88 ENVIRONMENT OF VERTEBRATE LIFE, ETC. 



"Wellington shales. — This formation consists largely of bluish-gray to slate- 

 colored shales, but contains some red ones, and in the southern part of the State 

 beds of impure limestone and calcareous shales, together with occasional beds of 

 gypsum and dolomite. Limited sahne deposits are reported, but no rock salt." 



This series has been shown by Beede and Sellards' to be singularly 

 persistent through the State. They say : 



"From what has preceded it will be seen that the strata of the lower Permian 

 are remarkably persistent and uniform when the great extent of the outcrop is 

 considered. The Cottonwood limestone, though only about 6 feet thick, persists 

 with every detail of structure and fauna over lOO miles of strike and several times 

 as great an outcrop, though it has not been identified with certainty in the 

 southern part of the State. The Garrison formation extends entirely across the 

 State, with but slight modifications in the southern part, such as the thickening 

 of some of its limestones and the possible interpolation of others. The Wreford 

 limestone is remarkably uniform throughout the entire distance from Nebraska 

 to the southern line of Kansas, being most highly developed in the central part 

 of its outcrop in the region of Cottonwood Falls. In the Matfield shales about 

 the only change worthy of special notice is the thickening of a layer of limestone 

 and the coming in of an additional one in the southern part of its outcrop. There 

 are no striking changes in the Florence flint, aside from a slight fluctuation in its 

 thickness, being somewhat thicker in the central and southern regions." 



Toward the southern line of Kansas the limestones shade into sand- 

 stones and shales. This significant change is described by several authors. 



"In tracing the outcrop- of the limestone formations of the Carboniferous of 

 Kansas, the writer observed that in going southward there is a gradual transition 

 in the character of the sediments to those which are more arenaceous, and that 

 there is a thickening of the shales and sandstones and a thinning and final dis- 

 appearance of the limestones. * * * 



"* * * From what is known of the Permian limestones of Kansas, they will 

 be found, when followed southward, to diminish in thickness, and this change 

 will be accompanied by a transition to more sandy beds. * * *" 



The "Wellington Shales" are probably represented southwestward by 

 formations which are red. The approximate limit of the red color is a line 

 diagonal to the strike of the formations, and is found to correspond in a 

 general way with a line drawn by Mr. Cummins as separating the Carbon- 

 iferous and Permian. 



"The distinctions which have been thus far outlined in Kansas do not hold 

 where the rocks are followed southwestward along their strike into Indian Terri- 

 tory. Approximately along the Arkansas River, or a little south of that stream, 

 the interstratified limestones disappear from that section, and the formations are 

 accordingly shales and sandstones. Moreover, the rocks in Indian Territory 

 gradually assume a red color in the higher portions of the section, the line of 

 transition to this color being diagonal to the strike." 



' Beede, J. W., and E. H. Sellards, Stratigraphy of the Eastern Outcrop of the Kansas 



Permian, Amer. Geol., p. 109, 1905. 

 2 Adams, G. I., Carboniferous and Permian Age of the Red Beds, Amer. Jour. Sci., vol. xu, 



P- 383. 1901. A full description of conditions, with maps, is given by Adams in the 



Bulletin of the Geological Society of America, vol. 14, p. 191, and in Bull. 211, U. S. 



Geological Survey, 1903. 



