. Changes in rates of shore retreat : Lake Michigan, 1967-76. Coast changes; Beach erosion. WITHDRAWAL f (Emergence). WATER LEVEL RISING ENCROACHMENT f (Submergence) 0. Verticol Chongcs b. Horizontal Chonges Figure 6. Terminology of vertical and horizontal shoreline changes. accustom the reader to viewing the data from the slightly different per- spective employed here. The most direct way to represent retreat of the shoreline would be to superimpose a set of shoreline maps. However, to depict on a page even a small part of the present study area, distances normal to shore would have to be exa
. Changes in rates of shore retreat : Lake Michigan, 1967-76. Coast changes; Beach erosion. WITHDRAWAL f (Emergence). WATER LEVEL RISING ENCROACHMENT f (Submergence) 0. Verticol Chongcs b. Horizontal Chonges Figure 6. Terminology of vertical and horizontal shoreline changes. accustom the reader to viewing the data from the slightly different per- spective employed here. The most direct way to represent retreat of the shoreline would be to superimpose a set of shoreline maps. However, to depict on a page even a small part of the present study area, distances normal to shore would have to be exaggerated; otherwise, even where the shoreline has retreated 35 meters, the change would not be evident. For example, note that in the aerial photo at the bottom of Figure 7, all shoreline positions for the last 10 years would overlie one another and be indistinguishable at this scale. Expanding the scale perpendicular to shore pulls the shore- lines apart as shown above the photo. Note the expansion also greatly distorts shoreline shape. Since the primary interest is in shoreline re- treat, not shape, all attempts to show shoreline shape could be abandoned and all shorelines referenced to their position on either the initial or- the final survey. Because the year of initial surveying differs among stations, shoreline positions are referenced at the top of Figure 7 to their final positions (as determined in October 1976). Figure 7 shows a two-step transformation of shoreline data (from map view), first to exaggerated distance from base line, then to exaggerated distances from the 1976 shoreline. Because the shoreline protrudes about 10 kilometers lakeward in the vicinity of Little Sable Point (Fig. 4), it is infeasible to depict both shoreline shape and changes in shore position for the entire study area on the same figure; therefore, in all the re- maining plots the shoreline and contour positions are referenced to their final positions as determined in the 1976 survey at each
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