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Located just north of the famous Gorge Amphitheatre are two enormous lake-filled canyons that appear to feed into the Columbia River.
Unlike canyons in other parts of the world, these weren’t slowly carved by rivers, but quickly excavated by massive floods during the most recent Ice Age.
In fact, the scale of the canyons at Potholes Coulee are so extreme that in 1910 they prompted geologist J Harlen Bretz to develop his theory of Ice Age floods.
Join Nick Zentner as he looks into the clues that Bretz found to come up with his groundbreaking idea.
Support for Nick on the Rocks is provided by Pacific Science Center.
Adam Spiro Brown manages Original Productions at Cascade PBS. He previously ran Lucid Visual Media, an independent production company, creating award-winning documentaries, films and commercials. adam.brown@cascadepbs.org
Adam Spiro Brown manages Original Productions at Cascade PBS. He previously ran Lucid Visual Media, an independent production company, creating award-winning documentaries, films and commercials. adam.brown@cascadepbs.org
