352 



abstracts: geology 



GEOLOGY. — The Devonian and Mississippian formations of north- 

 eastern Ohio. Charles S. Prosser. Bulletin 15, Fourth Series, 

 Geological Survey of Ohio. 1912. 

 This bulletin contains a description of the Devonian and Mississippian 

 formations as followed from Rocky River Valley west of Cleveland east- 

 ward across northern Ohio into the western part of Pennsylvania. A 

 large number of sections are described and some of the most striking 

 outcrops or formation contacts are illustrated by half-tones. 

 The formations of the area described are classified as follows: 



SYSTEM 



Carboniferous 



SERIES 



Pennsylvania!! . 



Mississippian 



Devonian 



FORMATION 



MEMBER 



Pottsville formation 



Royalton formation 



Sharon conglomer- 

 ate 



Sharpsville s an d - 



stone 



Orangeville forma- [Brecksville shale 



-j Aurora sandstone 

 [ Sunbury shale 



Bedford formation 



I Sagamore sand- 

 stone 

 Euclid sandstone 



Cleveland shale 

 Chagrin formation 



In the above table the Euclid and Sagamore members are merely two 

 sandstone lentils of the Bedford and they do not represent the thickness 

 of the entire formation. The Sunbury shale, Aurora sandstone and 

 Brecksville shale represent the entire thickness of the Orangeville for- 

 mation, while the Sharpsville sandstone and Sharon conglomerate repre- 

 sent only the lower part respectively of the Royalton and Pottsville 

 formations. The Orangeville formation of the Second Pennsylvania 

 Survey has been adopted for the Ohio classification with the same limits 

 that Dr. I. C. White gave it near the Ohio-Pennsylvania State line, viz., 

 from the top of the Berea grit to the base of the Sharpsville sandstone. 



The Cuyahoga terrane of Newberry in the Cuyahoga Valley, which 

 is its typical region, may readily be divided into two formations,- the 

 lower one about 125 feet thick consisting largely of blackish shales which 



