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Potholes - Page 3

Channeled Scablands. Such an unappealing name. Nevertheless, it's an apt description for this area of central Washington. The end-of-the-ice-age floods scoured the country side, scooping out basins and hollows in the underlying basalt, while depositing silt, sand, gravel and other material willy-nilly, hither and yon.

Looking south over the Channled Scablands.
The resulting landscape, once the final flood waters had spent themselves, left the viewer confronted with a series of channels filled with numerous small lakes and geologic trash scattered everywhere.

However, one era's trash is another era's treasure. Geologists who studied these areas in the first half of the 20th century were confounded by what they saw. The accepted theory was that a large glacier had caused the present day landscape; this fitted nicely with the overall notion that geological changes happened slowly and uniformly everywhere on the planet.

Looking south over one of the Potholes.
The unaccepted theory, put forth by J. Harlen Bretz, was that a series of catastrophic floods had swept the region, leaving their mark everywhere over thousands of square miles. By 1952, Bretz had amassed so much evidence for his "catastrophic" theory that it could no longer be ignored. In 1965, when he was 82 years old, the International Geological Congress validated his work and the floods that he theorized about for 40 years became the accepted explanation for many of the surface features seen today in eastern and central Washington, down the Columbia Gorge to the Pacific and as far south as Eugene, Oregon.

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