Smithsonian Magazine:
"Brian Atwater paddled a battered aluminum canoe up the CopalisRiver, pushed along by a rising Pacific tide. At this point, a 130-mile drive from Seattle, the 100-foot-wide river wound through wide salt marshes fringed with conifers growing on high ground. The scene, softened by gray winter light and drizzle, was so quiet one could hear the whisper of surf a mile away. But then Atwater rounded a bend, and a vision of sudden, violent destruction appeared before him: stranded in the middle of a marsh were dozens of towering western red cedars, weathered like old bones, their gnarly, hollow trunks wide enough to crawl into. 'The ghost forest,' Atwater said, pulling his paddle from the water. 'Earthquake victims.'
"Atwater beached the canoe and got out to walk among the spectral giants, relics of the last great Pacific Northwest earthquake. The quake generated a vast tsunami that inundated parts of the West Coast and surged across the Pacific, flooding villages some 4,500 miles away in Japan. It was as powerful as the one that killed more than 220,000 people in the Indian Ocean in December. The cedars died after saltwater rushed in, poisoning their roots but leaving their trunks standing. This quake is not noted in any written North American record, but it is clearly written in the earth. The ghost forest stands as perhaps the most conspicuous and haunting warning that it has happened here before—and it will surely happen here again. 'When I started out, a lot of these dangers were not all that clear,' says Atwater, a geologist for the U.S. Geological Survey (USGS) who specializes in the science of paleoseismology, or the study of earthquakes past. 'If you look at what we know now, it beats you over the head.'
'In one of the more remarkable feats of modern geoscience, researchers have pinpointed the date, hour and size of the cataclysm that killed these cedars. In Japan, officials had recorded an 'orphan' tsunami—unconnected with any felt earthquake— with waves up to ten feet high along 600 miles of the Honshu coast at midnight, January 27, 1700. Several years ago, Japanese researchers, by estimating the tsunami’s speed, path and other properties, concluded that it was triggered by a magnitude 9 earthquake that warped the seafloor off the Washington coast at 9 p.m. Pacific Standard Time on January 26, 1700. To confirm it, U.S. researchers found a few old trees of known age that had survived the earthquake and compared their tree rings with the rings of the ghost forest cedars. The trees had indeed died just before the growing season of 1700.'"
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