644 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



more than 200 feet of drift, and iii one case reached a depth of 222 feet 

 without entering rock. There are places in the basin where rock is near 

 the surface, the deep part of the valley being much narrower than the 

 basin. 



No well records showing a large amount of drift were obtained along 

 the line of this moraine in northwestern Pennsylvania. Ordinarily water is 

 found at shallow depths in the valleys, so that there has been little need 

 for deep boring in them, while on the uplands wells usually strike rock at 

 'moderate depth. The wells at Bemis Point, in the valley of Lake Chau- 

 tauqua, referred to above, and a few in Conewango Valley constitute the 

 only records of deep wells which have been collected along this moraine in 

 western New York. Of those in Conewango Valley one near Randolph 

 reached a depth of 280 feet, one near Rutledge 314 feet, and one near 

 Dayton 330 feet without entering' rock. They penetrated blue clay nearly 

 the whole depth. Deep wells in Cattai'augus Valley, north of the Cleveland 

 moraine, are discussed on a later page. 



The deepest well records obtained near Cassadaga Valley are in Mill 

 Creek Valley at Sinclairville, about 2 miles from the junction with Cas- 

 sadaga Creek. Two wells on a drift bench standing 60 feet above the 

 creek reach depths of 105 and 125 feet without entering rock. They are 

 mainly through blue clay. 



The following table shows the thickness and to some extent the structure 

 of the drift in many other wells on or near the moraine. It includes wells 

 in the Grand River Basin that are at some distance north of the moraine. 

 Where the plus sign is affixed rock was not reached. The minus sign is 

 used where precise depth to rock is not known. Where owners' names are 

 not given there are usually several wells at about the same depth which 

 gave similar results. 



