534 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



the moraine carries knolls about 10 feet in height and also ridges with 

 northeast-southwest trend rising 12 to 20 feet above the bordering plains. 

 On each member of the moraine, from the Olentangy eastward, swells 

 are but 5 to 10 feet high, and rather scattering, so that the belts are some- 

 what less distinct than in the remainder of their course. Indeed the 

 undulations are scarcely strong enough to merit the term morainic, though 

 the belt can be distinguished from the plane tracts each side. 



THICKNESS AND STKUCTURK OF DRIFT. 



The general thickness of the drift in this belt, aside from the buried 

 vallej^s, is 50 to 75 feet, but few borings showing greater depth than 75 

 feet to the rock. Where greater depth is found it is presumabl}^ at a 

 filled-up valley; but the drift surface is so smooth and deep borings are so 

 few that the courses and connections of preglacial A^alleys can not well be 

 traced. 



This moraine carries more gravel than the Powell moraine, yet it 

 consists largely of till. Beginning at the northwest, the principal well 

 sections obtained are described below. 



About 3 miles west of Roundhead a well at a schoolhouse struck rock 

 at 40 feet. Just north of the village of Roundhead James Dunlap has a 

 well 164 feet deep which did not strike rock. It was mainly through blue 

 till. Three miles north of Roundhead, on Mr. Street's farm, rock is struck 

 at less than 90 feet. One mile northwest of Roundhead, at Daniel Simpson's, 

 a well 140 feet deep struck no rock. There is said to be an outcrop of rock 

 in the Scioto Marsh, about 4 miles northwest of Roundhead, though several 

 flowing Avells on the marsh at about the same level struck rock at 80 to 90 

 feet. About 4 miles northeast of Roundhead, at a schoolhouse, I'ock was 

 struck at 80 feet. At Samuel CoUins's, near the south end of the Ta5dor 

 Creek esker, 2 wells 35 feet deep are mainly through blue till, and struck 

 no rock. 



At Belle Center much variation in the altitude of the rock surface is 

 found. There is a quai-ry in the northeast j^art of the village at a some- 

 what higher level than the railroad station. Two gas wells in the village 

 penetrate in one instance 44 feet, and in another 160 feet of drift. The 

 greater part of the drift in the gas wells is till. Several flowing wells at 

 Belle Center have a depth of 18 to 25 feet. They penetrate about 10 feet 



