Canyonlands, Volume II

The late J Harlen Bretz is, for lack of a better description, the patron saint of inland Northwest geology. Early in his long career, he had the audacity to propose his explanation for the palisade-walled canyons, braided dry channels, and majestic buttes that characterize much of the lower Columbia Basin. Bretz originally referred to the catastrophic event as the “Spokane Flood” because it looked as though present-day Spokane had been the source, or at least the spigot, for a massive torrent that could explain the terrain.

Today we often refer to it as the ancient Lake Missoula floods, caused when a lake of glacial meltwater, half the size of Lake Michigan, broke though its ice dam. This happened several times during the most recent ice age, and perhaps as recently as 13,000 years ago. When these all but unimaginable floods occurred, the rampaging waves of water and ice suddenly headed toward present-day Pasco were hundreds of feet deep and traveled at speeds approaching 80 miles an hour.

About eastern Washington’s scabland canyons, Bretz wrote that the resulting “labyrinthine” pattern of ‘bare rock knobs and buttes” is “unlike any other land surfaces on the earth.”

It took Bretz nearly a half century to see his theory validated by, among other things, satellite imagery. I don’t have nearly that much time left, but even if I did I doubt I could spend enough of it in the hauntingly quiet and beautiful corners of this evident cataclysm. In the meantime, here’s Volume II. Volume I was published last year.—Tim Connor

 

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