glacial lake

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glacial lake

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Varved deposit — Varved deposit Varved deposits attributed to sedimentation in Glacial Lake Missoula, Montana, U.S.

A glacial lake is a body of water formed by a variety of glacial-age dams. These lakes can form in depressions created by ice sheets, in eroded scours, or be dammed by ice or glacial sediments. Glaciolacustrine sediments accumulate at the bottom and edges of these lakes.12

Many former glacial lakes, such as the Great Lakes in North America, have shorelines that can indicate their past size and depth. When streams enter a glacial lake, they deposit sediment, forming deltas. The fine-grained sediments from these lakes often form flat plains, with some deposits showing annual layers of silt and clay called varves, which are a result of seasonal changes.2

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Lake Clark National Park and Preserve
…more than a score of glacial lakes on the rim of the Chigmit Mountains, a range located where the Alaska and Aleutian ranges meet. The lake is the headwaters for the most important spawning ground for sockeye, or red, salmon in North America. The park’s great geologic diversity includes jagged…
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…more than a score of glacial lakes on the rim of the Chigmit Mountains, a range located where the Alaska and Aleutian ranges meet. The lake is the headwaters for the most important spawning ground for sockeye, or red, salmon in North America. The park’s great geologic diversity includes jagged…
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river
Falls attributable to constructional processes
…River and formed a vast glacial lake. The lake drained to the south when permitted to do so by periodically occurring ice dams, and torrents of water were released during these breakouts. The water flowed through the Grand Coulee channel and eroded a canyon nearly 300 metres deep. Dry Falls…
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…River and formed a vast glacial lake. The lake drained to the south when permitted to do so by periodically occurring ice dams, and torrents of water were released during these breakouts. The water flowed through the Grand Coulee channel and eroded a canyon nearly 300 metres deep. Dry Falls…
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lake
Basins formed by glaciation
The Pleistocene glaciers, which seem to have affected every continent, were especially effective in North America, Europe, and Asia. The retreat of ice sheets produced basins through mechanical action and through the damming effect of their ice masses at their boundaries.
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The Pleistocene glaciers, which seem to have affected every continent, were especially effective in North America, Europe, and Asia. The retreat of ice sheets produced basins through mechanical action and through the damming effect of their ice masses at their boundaries.
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Quaternary
Lakes
Extensive glacial lakes were formed by a variety of glacial-age dams. They could form simply as pools in the depressions created by the ice sheets, in eroded scours, such as the Great Lakes and the Finger Lakes of New York, by ice dams, or by dams…
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Extensive glacial lakes were formed by a variety of glacial-age dams. They could form simply as pools in the depressions created by the ice sheets, in eroded scours, such as the Great Lakes and the Finger Lakes of New York, by ice dams, or by dams…
Read More