XXXV. Topography and Geology of the 

 Chautauqua Region 



1. This region has two great physiographic divisions. These are 

 separated by what is known as the " Hill " or escarpment, which ex- 

 tends east and west, parallel to Lake Erie. The lakeward division is 

 known as the Erie forelands, while that portion to which the Erie 

 escarpment acts as a frontal bluff is known as the uplands. 



2. The surface features of the forelands are very regular. They 

 present a slightly undulating ascent from the present wave-cut bluff of 

 Lake Erie towards the escarpment, in which the gradient will vary from 

 100 to 200 feet to the mile. 



3. From the crest of the escarpment the Chautauqua uplands are of 

 a rolling character. The hills are elongated in form, their major axis 

 lying north and south, while they rise in successive tiers east and west, 

 varying in altitude from 100 to 500 feet above the upland valleys. 



4. The surface geology of this region is typical of a glaciated area. 

 In the uplands the physiographic features plainly show the action of the 

 great continental Ice Sheet that at some former time covered the region. 

 Erratic bowlders from a few inches to 3 or 4 feet in diameter are thickly 

 scattered over the northern slopes of the hills. The crests of the hills 

 are elongated in form, sloping in convex curves to the valley. 



5. Along the crest of the escarpment there is a belt of glacial debris 

 of sand, gravel, and bowlders known as a moraine, which varies in 

 width from two to three or four miles and extends in a line approxi- 

 mately parallel to the shore of Lake Erie. This belt probably marks 

 a point where the ice tarried in its recession. Numerous kames, terraces, 

 and kettle-holes occur throughout the valleys. 



6. The Erie forelands also present a very interesting feature of 

 glacial geology in the ancient beach lines. These rise in successive 

 terraces from the present lake level to the base of the escarpment. The 

 number varies from one to four or five, but usually there are two which 

 are quite distinct and well defined. The material is usually a typical 

 beach gravel, which in some places has been entirely carried away by 

 the forces of erosion, leaving only the shore topography to mark the 

 former location of the beach. 



7. Between these beach lines and the present shore of Lake Erie are 

 found finer sediments, which were laid down as offshore deposits at the 

 time the beaches were formed. In a number of instances the streams 

 have cut down through these sediments, exposing the underlying bowlder 

 clay that marks the former presence of the Ice Sheet. 



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