Thursday, October 29, 2015

Lone Rock Point - The Champlain Thrust

Lake Champlain, 2015

Lake Champlain was formed when the last glaciers receded about 12,000 years ago.  It's hard to believe but this whole region was under 1-2 miles of ice.  Shortly after the glaciers receded, this land was below sea level due to the weight of the ice.  This allowed the Atlantic Ocean to flow into the lake via the St Lawrence River, so at one time this was a body of salt water.  The land rebounded above sea level, and over a period of time the salt water was slowly replaced with fresh water.  This photo shows a very famous geological feature known as the Champlain Thrust, a thrust fault where older rocks were forced over younger rocks .

2 comments:

  1. Ed, I always find your knowledge of geology fascinating. Didn't know about the formation of Lake Champlain. Wonder if there is a layer of salt under the lake?

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  2. I agree with TFG... this is interesting and something I have never heard before even though I am familiar with the location and live on one of the Great Lakes which I assume was formed in a similar way.

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