- GeoRef, Copyright 2008, American Geological Institute. Reference includes data from Bibliography and Index of North American Geology, U. S. Geological Survey, Reston, VA, United States
Grain size analyses of 186 samples from the axes of longshore-bars and troughs along the lake shelf at Batchawana Bay and Pancake Bay, Lake Superior, Ontario, show the longshore-bar sands to be better sorted and finer grained than the adjacent shoreward longshore-trough sands. In addition the longshore-bar sands are unimodal and tend to be positively "skewed" whereas the longshore-trough sands may be either unimodal or bimodal and show a tendency towards negative skewness. This would suggest that the longshore-troughs were formed by the action of breaking waves that preferentially set the finer grained particles into motion. These finer grained particles were then moved lakeward by the undertow to form the longshore-bar areas.