ARTICLE II. 



NOTES ON THE GEOLOGY OF WEST VIRGINIA. 



BY JOHN J. STEVENSON, 

 Professor of Geology in the University of the City of New TorJc. 

 Read before the American Philosophical Society, Feb. i6, 1872. 



In this paper I propose to describe tlie carboniferous series as displayed in a portion 

 of Monongalia and Marion counties, West Virginia, the extension of that part of 

 Pennsylvania described in the reports as the Third Great Basin south of the Ohio, 

 first subdivision. 



Laurel Hill, the eastern boundary, appears to attain its greatest importance in the 

 neighborhood of Uniontown, Pa., from which point it gradually diminishes southward, 

 until at the Yalley Falls of the Monongahela River, about thirty miles south from the 

 State line, it becomes so insignificant that the Mahoning sandstone passes over it, 

 unbroken. The western boundary is the first sub-axis of the third great basin of 

 Pennsylvania, and was termed Brush Ridge in the report. It is almost parallel Avith 

 Laurel Hill in Pennsylvania, but near the line it turns towards the southwest, and 

 very soon ceases to affect the dip. The breadth of the sub-basin in its northern part 

 varies little from eight miles. I have chosen to regard this as the average width of 

 the section to be examined, although the western boundary soon disappeai's and the 

 sub-basin as such no longer exists. 



Through the whole district the Monongahela river runs with a course irregularly 

 north and south, cutting through Laurel Hill near Valley Falls. Its numerous tribu- 

 taries from the east afford excellent natural sections of the lov/er groups, while those 

 from the west afibrd equally satisfactory illustrations of the upper coals. Cheat River 

 I'uns through the northeastern corner. The village of Morgantown is on the bank of 

 the Monongahela, about six miles south from the State line ; and Fairmount, on the 

 same river, is twenty miles south from Morgantown. I shall make no refei'ence to the 

 portion lying north from Cheat river, as that has been fully discussed by Prof. W. B. 

 Rogers, in his report on property connected with the Prideva.le Iron Works. 



