PENNSYLVANIAN. 465 



stone, Calhoun shales, Topeka limestone, Severy shales, Howard limestone, Scranton shales, 

 Burhngame limestone, Willard shales, Emporia limestone. Admire shales, Americus limestone, 

 Elmdale formation, Neva limestone, Eskridge shales, Cottonwood limestone, Florena shales, 

 Neosho formation. 



These formations are exposed along the Flint HUls in southern Kansas, but near the Okla- 

 homa line most of the limestone members thin out and disappear, while sandstones come in 

 and thicken to the south. No accurate section across the group has been made in Oklahoma, 

 but it is probable that the group does not thicken to the south as rapidly as do the groups 

 heretofore described. In fact, there is some evidence which indicates that in Lincoln, Potta- 

 watomie, and Cleveland counties the rocks representing the southern extension of the Ralston 

 group are not so thick as they are farther north. 



In southern Pawnee and northern Payne counties the color of the rocks in the Ralston 

 group changes and becomes a deep brick-red and so continues to the southern limits. This 

 area includes the greater part of the so-called Chandler beds mentioned above. 



HIGHER KOCES. 



Above the Ralston group the sequence of limestones and shales with occasional sandstones 

 continues uninterruptedly for several hundred feet. The Kansas geologists have described 

 these rocks under the following names, the oldest below: 



Wellington shales. 

 Marion formation. 

 Winfield limestone. 

 Doyle shales. 

 Fort Riley limestone. 

 Florence flint. 

 Matfield shales. 

 Wreford limestone. 



The limestones contain much flint, which, being resistant, withstands erosion, giving 

 rise to a series of pronounced escarpments, which, in southern Kansas, constitute the Flint 

 HiUs. The rocks of the Marion are less resistant and form few pronounced escarpments. The 

 Wellington shales are all soft rocks and weather into a flat plain. 



In Oklahoma, all these formations pass into the Red beds along the line indicated on the 

 map. Several of the limestones, particularly the Wreford, the Florence, and the Fort Riley, 

 extend several miles into the Red beds before finally losing their color and merging with red 

 sandstones and shales. 



This peculiarity of relations is represented on the map in Kay and adjoining counties, 

 where there is exposed an area of non-red Permian rocks, triangular in shape, bounded by 

 the Kansas line, the Wreford limestone, and the eastern margin of the Red beds. 



The Pennsylvanian terranes of Iowa are described as the Missouri and Des 

 Moines groups. Smith ^^^ has the following note on the Missouri: 



The Missouri of southwestern Iowa is composed of shales, limestones, and limited amounts 

 of sandstone. The shales, which comprise much the greater part of the strata, are generally 

 calcareous — so much so that even those in immediate contact with the coals effervesce readily 

 with acid. The limestones occur in layers from an inch or two in thickness to ledges 20 feet 

 thick. Usually the limestones are highly fossiliferous. In all the Coal Measures exposures 

 of Adams, Montgomery, Page, and Taylor counties not a single sandstone is to be found. Deep 

 drillings also show a total absence of sandstone in the Missouri in these counties. 



The Des Moines is described by Lees ®^^ as follows : 



The beds of the Des Moines stage are usually divided in a broad way into three general 

 divisions. These, as indicated in the section, are, from above downward, the Pleasanton, the 

 Appanoose, with its equivalent beds farther northwest, and the Cherokee. Of these three the 

 lower division, the Cherokee, is the most important, in Iowa as well as in Missouri and Kansas. 

 "' * * It will be seen from the section that shales are the preponderating element in this 

 48011°— 12 30 



