150 University of Kansas Geological Survey. 
formation of Cragin. The thickness of this sub-formation increases 
quite rapidly in passing from the southern part of Comanche county 
to its western border. In this bluff are loose pieces of pinkish, shaly, 
limestone containing Ostrea; and also sandy, yellowish, shales of 
the upper Kiowa. The top of this bluff is 95 feet above the level 
of Sand creek (or Kiowa creek) to the west. Judging from the 
hills one half mile east of this place, the Red-Beds extend some- 
what higher and the loose Kiowa shales are below the horizon of 
the Comanclie. On the western side of Sand creek are exposures, of 
some thickness, of the black shale belonging to the Kiowa. This 
iocality may be regarded as forming the eastern end of the Clark 
county area of the Comanche series. On the fianks of the hills to 
the northwest of Sand creek, on section 21, Irwin township, 11¢ 
feet above creek level are thin black shales exactly similar to those 
of the lower Kiowa in the southeastern part of Kiowa county. 
Some of this shale weathers to a bluish and gray tint and a little 
of it to a brownish yellow. Near the base of the shale as exposed 
in a small draw is a 2 or 3 foot layer of soft yellowish sandstone 
containing fossils, as Cyprimeria and other species. At this place 
the top of the Red-Beds is not shown, the lower slope of the hill 
being covered by soil; neither is the line of contact between the 
Isiowa and Tertiary shown, this portion also being similary covered. 
Between 25 and 30 feet, however, of the yellowish and black shales 
were measured at this point. On the county map of Comanche 
county an elliptical area in the western part of Irwin township is 
marked “Coal Cropping.” After an examination of this township 
it is evident enough that the Kiowa black shales suggested the 
idea of coal beds to the early settlers. In a similar manner coal 
was also inferred to occur in Powell township on the headwaters 
of Big Mule creek in the northeastern part of the county. In the 
eastern part of the latter area, black shales of the Kiowa outcrop 
in the creeks and draws. From the western part of Irwin town- 
ship the Kiowa shales were followed westerly along the hills some 
distance to the north of Bluff creek, and were found to have a con- 
stuntly increasing thickness. The top of the Red-Beds on section 21 
of Irwin township is at least 40 feet higher than at their occurrence 
on the branch of Cavalry creek five miles southwest of Coldwater. 
