Missoula floods

E95487

The Missoula floods were a series of cataclysmic Ice Age glacial outburst floods that repeatedly swept across the Pacific Northwest, dramatically reshaping the landscape of what is now Washington, Oregon, Idaho, and Montana.


Statements (50)
Predicate Object
instanceOf cataclysmic flood event
glacial lake outburst flood
paleoflood
alsoKnownAs Bretz floods
Missoula Flood
Spokane Floods
associatedWith Cordilleran Ice Sheet
Glacial Lake Columbia
Lake Lewis
cause failure of the ice dam of Glacial Lake Missoula
repeated ice-dam collapses on the Clark Fork River
created coulees
dry falls
giant current ripples
hanging valleys
large gravel bars
pothole cataracts
deposited erratic boulders transported on icebergs
thick layers of silt in the Willamette Valley
endTime approximately 13,000 years ago
evidenceFoundIn Columbia River Gorge
eastern Washington
northern Idaho
western Montana
hasOrigin Clark Fork River valley
Glacial Lake Missoula
influenced regional drainage patterns of the Columbia River system
soil distribution in eastern Washington and Oregon
maximumDischarge on the order of 10 million cubic meters per second
maximumLakeDepth over 600 meters at the ice dam
maximumLakeVolume approximately 2,100 cubic kilometers
partOf Quaternary glacial history of North America
recognizedAs one of the largest known freshwater floods on Earth
recurrence dozens of separate flood events
possibly more than 40 major floods
reshaped Channeled Scablands
Columbia River Gorge
Snake River Plain features
Spokane River valley
Willamette Valley
startTime approximately 18,000 years ago
studiedBy J Harlen Bretz
timePeriod Late Wisconsin glaciation
Pleistocene epoch
tookPlaceIn Idaho
Montana
Oregon
Pacific Northwest
United States NERFINISHED
Washington (state)

Referenced by (8)
Subject (surface form when different) Predicate
Missoula floods ("Missoula Flood")
Missoula floods ("Spokane Floods")
Missoula floods ("Bretz floods")
alsoKnownAs
Channeled Scablands ("Missoula Floods")
Channeled Scablands ("Ice Age floods")
formedBy
Channeled Scablands ("Spokane Floods")
associatedWith
Columbia Plateau
erodedBy
Columbia National Wildlife Refuge ("Missoula Floods")
formedByGeologicalProcess

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