The typical broad, gravel-dominated beach prevailed until late fall of 

 1971 when a 10-foot loss to the dune bluff and loss of all of the beach 

 occurred. As before, the beach recovered by the next survey period. A 

 prominent gravel ridge formed shortly after breakup of the shore ice in the 

 spring of 1972. The ridge prevailed for at least 2 months, serving as some 

 protection to the backshore zone. Heavy mineral concentrations during late 

 June indicated that there was erosion to the beach followed by rapid recov- 

 ery. 



Little change to the beach was noted during the summer and fall of 1972, 

 with the exception of some erosion in September and December. There was 

 recovery in the intervening period. The most significant period was in the 

 spring of 1973 when 11 feet of the terrace eroded. There was nearly com- 

 plete erosion of the beach during June 1973. 



b. Profile Site 2 . A steep sand bluff extends over 250 feet above the 

 lake immediately behind the active beach. Much of the slope is covered 

 with vegetation which acts to stabilize the slope even though it is at or 

 in excess of the angle of repose. 



At the initiation of the study (August 1970) , there was a rather broad 

 beach of sorted sand. During September 1970, much erosion of the beach 

 occurred which caused the usual concentration of heavy minerals in the 

 backshore area. Although the beach recovered well during the following 

 fall, the heavy mineral sand remained. More beach erosion and heavy min- 

 eral concentration occurred during July 1971. 



There was no significant change to the beach through the fall of the 

 second year although a slight narrowing was evident in December 1971. The 

 heavy mineral concentrate which prevailed at this site for the previous 18 

 months was covered with a veneer of sand during the spring of 1972. Maxi- 

 mum beach width was reached during the June 1972 survey, followed by beach 

 erosion during July. 



Nearly the entire beach eroded during September 1972, causing the first 

 erosion to the bluff behind the beach. There was a pronounced accretion of 

 the beach during October and some bluff retreat in November 1972. Follow- 

 ing the ice breakup in the spring of 1973, erosion again was severe with 

 more bluff retreat. Recovery occurred in June, followed by more beach 

 erosion during July 1973. 



c. Profile Site 3 . This site is adjacent to Bar Lake in Manistee 

 County. The beach is bounded by a terrace of beach and dune sands that 

 rises 10 to 20 feet above the lake. Sediment is mostly sand with scattered 

 fine gravel occasionally present in the plunge zone only. 



At the initiation of the study there was a broad beach; however, ero- 

 sion occurred during September 1970. Most of the beach recovered before 

 the next survey. This was followed by minor beach erosion during December 

 and terrace erosion in January. Erosion to the beach occurred after ice 

 breakup the following early spring. Although recovery provided a well- 



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