The Great Floods of Glacial Lake Missoula


   One of the objectives of this page is to demonstrate the enormity of scale on which the events refered to as the Great Floods occured. We have also provided information on how and why these floods occured. Finally, we have provided links to other sites regarding these floods and other complementary subject matter.


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CORDILLERAN ICE SHEET - GLACIAL LAKES MISSOULA & COLUMBIA

MAP #1

   Between 15,000 and 12,800 years ago we were in the last throes of the Ice Age and nearing the end of the Pleistocene Epoch. The Cordilleran Ice Sheet expanded southward into northern Washington, Idaho, and Montana.

   A massive sheet of ice 4000 feet thick, the Cordilleran Ice Sheet had three main lobes: The Puget Lobe which scoured out the Puget Sound, the Okanogan Lobe which blocked the Columbia River at the site of the present day Grand Coulee Dam forming Glacial Lake Columbia, and the Purcell Lobe.

melting ice sheet
Melting Ice Sheet
Click here to jump to - The Ice Ages - Mammoth Saga - web page:
For other images of the Purcell Lobe click here:

Page Two: Purcell Lobe Ice Dam Is Breached

Madeby: Kamala Butler, Michael French, Elaine Harman
Last modified: 3/17/1998