Recent detailed studies of the beach and nearshore environments of eastern Lake Michigan have revealed almost no significant differences compared with similar marine environments, except for the absence of marine tidal fluctuations. The morphology and the processes operating in both areas are remarkably similar; however, the rates at which these processes operate appear to be more rapid in Lake Michigan.

Beach profiles reflect environmental conditions which may or may not be associated with seasonal cycles. Storm conditions yield nearly identical flat profiles in both areas with characteristic lag deposits of heavy minerals in the back-beach zone. Quiescent conditions produce accretionary beaches except when lake levels rise gradually for prolonged periods.

The inner nearshore profile in both Lake Michigan and marine areas is commonly characterized by an ephemeral bar which migrates shoreward and is welded to the beach. The bar forms during the waning phase of a storm and migrates shoreward during low-energy conditions. Migration of the bar generally proceeds more rapidly in Lake Michigan than in tidal areas. The crest of the bar is not exposed in Lake Michigan until welding occurs, whereas, it is exposed during low tide in comparable marine environment.

Farther from shore are relatively stable bars whose number and position are controlled largely by the slope of the nearshore bottom. These features also show generally comparable morphology in both areas, although they seem somewhat less stable in the marine environment.

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