Please join geologists, Duane and Ruth Braun, for a talk about the geological makeup of Mount Desert Island on Tuesday evening, May 6, 5:30pm at Southwest Harbor Public Library.
Have you ever wondered about the geologic origin of Mount Desert Island? How it was put together? What effect the glaciers had on the current landscape? The Brauns will take us on a geologic history tour. Their talk will begin around a billion years ago when MDI was attached to the super continent, Gondwana. It eventually split from Gondwana and attached itself to North America. MDI itself experienced three major geologic events, which resulted in the formation of ten different rock units that now make up MDI. The oldest of these formations is the beautiful Ellsworth schist. Most of the rock on MDI formed around 420 million years ago as magma intrusions fed a huge volcanic crater the size of MDI. Two miles of rock have been eroded since then to form the present landscape. Over the last 2.5 million years glaciers have repeatedly covered the Island with up to 5,000 feet of ice. When the glaciers retreated they left behind a number of different deposits and landforms helping to create a beautiful and striking landscape.
For more information, call the Library at 244-7065.