Geological Survey The Channeled Scablands of Eastern Washington

THE CHANNELED SCABLANDS OF EASTERN WASHINGTON
—The Geologic Story of the Spokane Flood—

Electric City—Grand Coulee, Washington

A traveler entering the State of Washington from the East crosses a flat-to-rolling country side of deep, fertile soil commonly sown with wheat. Continuing westward, he abruptly enters a deeply scarred land of bare black rock cut by labyrinthine canyons and channels, plunge pools and rock basins, cascade and cataract ledges, and displaying ragged buttes and cliffs, alcoves, immense gravel bars, and giant ripple marks. The traveler has reached the starkly scenic "Channeled Scablands," and this dramatic change in the landscape may well cause him to wonder "what happened here?" The answer—the greatest flood documented by man.

This publication, summarizing the sequence of geologic events that culminated in the so-called "Spokane Flood," was prepared in response to a general interest in geology and a particular interest in the origin of the Scablands often expressed by those crossing the State of Washington.

Fig. 1.—Soil-covered land sown with wheat is shown on the right; the Channeled scablands is on the left.