORTHEAST Jod PACIFIC RIDGE Jog C C' E–E' ANTIFORM Josp FEET NORTHERN BARTLETT FEET ? MIDDLE MOUNTAIN SECTION fys ? 6,000 SPRINGS FAULT ZONE fym vy Qal 6,000 ? SYNFORM fym vy vy Early Lower Blue fym fys 4,000 fys KJom vy 4,000 vy Lake smg Ku QtyQfy fys fys cy Josp Qt Jurassic Josp spo Kl v fys Qal Qfy Qal Qfo Qty fcm Qls Qal Qal fys Jov Qal Qto Qal 2,000 Qal Qfo Qty Qfo Qt Qty Josp KJs 2,000 vmg ? ? SEA LEVEL fpp SEA LEVEL ? vpo Josp ? 2,000 ? 2,000 fcm ? fcm ? ? ? 4,000 4,000 fcm 6,000 + 6,000 _ 8,000 8,000 LIST OF MAP UNITS oms Undivided marine clastic rocks, commonly argillitic (Lower vy Metavolcanic rocks (Middle Jurassic, Aelenian or older) 10,000 10,000 See Description of Map Units (in pamphlet) for complete unit descriptions. Cretaceous and Upper Jurassic) mspy Metaserpentinite blocks or lenses 12,000 12,000 Some unit exposures on the printed or plotted map are too small to distinguish omd Diabase, mapped locally the color for unit identification. These units are labeled where possible, and 14,000 14,000 uny Unidentified blocks unlabeled units are attributed in the database. Note that many tiny units, primar- omg Gabbro, mapped locally ily blocks, are covered by symbols. fys Metasandstone and argillite, locally conglomeratic (Upper and omc Radiolarian chert, mapped locally (Upper Jurassic, Kimme- Lower Cretaceous, Cenomanian to Aptian, to Late Jurassic, SOUTHWEST NORTHEAST UNCONSOLIDATED DEPOSITS ridgian) Tithonian) PACIFIC RIDGE af omb Blueschist, mapped locally ANTIFORM Artificial fill (Holocene) cy Metachert (Lower Cretaceous, Albian to Aptian, to Middle D NORTHERN BARTLETT SPRINGS D' Jurassic, Aalenian) FEET MIDDLE MOUNTAIN FAULT ZONE fym FEET Qls Landslide deposits (Holocene and Pleistocene)
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