GEOLOGIC AND TOPOGRAPHTO MAP 



OF THE 



OVEKLAND ROUTE 



From Omaha^ Nebraska, to San Francisco, California 



Base eompUecl from United States Geological Survey Atlas Sheets, 

 from railroad alignraentR and profiles supplied by the Union Pacific 

 Railroad Conipan:/ and the Southern Pacific Company and fronj addi- 

 tional information collected with the assistance of these companies 



UNITED STATES GEOLOGICAL SUEYEY 



GEORGE OTIS SMITH, DIRECTOB 



David White, Chief Geologist 



R» B. Marshall, Chief Geographer 



1915 



Bach quadrangle skoum en the map un'th a name in parenthesis in the 

 fewer left comer is mapped in detail on the U. 5. G, S, Topo^cphic 

 sheet of that name. 



EXPLANATION 



♦ ♦Tpt+J Pinole tuff 



P&bto 



malion 



Briones 

 sandstone 



Hercules shale 

 member 



Rodeo shale 



\UMlM sandstone 

 tdljLA Cretaceous ^^: 



'I 



zMiles 



FIGURE 19 -MAP SHO'/«/INe GOXOeiC rcnMATiONS AL0N6 THESOUTh 

 SW. 



OF SAN P^BLO BAY. 



&4 



Th 





• ' 



^;^i^NS^;: 



>c 



• % 







1 



w 



o 



-A, 



.Mile 



flSUnZ EO-SECnON showing structure along the south shore of SAN PABLO BAY 



BULLETIN 612 



I 



IZ5 



EXPI-\NATION 



deposits 



resh-water gravels, sands, and clays (Santa Clara for-1 

 mation, early Quaternary and Pliocene); marine clay, I 

 sandstone, and conglomerate (Merced formation, Plio-] 

 cene) ; and stratfied lig:ht -colored pumice (Pinole tuff, I 



Pliocene; 



Light-colored 

 shale (San 

 Miocene 



soft sandstone and chalky bituminous^ 

 Pablo formation and Monterey group); 



Hard sandstone above (Tejon formation); chiefly con- 

 glomerate with sandstone ; some shale and thin lime- 

 stone 1 Martinez formation) below; Eocene 



Lava flows (basalt and rhyolite) 



Massive yellowish sandstone with conglomerate member 

 below tChico formation. Upper Cretaceous), underlain 

 by calcareous and arenaceous shale (Knoxville forma- 

 tion, Lower Cretaceous) 



Chiefly intrusive rocks (basalt, diabase, gabbro, perido- 

 tite, pyroxenite, serpentine); Jurassic (?) 



Sandstones with subordinate shales, locally alternating 

 with varicolored radiolarian cherts and some limestone : 

 local schists due to metamorphism on contact of 

 igneous rocks (Franciscan group); Jurassic (?) 



Granite (quartz diorite) 



Scale 



500.000 



Approximately 8 miles to 1 inch 



SHEET No. 25 



IZ2 3D* 



CALIFORNIA 



Quaternary 



Quaternary 

 and Tertiary 



^/w 



y^.". 



■^ ■ T.'-^ 



E'verano 



^"^t:^ 



Tertiary 



Burden MTr> 



0^ 



Mesozoic 



.^«^ 



ova- 



Taylorvill 



Pre-Jurassic (?) 





SdKom* 



helTviHei-A r 



PABLO 



p;,^ ^s 



MARE ISLAMD 

 NAVY VA R D 



VaileioJjr.ctioii;&;^i^'^^ 



■^T?: 



'<^i' 



t'^*^: 



■» ' 



•=^>V; 



i\ 



.1- 



n 



■-^j 



^:^*^ 



8»y 



-* 



anQuen 



Pt Bon.i 





Fort Pt 



CI iff House 



SAN FRANC 



(San francos- 



^ 



X 



I 



lO 



■ ' ^ ' ■ ' 



15 20 



'■■'■'' 



2oM!les 

 3oKilcmeters 



Oce 



Contour interval 200 feet 



WLEVATIONS IN FEET ABOVE MEAN SEA LEVEL 



The distances from Omaha, Nebraska, are shcum every 10 miks 

 The crossties on the railroads are spaced J mile apart 





\o\ 



1 



a—.. 



.lameda ; 



here 



E:tacion * ^ 



Sanirsncisco 



ot 



^^■z-o 



runo 



Ibr. 



!0 



