C. N". Gould — Series of Transition Beds, etc. 169 



Art. XXIII. — On a Series of Transition Beds from the 

 Comanche to the Dakota Cretaceous in Southwest Kansas ; 

 by Charles Newton Gould. 



During the last decade the geology of Southwest Kansas 

 has received considerable attention. Such earnest investi- 

 gators as St. John, Hay, Cragin, Williston, Hill, Haworth, 

 Frosser, Vaughan and Ward, by their published articles have 

 made this region familiar to American geologists. Probably 

 the most exhaustive report is that of Professor Prosser." To 

 his excellent review of the literature the reader is referred. f 



The Cretaceous of the region is conformable throughout and 

 everywhere rests unconformably on the eroded surface of the 

 subjacent Triassic (?) Red Beds and is covered by the Tertiary 

 or by the Pleistocene. It begins near Sun City in north- 

 western Barber county, and gradually thickens westerly, 

 attaining its maximum on the upper Medicine river west of 

 Belvidere. It thins out to a mere line at Coldwater, again 

 thickens on Bluff, Bear and Sand creeks in Clark county and 

 finally disappears at the Big Basin in the western part of the- 

 county. As stated by Professor Prosser,J the lower part of 

 the Cretaceous — consisting of two formations, the Cheyenne 

 sandstone and the Kiowa shales,§ — undoubtedly belongs to the 

 Comanche Series. 



The Cheyenne sandstone is composed mainly of coarse- 

 grained, friable, false-bedded sandstone. Its color is normally 

 yellowish or gray with streaks and blotches of red, pink, brown 

 or black. The lower part contains many smooth, water-worn 

 pebbles and occasional lenticular masses of bluish clay, while 

 the upper part consists of alternating layers of sandy shale and 

 more or less argillaceous sandstone, containing much lignite 

 and a most interesting flora, consisting of ferns, conifers, dico- 

 tyledons, etc. No animal fossils have been found. The maxi- 

 mum thickness is probably between 50 and (30 feet. 



The Kiowa shales, which lie on the Cheyenne, consist of 

 bluish-black to yellowish papyraceous shales with numerous 

 layers of limestone, containing great numbers of marine 

 invertebrates. In the lower part of the shales are found ver- 

 tebrates and insect remains. The maximum thickness reported 

 by Prosser is 14-0 feet. 



The presence of Dakota-like sandstone in both the Belvi- 



* University Geological Survey of Kansas, vol. ii, 1896, pp 55-194. 



f Ibid., pp.' 96-1 11. % Ibid., p 111. 



§ These names were first used by Professor Cragin. See Bulletin Washburn. 

 College Laboratory of Natural History, vol. ii, December, 1889, p. 65, and Colo- 

 rado College Studies, vol. v, April, 1893, p. 49. 



