PORTLAND, Ore. (KTVZ) — Around 9 p.m. on January 26th, 1700, a powerful magnitude 9.0 earthquake struck along the Cascadia Subduction Zone, which extends from Vancouver Island in British Columbia to Cape Mendocino in California.
This earthquake released energy equivalent to about two billion tons of TNT, leading to significant impacts along the Oregon coast, the effects of which are preserved in the oral traditions of native communities and evident in the landscape.
Damage from a CSZ earthquake would affect the entire region, causing several minutes of intense shaking along the Oregon coast, tsunamis tens of feet high, and shaking extending through the Cascade Range, with lesser impacts in eastern Oregon.
The global study of earthquakes has revealed that they are cyclical in nature, driven by the movement and interactions of tectonic plates. As such, the CSZ, where the 1700 earthquake occurred, has been accumulating energy since the last event that will be released in future earthquakes.