<P> It is suggested that the 1700 earthquake took place at about 21: 00 on January 26, 1700 (NS). Although there are no written records for the region from the time, the timing of earthquake has been inferred from Japanese records of a tsunami that does not correlate with any other Pacific Rim earthquake . The Japanese records exist primarily in the prefecture of Iwate, in communities such as Tsugaruishi, Kuwagasaki and Ōtsuchi . </P> <P> The most important clue linking the tsunami in Japan and the earthquake in the Pacific Northwest comes from studies of tree rings (dendrochronology), which show that several "ghost forests" of red cedar trees in Oregon and Washington, killed by lowering of coastal forests into the tidal zone by the earthquake, have outermost growth rings that formed in 1699, the last growing season before the tsunami . This includes both inland stands of trees, such as one on the Copalis River in Washington, and pockets of tree stumps that are now under the ocean surface and become exposed only at low tide . </P> <P> Sediment layers in these locations demonstrate a pattern consistent with seismic and tsunami events occurring around this time . Core samples from the ocean floor, as well as debris samples from some earthquake - induced landslides in the Pacific Northwest, also support this timing of the event . Archaeological research in the region has uncovered evidence of several coastal villages having been flooded and abandoned around 1700 . </P> <P> Local Native American and First Nations groups residing in Cascadia did not have a written tradition of record - keeping, so the event was not documented locally like the Japanese tsunami . However, numerous oral traditions describing a great earthquake and tsunami - like flooding exist among indigenous coastal peoples from British Columbia to Northern California . These do not specify an exact date, and not all earthquake stories in the region can be definitively isolated as referring to the 1700 quake in particular; however, virtually all of the native peoples in the region have at least one traditional story of an event much stronger and more destructive than any other that their community had ever experienced . </P>

When did the last tsunami hit the oregon coast