172 University of Kansas Geological Survey. 
mass of the Big Basin sandstone here 10 to 12 feet in thickness. 
This sandstone is also frequently streaked with red and shows a 
somewhat gradual passage from the physical conditions of the Red 
Beds to those prevailing in its own case. In places it is fase bedded. 
Plate X XTII. of the Big Basin sandstone in the Big Basin represents 
clearly the massive stratum and conspicuous outcrop of this sand- 
stone in the eastern wall of the Big Basin. The ledge shown in the 
upper part of the picture is the one from which large blocks of sand- 
stone have fallen. 
This is the typical locality for the Big Basin sandstone of Cragin 
who described it as a “Massive, blocky, red and grayish-white sand- 
stone.”! He regards it as forming the upper number of the Red- 
Beds or Cimarron series. As has been already stated it seems to 
the writer that this sandstone might more properly be correlated 
with the Comanche series and regarded as representing in Clark 
county the Cheyenne sandstone of Kiowa and Comanche counties. 
Professor Cragin has considered the transitional nature of the 
passage from the big Basin sandstone to the Comanche which he 
stated might be regarded as reinforcing “the earlier generally ac- 
cepted view that the ‘Red-Beds’ were Jura-Trias, or at least partly 
so; but the bond of continuity which has already been referred to as 
apparently existing between the Cimarron series of Kansas and the 
paleontologically proven Permian of northern Texas outweighs any 
argument of that sort, and indicates rather that the upper and here 
hghter-colored zone of the Big Basin sandstone was softened by the 
invading waters of the Belviderean sea, and its sediments partially 
and then wholly rearranged as the (for this point) initial deposits. 
of the latter, only gradually becoming supplanted by sediments con- 
veyed from other sources.’” 
Of course if the Big Basin sandstone be regarded as the strati- 
eraphic equivaient of the Cheyenne, then its continuity with the 
IkXiowa shales of the Comanche is exactly what would be expected. 
This explanation seems more satisfactory, especially when the great 
similarity of the lithologic characters of the Great Basin sandstone. 
1 FE. W. Cragin, Colorado College Studies, Vol. VI, p. 46. 
2 EF. W. Cragin, Colorado College Studies, Vol. VI, p. 648, Colorado Springs, Col. 
