Palouse Falls

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Palouse Falls on the Palouse River.

In the Palouse River Canyon just downstream of Palouse Falls, the Sentinel Bluffs flows of the Grand Ronde Formation can be seen on the bottom, covered by the Ginkgo Flow of the Wanapum Basalt.

The Palouse Falls lies on the Palouse River, about 4 miles upstream of the confluence with the Snake River in southeast Washington. The falls are 56 meters in height. The canyon at the falls is 115 meters (377 feet) deep, exposing a large cross-section of the Columbia River Basalt Group. These falls and the canyon downstream comprise an important feature of the channeled scablands created by the great Missoula Floods that swept periodically across eastern Washington and across the Columbia River Plateau during the Pleistocene epoch.^[1][2][3] (Coordinates: 46°44′30″N, 118°14′00″W).

The ancesteral Palouse river flowed through the currently dry Washtucna Coulee to the Columbia River The Palouse Falls and surrounding canyons were created when the Missoula Floods overtopped the south valley wall of the ancesteral Palouse River, diverting it to the current course to the Snake River by erosion of a new channel.^[1][4]

The area is characterized by interconnected and hanging flood-created coulees, cataracts, plunge pools, kolk created potholes, rock benches, buttes and pinacles typical of scablands. Palouse Falls State Park is located at the falls, protecting this part of the uniquely scenic area.^[3]

In 1984 the Franklin County Public Utilities District proposed a 30 meters high dam be constructed upstream of the falls, allowing for a significant hydraulic head for hydro-electricity power generation. This would have provided over 1/3 of the counties power and would have reduced ratepayer charges substantially. However the majority of the ratepayers declined to approve the investment, preserving this geologically significant feature.^[1]

[edit] External links

• Palouse Falls State Park page
• Excellent photo of the falls by Pacific Northwest National Laboratory

[edit] References

1. ^ ^{a b c} Carson, Robert J. and Pogue, Kevin R. (1996). Flood Basalts and Glacier Floods:Roadside Geology of Parts of Walla Walla, Franklin, and Columbia Counties, Washington. Washington State Department of Natural Resources (Washington Division of Geology and Earth Resources Information Circular 90). ISBN none. 
2. ^ Alt, David. Glacial Lake Missoula & its Humongous Floods. Mountain Press Publishing Company. ISBN 0-87842-415-6. 
3. ^ ^{a b} Bjornstad, Bruce (2006). On the Trail of the Ice Age Floods: A Geological Guide to the Mid-Columbia Basin. Keokee Books; Sand Point, Idaho. ISBN 978-1-879628-27-4. 
4. ^ Alt, David and Hyndman, Donald (1984). Roadside Geology of Washington. Mountain Press Publishing Company. ISBN 0-87842-160-2. 

Exploring Ice Age Floods in the Pacific Northwest

| Glacial Lake Missoula | Missoula Floods | Channeled scablands | Grand Coulee | Dry Falls | Drumheller Channels | Columbia River Plateau | Wallula Gap | Touchet Formation | Lake Lewis | Columbia River Gorge | Columbia River Basalt Group | Palouse Falls | Sims Corner Eskers and Kames | Moses Coulee | Withrow Moraine | Crab Creek | Corfu Slide

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