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Geologic Map of the San Francisco - San Jose Quadrangle



Geologic Map of the San Francisco - San Jose Quadrangle


California Geological Survey, Regional Geologic Map No. 5A, 1:250,000 scale

Compilation by D.L. Wagner, E.J. Bortugno, and R.D. McJunkin

1991

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DESCRIPTION OF MAP UNITS

Alluvium
Artificial fill
Dredge or mine tailings
Intertidal deposits (Peaty mud)
Dune sand
Patterson Alluvium
Dos Palos Alluvium
Alluvial fan deposits 
Landslide deposits
Terrace deposits
San Luis Ranch Alluvium
Continental and marine deposits
Modesto-Riverbank Formations Undivided (Arkosic alluvium)
Modesto Formation
Riverbank Formation
Older alluvium
Turlock Lake Formation
Los Banos Alluvium
North Merced Gravel
Tulare Formation
Merced Formation
Plio-Pleistocene nonmarine deposits
Laguna Formation
Tehama Formation
Basaltic rocks
Lawlor Tuff
Purisima Formation
Tassajara Formation
Santa Cruz Mudstone
Santa Margarita Sandstone
San Pablo Group
Contra Costa Group
Fanglomerate
Monterey Formation
Pinole Tuff
Bald Peak Basalt
Page Mill Basalt
Miocene volcanic rocks
(Mva-andesite; Mvb-basalt)
Dacite
Mindego Basalt
Table Mountain Latite
Tertiary Volcanic rocks
Tvb - Tertiary Basalt
Lompico Sandstone
Lambert Shale
Temblor Formation
Undivided Tertiary marine sedimentary rocks
Mehrten Formation
Valley Springs Formation
Vaqueros Sandstone
Kirker Formation
San Lorenzo Formation
Poverty Flat Sandstone
Kreyenhagen Formation
Markley Sandstone
Nortonville Shale
Butano Sandstone
Domengine Sandstone
Meganos Formation
Ione Formation
"Auriferous" Gravels
Unnamed Eocene marine rocks
Tesla Formation
Locatelli Formation
Pt. Reyes Formation
Martinez Formation
Tertiary-Cretaceous marine sedimentary rocks
Pigeon Point Formation
Cretaceous volcanic rock
Chico Formation
Moreno Formation
Upper Cretaceous marine sedimentary rocks
Sandstone
Shale
Panoche Formation
Berryessa Formation
Lower Cretaceous marine sandstone and shale
Upper Jurassic-Lower Cretaceous marine sandstone and shale
Franciscan Complex
(* Horizontal line pattern denotes melange terrane)
Greenstone
Sandstone, shale, conglomerate
Metagraywacke
Limestone
Chert
Serpentinized ultramafic rock
Blueschist blocks
Coast Range Ophiolite
Rhyolite of uncertain age
Lotta Creek Tuff
Volcanic rocks, mainly basalt
Gabbro and diabase
Ultramafic rocks
Cretaceous granitic rocks
Cretaceous quartz diorite
Granitic rocks
Dioritic rocks
Gabbroic rocks
Ultramafic rocks

Mariposa Formation
Salt Springs and Merced Falls Slates
Jurassic (?) metasedimentary rocks
Jasper Point Formation
Metamorphic rocks of uncertain age
Copper Hill Volcanics
Logtown Ridge Volcanics
Gopher Ridge Volcanics
Penon Blanco Volcanics
Jurassic metavolcanic rocks
Metamorphic rocks of uncertain age
Metasedimentary rocks
(* Horizontal line pattern denotes melange terrane)
Metavolcanic rocks  (* Horizontal line pattern denotes melange terrane)
Gabbro
(* Horizontal line pattern denotes melange terrane)
Crystalline limestone and dolomite
(* Horizontal line pattern denotes melange terrane)
Ultramafic rocks
Calaveras Complex
Shoo Fly Complex
MAP SYMBOLS
Contact
Fault
Thrust fault
Blueschist blocks
Overturned fold
Strike and dip of beds
Strike and dip of overturned beds
Strike and dip of foliation
Anticlinal fold
Synclinal fold


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