There are 21 Apostle Islands in Lake Superior (on the southwest corner), which were named by French missionaries after the 12 apostles (they clearly couldn't see all 21 islands). The islands were formed by wind wave erosion between ice ages, and were glaciated repeatedly after that. Terraces and wave cut platforms suggest that water levels used to be higher in Lake Superior. Of particular interest are the sea caves found on many of the islands. The Devils Island Formation geology is a red sandstone that formed from rivers depositing sediment thousands of years ago. The sea caves form when waves erode and undercut the base of the cliffs.
RSS Feed
