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(September to April). Peak recession occurred before ice buildup (between 

 November and December) and just after ice breakup (in the spring, March to 

 April). Lake ice was found to be an effective shore protection agent during 

 the stormiest months of January, February, and March. Till and mixed till 

 bluffs tended to erode less than bluffs composed of sand, but no clear 

 dependence on bluff composition was found. 



An analysis of the content and median sand size of 519 sediment samples 

 collected from both the foreshore and the backshore during the final 15 months 

 of surveying shows that backshore sediments are generally finer and more 

 uniform than foreshore sediments. High and low concentrations of gravel, 

 usually found on the foreshore, were characteristic of specific profile 

 lines. Deposits of heavy minerals, predominantly magnetite, were usually 

 found on the backshore. 



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