42 STRUCTURE. 



its length between Copley and the Little Kanawha River, the 

 axis forms the bottom of a great structural canoe-shaped de- 

 pression, of almost perfect symmetry from every angle. In 

 the northeastern end of this basin is located the greatest oil 

 well ever drilled in West Virginia, the Copley Heirs No. 1 

 (363), which gushed oil at a rate of 10,000 to 12,000 barrels 

 daily. From the Kanawha River, the Pittsburgh Coal rises 

 continuously for 12 miles, until, at Crooked Fork, it has an 

 elevation of 900 feet, the rate of rise being 26 feet per mile. 

 Between Crooked Fork and Road Run, there is a high struc- 

 tural saddle where the coal horizon remains at 900 feet, for 

 more than two miles. 



Rosedale Basin. At the extreme western end of the 

 Grassland Syncline, where it ends against the slope of the 

 Chestnut Ridge Anticline, the Pittsburgh Coal horizon dips to 

 a low structural basin that is the most noticeable feature on the 

 structure map. The basin is almost symmetrical in form, four 

 miles long and two and one-half miles wide across the axis of 

 the syncline. At the outer rim, the coal has an elevation of 900 

 feet, but at the bottom, beneath Tanner Fork, it is only 725 

 feet, making a total dip of 175 feet. For convenience this 

 structural feature will be called the Rosedale Basin. It seems 

 evident that the basin was formed by a structural eddy devel- 

 oped at the intersection of two dynamic forces, one acting 

 upward to form the Chestnut Ridge Anticline, while the other 

 was acting downward to form the Grassland Syncline. 



Roanoke Syncline. The Roanoke Syncline, not previously 

 named or described, is a structural trough in southern Lewis 

 that branches from the Grassland Syncline three-fourths mile 

 northward from Brownsville, and extends southwestward, 11 

 miles, to the Braxton Line, beyond which it has not been 

 traced. Its course from Brownsville is almost south for five 

 miles, following closely the valley of the West Fork Rrver to 

 a point one-half mile northwest of Roanoke, where it veers 

 toward the southwest, crossing the Baltimore and Ohio Rail- 

 road at Peterson, and the Coal and Coke at the mouth of 

 Meadow Run, formerly known as Blake post-office. This syn- 

 cline is almost symmetrical about its axis, the rise of the rocks 

 being slightly faster on the east than on the western side. 



