BULLETIN 612 



SHEET No. 12 



GEOLOGIC AND TOPOGRAPHIC MAP 



OF THE 



OYERL A^^D EOUTE 



From Omalia, Nebraska, to San Francisco, California 



Base compiled from United States Geological Survey Atlas Sheets, 

 from raili'oad alignments and profiles supplied by tlie Union Pacific 

 Railroad Company and tlie Southern Pacific Company and from addi- 

 tional information collected with the assistance of these companies 



UNITED STx\TES GEOLOGICAL SURVEY 



GEORGE OTIS SMITH, DIRECTOR 



David White, Chief Geologist 



B* B, Marshall, Chief Geographer 



1915 



Each qrjadrangk shown ok the map with a name in parenihssis in the 

 lower left comer fs mapped in detail on the U. S. G. 5. Topographic 

 sheet of thai name. 



WYOMING 



re: AT CIV I 



BASIN 



Tertiary 



N SHOWING FOftMATtONS CROSSED BETWEEN HILLSIDE AND ROCK SPRINGS 



EXPLANATION 



Sandstone, shale, and coal; fresh-water 

 deposits (Wasatch group and Green Rivor 

 formation of White Mountain) 



Sandstone, shale, and coal; fresh and brackish 

 water deposits ("Lower Laramie", Black 

 Buttes coal proup) 



Shale; marine deposit (Lewis shale) 



Sandstone, shale, and coal; brackish and 

 fresh-water deposits (Mesaverde formation) 



Shale; marine deposit (includes etjuivalent of 

 Steele shale) 



Thickness 

 in feet 



Tertiary 



2.300 

 750 



5,000 



Cretaceous 



BASIN 



