DETAILED RECORDS. 247 
OHIO. 
12~>G. Well near Rockbridge, Hocking County. 
Fell begun March 30, 1905; completed May 17, 1905. Authority, R. H. Derry and John Huddleston, 
drillers. Samples preserved. Geologic correlations by S. Sanford.] 
| This well gives an interesting section in the Sugar Grove pool, the most important 
jatural-gas reservoir in Ohio outside of the Trenton pools. The rocks penetrated range 
l age from Carboniferous to Silurian. The formations are Pottsville (Pennsylvanian), 
Logan group, Cuyahoga and Sunbury shale and Berea sandstone (Mississippiau), Bedford 
nd Ohio shales and Onondaga limestone (Devonian), Helderberg and Niagara limestones, 
pnton limestone and shale (Silurian). 
lecord of well No. 7 on Charles Wharton farm, Good Hope Township, 3 miles southwest of 
Rockbridge. 
Feet. 
oft red or orange sand 0- 1 
.oft orange and yellow sand and clay, a rotten clayey sandstone; landed 
8-inch drive pipe at 43 feet 1- - 43 
ottsville ( ?) and Logan : 
Soft buff sandstone 43- 85 
No record or sample - 85- 125 
Soft red, buff, and light-buff sandstone . . 12.5- 190 
Soft white and light-gray sandstone; fresh soft water was struck at 175 
feet; at 340 feet the water rises to within 150 feet of surface 190- 340 
Soft brownish sandstone. 340- 380 
Soft light-gray gritty sandstone 380- 420 
Harder gray limy sandstone, very gritty 420- 440 
Jo record or sample 440- 450 
Cuyahoga and Sunbury: 
Soft gray shale 450- 530 
Soft gray limy sandstone 530- 550 
Soft dark-gray shale 550- 620 
Soft black shale 620- 640 
A/ery soft dark-gray shale 640- 660 
Serea: 
Hard light-gray limy sandstone; show of oil and a little gas 660- 665 
Hard dove-colored sandstone — salt water; sandstone is about 33 feet 
thick 665- 685 
3edford : 
Soft gray gritty shale 685- 700 
Soft red shale. 700- 780 
)hio: 
Soft black, dark-gray, and black shale 780- 875 
Soft gray shale 87.5-1, 000 
Soft black or dark-gray shale 1, 000-1, 165 
Soft dark-brown, slightly limy shale 1, 165-1, 205 
Harder and darker, more or less limy shale. 1, 205-1, 265 
Hard gray limy shale 1, 265-1, 285 
Hard dark-brown shale 1, 285-1, 305 
Hard and soft dark brownish-gray limy shale 1, 30.5-1, 365 
Soft light-gray limy shale 1, 365-1, 370 
Soft dark-gray, almost black shaly limestone. 1, 370-1, 390 
Soft light-gray limy shale 1, 390-1, 504 
