CARBONIFEROUS FORMATIONS OF THE OZARK UPLIFT 



RESUME. 



343 



On the north slope of the Ozark uphft the Burhngton (in places 

 the Chouteau) limestone rests unconformably upon the Cambro- 

 Silurian formations, and the Pennsylvanian formations, in turn, 

 rest unconformably upon the Burlington limestone and the Cambro- 

 Silurian rocks. During the late Mississippian period, solution was 

 unusually active, and the Saline Creek cave-conglomerate and 

 Coal-Measure shale lie largely in solution cavities, developed pre- 

 vious to their deposition. The Graydon sandstone, when it rests 

 on Cambro-Silurian rock, occupies normal erosion valleys. The 

 present position and extent of the Carboniferous deposits is deter- 

 mined by several factors, among which the pre- Carboniferous and 

 inter-Carboniferous land surfaces and post-Carboniferous erosion 

 are important. 



Sydney H. Ball. 



Geological Department, 

 University of Wisconsin. 



