Photo by Mustafa Lazkani - Feb 02, 2016
Scientists estimated the magnitude and timing of each quake by examining soil samples at more than 50 undersea sites between Washington, Oregon and California. Source: UNAVCO. A new study quantifies how these slow-slip events accommodate tectonic plate motion. The Cascadia Subduction Zone off the coast of North America spans from northern California to southern British Columbia. Shallow Earthquakes The shallow earthquakes scenario discusses the effects of earthquakes that occur within the earth's crust. The 1700 Cascadia Subduction Zone Earthquake and Tsunami. Unfortunately our results can’t predict when the next large Cascadia megathrust earthquake will occur. This subduction zone can produce earthquakes as large as magnitude 9 and corresponding tsunamis. Our results provide new insights into how this subduction zone, and possibly others, behaves over geologic time frames of millions of years. The Cascadia Subduction Zone has occasional large earthquakes and frequent slow-slip events. Map of the Pacific North west, showing northwest motion of GPS stations above the locked Cascadia subduction thrust. 10,000 years of Cascadia earthquakes The chart shows all 40 major earthquakes in the Cascadia Subduction Zone that geologists estimate have occurred since 9845 B.C. Posted in Oregon Quakes, Other Washington Quakes, tagged 1700 tsunami, Cascadia Subduction Zone earthquake on January 18, 2010| Leave a Comment » Cascadia Subduction Zone Earthquake Scenario This scenario characterizes the effects of a major subduction earthquake on communities along the Cascadia Subduction Zone, stretching from the Brooks Peninsula on Vancouver Island to Cape Mendocino in northern California. The earthquake became unmistakable when the strong shaking from the “S” (also known as secondary or shear) waves arrived at village after village as the entire fault along the Cascadia Subduction Zone, between Northern California to Vancouver island, ruptured generating fresh seismic waves as the fault continued to unzip for 3-6 terrifying minutes. When a giant earthquake earthquake finally happens, the accumulated strain is released and the deformed part of the overriding plate rapidly heads back seawards, as we see here for the M9 Tohoku earthquake in 2011. Citation : Bartlow, Noel (2020), Faults slip slowly in Cascadia. A series of 8 earthquakes hit the Cascadia Subduction Zone and the Mendocino Fracture zone on March 8, 2020 The biggest quake of the swarm was a M5.8 followed by a M4.9 three hours later.

The very shallow (2.2km or 1.4 miles deep) M5.8 earthquake hit the Mendocino fracture zone on March 8 2020 at around 8pm local time (2:59 UTC).