[3] Between Spring Hill and the Ohio state line the Arkona beaches do not show the characteristics normal to those in the Saginaw and Black River valleys.

They are continuous for miles, maintaining a constant level, and then merge into a single set of ridges in the Black River valley.

Initially, Lake Whittlesey's waves began the process of washing the top portion of the Arkona beaches away.

Then a period of deep quiet water allowed fine clays to leave suspension and be deposited among the remaining gravel.

The full strength of the Arkona beach ridges near Cass City and Croswell makes it clear that the ice barrier stood at least 25 miles north, enough distance to allow a heavy on shore surf.

In some places the Arkona beaches stand by the outer border of the Port Huron morainic system.