Two video programs on one DVD! The Great Floods: Cataclysms of the Ice Age
The Pacific Northwest was the stage for one of the 20th century's great mysteries. The unlikely evidence: a maze of enormous empty river canyons, bolder-strewn valleys, giant ripple marks, and the skeletal remains of the world's largest waterfall - all geologically fresh, yet sitting high and dry, far from any source of water. In 1923, geologist J. Harlen Bretz proposed a catastrophic flood as their genesis, igniting a debate that raged for nearly half a century. "The Great Floods" tracks the clues leading to the final verdict that revolutionized geologic thinking: the Ice Age floods. Produced by Washington State University in cooperation with Lake Roosevelt National Recreation Area. 13 minutes.Ice Age Floods: Catastrophic Transformation of the West.
Spectacular floods changed the landscape of Oregon and Washington some 17,000 yeras ago, when Ice Age glacial dams near present day Missoula, Montana broke apart and unleashed an inland sea. The powerful flood - what geologists believe was the greatest moving body of water in the Earth's history - tore open the landscape of eastern Washington, merged with the Columbia River, and left what is now Portland, Oregon under 400 feet of water. The greatest floods carried fertile eastern Washington soil 600 miles to Oregon's Willamette Valley, forming the base for the thriving agriculture in the valley today. Made possible through partnership with Oregon Public Broadcasting. 28 minutes.
Features: 41 minutes. 1994 and 1998.