The Megaquake That Could Break America’s West Coast - CASCADIA 1700

The Megaquake That Could Break America’s West Coast - CASCADIA 1700 On a winter night in 1700, a tsunami swept into fishing villages along the coast of Japan. Houses were swept away, a fire broke out, and officials carefully wrote everything down. But no one in Japan had felt an earthquake. The wave had no parent. It was an orphan. Almost 300 years later, scientists found the answer on the other side of the Pacific: ghost forests of dead cedars in Washington and Oregon, buried soils covered by tsunami sand, and the stories of Native nations who remembered a great shaking on a winter night. Together they point to one fault: the Cascadia Subduction Zone, a 700-mile megathrust fault off the coast of Washington, Oregon, and northern California. The last great Cascadia earthquake struck on January 26, 1700, at around 9 PM, with an estimated magnitude of about 9. According to the USGS, there is roughly a 10 to 15 percent chance of another magnitude 9 in the next 50 years. When it happens, the shaking could last three to five minutes, and the first tsunami waves could reach parts of the coast in 15 to 30 minutes. CHAPTERS 0:00 The wave with no earthquake 1:54 The orphan tsunami of 1700 4:36 The ghost forests 7:59 The scientific detective story 11:49 America's most dangerous fault 15:14 Fifteen minutes 19:20 The clock is still running SOURCES & ARCHIVE MATERIAL U.S. Geological Survey: "The Orphan Tsunami of 1700 - Japanese Clues to a Parent Earthquake in North America" (Professional Paper 1707), USGS Fact Sheet 2025-3050 (Cascadia earthquake probabilities), USGS earthquake event page for the 1700 Cascadia earthquake, Pacific Northwest Seismic Network, NOAA / Pacific Tsunami Warning Center animations, USGS ShakeAlert, U.S. Navy and National Guard photos, Library of Congress, Wikimedia Commons (public domain). Japanese woodblock prints by Hokusai and Hiroshige (public domain). Additional photos (CC BY-SA): "Neskowin Ghost Forest" by Chrahp (CC BY-SA 4.0); "Portagetoday" by Beeblebrox (CC BY-SA 3.0), via Wikimedia Commons. MUSIC "Darkling" Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 4.0 License http:/creativecommons.org/licenses/by/4.0/ "Ossuary 6 - Air" Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 4.0 License http:/creativecommons.org/licenses/by/4.0/ "Static Motion" Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 4.0 License http:/creativecommons.org/licenses/by/4.0/ "Scissors" Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 4.0 License http:/creativecommons.org/licenses/by/4.0/ "Lightless Dawn" Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 4.0 License http:/creativecommons.org/licenses/by/4.0/ Subscribe for more true stories about the hidden forces that shape America. This video is a documentary based on USGS research, historical records and published scientific estimates. The future earthquake scenario is a scientific projection, not a prediction of a specific date. Some scenes use simulations, artwork or representative footage. #Cascadia #Earthquake #Tsunami