24 THE BOOK CLIFFS COAL FIELD. 
OCCURRENCE AND TJilCKNESS. 
The following description begins at the east and proceeds westward. 
In connection with it the map (PL I), the stratigraphic section (PI. 
Ill), and the detailed coal measurements shown on Plate VIII will 
be of service. 
At the east end of the Book Cliffs two workable beds of coal are 
known. The lower one occurs between 35 and 60 feet above the 
top of the Mancos shale, and, though variable, is commonly about 
4 feet thick. The upper coal is thicker, in places measuring 9 feet, 
and occurs from 200 to 500 feet above the lower bed. These coal 
beds have been prospected at several localities between the Cameo 
mine (No 1 on the map, PL I) and the Farmers mine (No. 13), and, 
though they have not been actually traced throughout that distance 
and are known to vary in thickness, the beds appear to be continuous. 
Besides these two main coals there are usually other thin beds, but 
none of commercial importance has yet been found. 
The following detailed measurements made in the face of the cliffs 
a quarter of a mile west of the Book Cliff mine show the succession 
of the strata at that place and indicate the general stratigraphy of 
the coal measures, although no two sections are exactly alike: 
Section of coal-bearing rods one-four/]) mile /rest of Book Cliff' mine. 
Ft. in. 
Sandstone, massive buff 35 
Sandstone, buff 15 
Shale, drab and sandy 15 
Coal and bone .- 1 3 
Shale, drab 17 
Shale, carbonaceous 12 
Sandstone, buff 12 
Shale, drab 1 4 
Bone and coal 1 6 
Shale, drab 1 4 
Bone and coal 1 9 
Clay 2 
Bone and coal 1 9 
Shale, drab 2 
Sandstone, buff 7 
Shale, sandy 1 4 
Shale, carbonaceous 6 
Shale, drab 9 
Coal 1 6 
Shale, drab ■ 1 8 
Sandstone, buff * 2 
Shale, carbonaceous and bone 6 
Sandstone, buff 3 
Shale, carbonaceous 2 6 
Sandstone, massive buff 6 6 
Shale, carbonaceous 17 
