210 R. T. Hill—Outlying Areas of the Comanche 
Wie 
Ila, Belvidere Shale. ds 
52{Black: or blue shale- |. ...22¢. 22 eee eee 26 
6.. Oyster bed; sandy matrix $2 2200 tea eee 2 
1. Black shale 2.2. i... 20 720 ee eee aS ip 
8.: Oyster bed, in shale... 32 - Fee = See 8 
9, Black shale..:....-...22.2 20222 223 =n 
10, Oyster bed, in shale..--. 2252252250. | 3 
11. Blacksshale.... 2.1.02 See 3 
12, Oyster bed, in shale .._/_- 2) 2232 2a 8 
13, Lower part, black shale with much gypsum 
Upper part quite ferruginous .--_...... . 4 
14, Oyster bed with much gypsum ....----._-27e2 8 
15. Black shale .. 020-2. 22202 2. 2 
16. Oyster bed weathered: -40J2b. 32222 22a 1 
17. Black shale weathered ___=__-2_ = 2-3 3 
18. Oyster bed, cap on top of cit. 22 = 2235 ae eee 2 
19. From top of cut to top of next Gryphza bed_. 20 
20. To top of next Grypheabed)_2 224-22 eee 12 
21. To top of next Grypheeavbed 2-4 2 nee eee 4 
22, To top of next Gryphea bed... -....--.__.- 12 
Total, _... ae 102 
III. The ‘‘ Dakota” Sandstone. 
23. A small nipple of nearly black ferruginous sand- 
stone, consisting of coarse odlitic-like grains, 
and containing stems of plants. This is the 
character of sandstone generally called Dakota 
in Katisas _. 0.2222 ee ee 20 
IV. Plains Tertiary : 
24. White mortar-like rock with calcareous matrix 
enclosing fine grains of sand..-.-.-.-.----- 11 
Thirty rods north of the line of the section the Tertiary 
(No. 24) rests directly on the Belvidere shales, the Dakota 
(No. 23) having been eroded. 
These two sections, taken some miles apart, are sufficient to 
show the general character of the structure and sedimentation 
of the beds. They practically agree in thickness and character 
with the sections of the Belvidere region previously given by 
Prof. Cragin.* | 
Reviewing both these sections above the Red Beds (No. 1) 
and below the Dakota (JII), they consist of continuous deposits 
of shallow marine sedimentation, showing (Ia) a group of the 
sand beds at the base (the Cheyenne sandstones of Cragin) - 
grading into an upper portion of thin blue and black shales ee 
These shales resemble lithologically the similar blue and blac 
shales of the Meek and Hayden section as seen in the plains and 
Rocky Mountains of the northwest, and not those of the beds 
* Bulletin Washburn Laboratory, vol. ii, No. 11, pp. 75-76, 1890. 
