U. 8S. GEOLOGICAL SURVEY BULLETIN 707 SHEET No. 6 
o. 
10730 ior COLORADO 
_ Scale 500,600 
Approximately 8 miles to | inch 
0 5 10 Miles 
Seea an ane ee Se Caen nna ence nieasiene | 
0 5 10 15 Kilometers 
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 
DAVID WHITE, Chief Geologist Cc. H. BIRDSEYE, Chief Topographic Engineer 
Elevations in feer above mean sea level 
The di from De Color dais h 10 mit 
The crossties on the railroads are spaced | mile apart. 
Rellef Shading by R. W. Berry 
Sheet No # 
M. R. CAMPBELL, Geologist A. C. ROBERTS, Topographer 
1922 
. 
EXPLANATION 
Age i 
in feet 
8 Gravel in river bottoms and terraces Quaternary i 
F ee oe a ae Our. rane age a Tertiary (Eocene) 3,400 
H Sandstone, shale, and coal beds (Mesaverde formation) 2,825 
J Dark marine shale (Mancos shale) : Upper Cretaceous 4,000 
M_ Brown sandstone (Dakota sandstone) 50 
N vex 2 es i pcan’ Cie ce Sct gee eo) Cee T 
f tion) and Jurassic 480 
P _Brick-red massive sandstone Triassic 300 
X Granite Pre-Cambrian 
Lava flows (basalt, andesite, latite, rhyolite, and 
7 tuff-breccia) = 
