Steven Dutch, Natural and Applied Sciences, University
of Wisconsin - Green Bay
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The Apostle Islands were so named in the belief there were 12 of them. There are actually at least 20, in case anyone elsewhere loses an apostle and needs an extra. The islands are underlain by Keeweenawan sandstones deposited on top of the volcanic rocks. They're mantled by glacial drift. The nearby Bayfield Peninsula has sandstones around the shoreline but almost no exposure in the interior, which is buried by up to 200 meters of glacial deposits.
Below: sandstone outcrops at the northern end of Madeline Island
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Left and below: views of Bayfield. |
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Looking north from Bayfield: Basswood Island on the right. |
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Looking back toward Bayfield and the Bayfield Peninsula |
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The high island is Oak Island. |
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Raspberry Island in the distance with Oak Island to the right. |
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From near to far (right to left): Hermit Island, Oak Island and Raspberry Island. |
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Devil's Island is the northernmost of the Apostle Islands. The lighthouse dates from 1898. |
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Numerous wave-eroded caves undercut the shoreline. The nearest point in this picture is the northernmost point in Wisconsin. |
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Looking back at Devil's Island |
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Raspberry Island on the left, |
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Left and below: Raspberry Island and its lighthouse |
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Created 23 August 2004, Last Update 06 April 2007
Not an official UW Green Bay site