The 'Champlain Sea' was a temporary inlet of the Atlantic Ocean, created by the retreating
glaciers during the close of the last
ice age. The Sea once included lands in what are now the
Canadian provinces of
Quebec and
Ontario, as well as parts of the
American states of
New York and
Vermont.
The mass of ice from the continental ice sheets had depressed the rock beneath it over millennia, causing it to rebound once the ice melted. This process is gradual and known as
isostatic rebound, which can be observed today in the northern
Baltic Sea and
Hudson Bay. While the rock was still depressed, the
Saint Lawrence and
Ottawa River valleys, as well as modern
Lake Champlain, were below sea level and flooded once the ice no longer prevented the ocean from flowing in to the region.
The sea lasted from about 13,000 years ago to about 10,000 years ago and was continuously shrinking during that time, since the rebounding continent was slowly rising above sea level. At its peak, the sea extended inland as far south as
Lake Champlain and somewhat farther west than the site of
Ottawa, Ontario. The remaining glaciers fed the sea during that time, making it more
brackish than typical seawater. It is estimated that the sea was as much as 150 meters above the level of today's Saint Lawrence and Ottawa Rivers.
Modern evidence of the sea can be seen in the form of whale fossils that have been found near the cities of Ottawa, Ontario, and
Montreal, Quebec, and the existence of ancient shorelines in the former coastal regions.
External links
★
Paleoceanography of the Champlain Sea
★
Champlain Sea fossils
★
History of the Champlain Sea.
★
Charlotte, The Vermont Whale
★ http://www.lesaventuresdupatrimoine.com/joly/gardiens/gar14.html
★ http://www.civilization.ca/cmc/archeo/kichisibi/champlain/f3-0.htm
★ http://www.ggl.ulaval.ca/personnel/bourque/s3/retrait.glaces.html