DEVONIC AND CARBONIC FORMATIONS OF SOUTH- 

 WESTERN NEW YORK 



With stratigraphic map of the Olean quadrangle 

 BY L. C. GLENN 

 INTRODUCTION 



Basis of paper. During the summer of 1900 the detailed geolo- 

 gic mapping of the Olean and Salamanca quadrangles in south- 

 west erji New York [see pi. 1] was undertaken by the United 

 States Geological Survey in cooperation with the New York State 

 Paleontologist, and the writer was placed in charge of the work. 

 The work was continued and finished the next summer. Mr Myron 

 L. Fuller assisted largely in the work on the Salamanca quad- 

 rangle during the latter season, and in both seasons Mr 1 Charles 

 Butts made extensive paleontologic collections from the two 

 quadrangles and the adjacent region. Reconnaissance work 

 was pushed southward to Bingham Pa. and westward across 

 McKean and Warren counties to near Corry Pa. 



Age of rocks and problems involved. The paleozoic rocks ex- 

 posed in the quadrangle extend from about the middle of the 

 Chemung up into the Carbonic. They consequently include the 

 Catskill or its equivalent and the boundary or transition be- 

 tween the Devonic and the Carbonic. Eastward in both New 

 York and Pennsylvania the distribution of the Chemung, the 

 Catskill and the Carbonic rocks and their relationship to each 

 other have received much study. Southward in Pennsylvania 

 the Carbonic rocks have been studied and the lower Carbonic 

 traced northward toward this region. To the west in Ohio the 

 Carbonic and Waverly have been studied and traced eastward 

 for some distance into northwestern Pennsylvania. The Olean- 

 Salamanca region, however, has been an unknown meeting 

 ground into which, when attempts were made to trace beds that 

 were distinct to the east, the south or the west, the tracings 

 became indistinct and the correlations uncertain. 



Purpose of paper. It is the main purpose of this paper to de- 

 scribe briefly the stratigraphic succession found in the Olean- 

 Salamanca region, to state the paleontologic conclusions so far 

 reached as to the age of the formations, and the results of the 

 efforts made to trace these formations into better known re- 



