. S. GEOLOGICAL SURVEY 



BULLETIN 707 SHEET No. 6 



GEOLOGIC AND TOPOGRAPHIC MAP 



RIO GRANDE ROUTE 



From Denver, Colorado, to Salt Lake City, Utah 



Compiled from United States Geological Survey atlas 

 sheets and reports, from railroad alinements and pro- 

 files supplied by the Denver & Rio Grande Western 

 Railroad Co., and from additional information col- 

 lected with the assistance of that company 



PREPARED UNDER THE DIRECTION OF 

 GEORGE OTIS SMITH, DIRECTOR 



EXPLANATION 



Age Thickn. 



B Gravel in river bottoma and terraces Quaternary 



F Red ahale and sandstone t Wasatch formadODl Tertiary (Eocene) 



H Sandstone, ahale, and coal beds (Meaaverde formation) ] 



J Dark marine shale (Mancos shale) ,' Upper Cretaceous 



M Brown sandstone ( Dakota sandstone) | 



N Variegated shale and sandstone (Gunnison formation) Cretaceous? 



and Jurassic 



P Brick-red massive sandstone Triassic 





X Granite 



Y Lava Sows 'basalt, andesite. latite, rhyoUte, : 

 tuff -breccia i 



Faalt 



Pre-Cambrian 

 Tertiary 



