ho 
ww) 
a 
LOGAN. | The Upper Cretaceous. 
Devil’s Canon Section: 
ad, Shale, 100 feet, Baculites ovatus, (bottom). 
2d, Mortar beds, 10 feet. 
ist, Plains marl, 8 feet (top). 
Hackberry Section: 
3d, Plains marl, 20 feet (top). 
2d, Sand, 3 feet. 
ist, Shale, 30 feet, Lucina occidentalis, (bottom). 
DAKOTA SHCTION FROM BROOKVILE TO LITTLE TIMBER CREHK, 
Plate XXXI, Figure 2. 
Resting on the Permian limestone at Brookville is a stratum of 
light blue colored shale. The shales appear in consecutive out- 
crops along the creek to Carneiro and westward. They are suc- 
eeeded above not unfrequently by beds of red or yellow shale of 
much the same texture. The shales are entirely argillaceous, but 
above are of arenaceous shales intercalated with thin layers of sand- 
rock. “The hills northwest of Brookville are crowned with layers of 
sandstone. The following outcrops serve to show the stratigraphy: 
First outcrop: 
6th, Sandstone, 10 feet. 
oth, Shales, 6 feet, yellow. 
4th, Sandstone, 6 inches. 
ad, Shales, ight yellow, 4 feet. 
2d, Sandstone, 4 inches. 
Ist, Blue shale, 30 feet (bottom). 
Second outcrop: 
6th, Sandstone, 6 feet (top). 
5th, Shale, 3 feet, yellow. 
4th, Sandstone, 3 inches. 
3d, Shale, 4 feet, yellow to red. 
2d, Sandstone, 5 inches. 
Ist, Shale, blue, 20 feet (bottom). 
