Free Republic

A larger Mag 6.4 earthquake tripped offshore of Seattle WA last night. It is the latest in a small swarm of Mag 4, Mag 5, and now Mag 6 earthquakes that began two days in the Cascadia Fault Zone that runs from British Columbia south to Northern California. The Cascadia Fault is regularly hit with Mag 8 (average interval 350 years) and occainsional Mag 9 (interval about 580 years) earthquakes. The last very large killed thousands of native Indians up and down the Washington and Oregon coastline in January 1700, and hundreds more in Japan from its tsunami waves.

The last huge earthquake, the last really “Big One” to hit the Pacific Northwest Coast, struck around 9 p.m. on Jan. 26, 1700 — 321 years ago. Called Cascadia, the magnitude 9.0 quake caused the entire Pacific Northwest coastline to suddenly drop 3 to 6 feet and sent a 33-foot high tsunami across the ocean to Japan. The last huge earthquake, the last really “Big One” to hit the Pacific Northwest Coast, struck around 9 p.m. on Jan. 26, 1700 — 321 years ago. Called Cascadia, the magnitude 9.0 quake caused the entire Pacific Northwest coastline to suddenly drop 3...

The Cascadia fault, a 600-mile-long collision between two chunks of the earth's crust off the Pacific Northwest coast, has been quiet for a long time, and that is not a comforting fact. Major earthquakes occur somewhere in the world every year or two. Catastrophic tsunamis - giant waves generated by undersea earthquakes or landslides - strike less often, and some of the largest of tsunamis originate in places that do not, at first glance, appear particularly treacherous. The devastating tsunamis created Dec. 26 by a magnitude 9.0 earthquake that killed as many as 150,000 people on the shores of the...

Source: University Of Washington Date: 2003-10-31 Japanese Shipwreck Adds To Evidence Of Great Cascadia Earthquake In 1700 Evidence has mounted for nearly 20 years that a great earthquake ripped the seafloor off the Washington coast in 1700, long before there were any written records in the region. Now, a newly authenticated record of a fatal shipwreck in Japan has added an intriguing clue. Written records collected from villages along a 500-mile stretch of the main Japanese island of Honshu show the coast was hit by a series of waves, collectively called a tsunami, on Jan. 28, 1700. Because no Japanese...

At 9PM on January 26, 1700 one of the world's largest earthquakes occurred along the west coast of North America. The undersea Cascadia thrust fault ruptured along a 680 mile length, from mid Vancouver Island to northern California in a great earthquake, producing tremendous shaking and a huge tsunami that swept across the Pacific. The Cascadia fault is the boundary between two of the Earth's tectonic plates: the smaller offshore Juan de Fuca plate that is sliding under the much larger North American plate. The earthquake also left unmistakable signatures in the geological record as the outer coastal regions subsided...