analyzer (RSA) . Of the sample, 5 to 7 grams were inserted in the 

 settling tube and a cumulative curve was produced on the recorder. After 

 a second part of the sample was run a comparison was made between the 

 curves. If both curves were similar, the first one was analyzed; if they 

 were different, another part of the sample was analyzed and the average 

 value of the three curves was used. Mean grain size, sorting, and skewness 

 were determined by the graphic method, using the 16-, 50-, and 84-percentile 

 values from the RSA curves. 



V. PROFILE DESCRIPTIONS 



The 26 sets of profile data have been computer-plotted and are presented 

 in the Appendix. The bluff or terrace erosion for the 17 profiles during 

 the study period is summarized in Table 4. Descriptions of the changes, 

 vertical and oblique photos, bench mark locations, and geomorphology of 

 the profiles follow. 



1. Profile Site 1 . 



Erosion of the low-lying dunes behind the beach (Fig. 6) was modest 

 during each of the 2 study years. The dunes were cut back 17 feet (7 feet 

 in 1970-71; 10 feet in 1971-72J, and all erosion occurred during the fall 

 storm period. 



Shortly after breakup of the shore ice in spring, a distinct subaerial 

 ridge and runnel feature, composed almost entirely of imbricated pebbles 

 and small cobbles, was present during both years. The ridge served as 

 excellent protection for the sand bluff during spring storms. The ridge 

 was not breached or destroyed for at least 2 months. 



2. Profile Site 2. 



This site (Fig. 7) was one of the few where no erosion of the sand 

 bluff occurred during the entire study period. There was some erosion of 

 the beach as evidenced by lag concentrates of heavy minerals. It is 

 possible only to speculate on the lack of erosion since it actually 

 appears to be one of the more likely sites for rapid erosion. The beach 

 is narrow and steep, and an unstable sand bluff extends over 250 feet 

 above the lake immediately behind the beach. The area beginning about 

 200 yards to the south of the site has also undergone severe bluff erosion 

 and the loss of a dwelling is imminent. The resident of the dwelling 

 has stated that this erosion is the worst in 40 years. Photos from the 

 1953-54 period of high water show a broad sand terrace and a wide beach 

 fronting the dwelling. 



3. Profile Site 3 . 



The sand terrace at this site (Fig. 8) experienced only 4 feet of 

 recession during 1970-71, and 5 feet the following year. All but 1 foot 

 of this occurred in late fall or early winter during two 4-week periods. 



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