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Discovery Day: Introduction to Glacial Lake Missoula Tour
May 12, 2018 @ 9:00 am - 6:00 pm$15 – $20
Introduction to Glacial Lake Missoula Tour
This trip is SOLD OUT. Please check back in the fall and next spring for future Glacial Lake Missoula field trips.
Learn about Glacial Lake Missoula and see beautiful territory on this special bus tour led by members of the Glacial Lake Missoula Chapter of the Ice Age Floods Institute.
We will stop at 7-10 major geologic features related to Glacial Lake Missoula and the ice age floods. Chapter members will also narrate stories about the discovery of the evidence and point out interesting land forms as we drive. See the giant ripples of the Camas Prairie, gulch fills along the Flathead river, kolks, rhythmites, and more!
We will be stopping for lunch at Quinn’s hot springs. View their menu here.
Please bring: Clothes appropriate for Montana’s changing weather; Good walking shoes or boots; Water
Snacks are provided.
Transportation: MNHC bus
Cost: $15/$20 members/non-members
The tour will follow a new map which can be downloaded and is accessible on smart phones (even in areas without cell phone coverage). The new map will be available in print form in a revised brochure which will be ready for distribution later this spring! It will also be available on the Glacial Lake Missoula page of the ice Age Floods Institute website, iafi.org.
During the latter stages of the last ice ages, 18,000 to 12,000 years ago, a large mass of glacial ice blocked the path of the Clark Fork River at the Montana/Idaho border. As the waters rose behind this 2,000 foot high, 35-mile wide ice dam, they flooded the valleys of Western Montana. At its greatest extent the resulting lake—Glacial Lake Missoula—stretched east to Drummond, as far south as Darby, and north into the Flathead and Blackfoot river valleys.
Periodically, the dam would fail. The failure was often catastrophic, resulting in a large flood of ice-filled water that would rush down the Columbia River drainage across northern Idaho, eastern Washington, through the Columbia River Gorge, into Oregon’s Willamette Valley, and finally draining into the Pacific Ocean near Astoria, Oregon. The lake at its maximum height and extent contributed more than 500 cubic miles of water to the largest of these floods which would drain in a few days.