414 INDEX TO THE STRATIGRAPHY OF NORTH AMERICA. 



J-K 17. OHIO AND EASTERN KENTUCKY. 



The Mississippian series on the east side of the Cincinnati arch consists chiefly 

 of argillaceous and sandy deposits which are in contrast to the limestones of the 

 west (Indiana) side. They have been described under the name Waverly since 1838 

 (Briggs) and 1869 (Newberry), but with various classifications. Above these 

 strata occurs a thin limestone which also belongs to the Mississippian and upon which 

 the Pottsville (Pennsylvanian) was laid down unconformably. Prosser ^*^'^^® has 

 recently reviewed the literature and sequence- of formations and his arrangement 

 has been in general followed by Chamberlin and Salisbury "** in the following table, 

 but Prosser called the Logan exclusive of the Blackhand a formation, and not a 

 group, the old "Logan group" including both the Logan formation and the 



Blackhand. 



Generalized section for Ohio."' 



a Prosser, Jour. Geology, vol. 11, 1903, pp. 520, 521. Geol. Survey Ohio, vols. 6, 7; Bull. No. 7, 4th ser., 1905. 



The correlation of this section with that of the typical Mississippian section 

 and the Appalachian equivalents on the east is discussed by Girty as follows i'®'^ 



In 1900 an effort was made to trace eastward into Pennsylvania the members of New- 

 Iberry's Waverly section in northern Ohio. The Berea grit of the Waverly group was found 

 to be the equivalent of the Cussewago sandstone of northwestern Pennsylvania. The Orange- 

 ville shale of that region is the basal third of the Cuyahoga shale, in part equivalent to Orton's 

 Berea shale. The Sharpsville sandstone, representing the middle portion of the Cuyahoga, is 

 probably the stratum producing the lower fajls at the village of Cuyahoga Falls. The MeadviUe 

 shale can with little doubt be correlated with the upper portion of the Cuyahoga, and it seems 

 probable that the Shenango sandstone and shale are the equivalents of the Logan group. 

 It is doubtful if the Corry sandstone is represented in Ohio, while the Bedford and Cleveland 

 shales probably die out before reaching the Pennsylvania line. 



The relations of the Waverly to the clastic formations of Pennsylvania and 

 West Virginia have been traced by Stevenson,^^*^ who uses the term Logan in the 

 sense given to it by Orton, rather than as restricted by Andrews and Prosser. 

 "Logan" in the following quotation thus comprises the original Logan formation 

 and the Blackhand formation. 



