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nourishment projects on Presque Isle Peninsula. A total of 416 kilometers of 

 seismic profiles and 49 cores with an average length of 4.1 meters were 

 analyzed along with 23 grab samples. 



Analyses of the seismic profiles, sediment cores, and grab samples show 

 that four major geologic units are present. Paleozoic shale bedrock with a 

 lakeward slope underlies the entire region. Shale crops out at the lake floor 

 shoreward of the -10-meter contour and attains depths of -87 meters about 18 

 kilometers offshore. Thick units of glacial sediment overlie the bedrock sur- 

 face and include assorted tills, stratified glaciof luvial sand and gravel, and 

 stiff lacustrine muds. Beach and dune sands are present on the top of the 

 transverse ridge between Long Point, Ontario, and Presque Isle. These sands 

 result from the reworking of the morainal sediments comprising the ridge by 

 coastal processes of an earlier Lake Erie. Modern soft muds are accumulating 

 in deepwater, low-energy areas adjacent to the ridge and Presque Isle platform. 



Sand and gravel of suitable size distribution and composition are present 

 in large quantities in two locales. The ri-dge and platform features contain 

 about 39 million cubic meters of proven resources within 2.3 meters of the 

 lake floor; the seismic profiles of the subbottom show that two to three times 

 that volume may be present if the entire ridge is considered. A second 

 morainal ridge off Dans Beach, west of Erie, is judged to contain several 

 million cubic meters, but its closeness to shore and the distance of 25 kilo- 

 meters from Erie limit the fill potential of the ridge. 



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