The Missoula Floods and the Scablands Heretic

In 1923, a University of Chicago geologist named J Harlen Bretz presented a radical idea. He had spent two years exploring a barren region in eastern Washington he called the 'Channeled Scablands.' It was a bizarre landscape, scoured clean of its soil, with massive canyons called coulees sitting high above any river. Car-sized boulders, called erratics, were scattered hundreds of kilometers from their origin. Bretz argued that only one thing could explain this: a single, short-lived flood of 'appalling' proportions. But in the 1920s, geology was ruled by uniformitarianism—the belief that all change is slow and gradual. Bretz's catastrophic flood sounded like heresy, and it was a challenge that the scientific establishment would not ignore.