Earthquake News

A M9 "megathrust" earthquake struck the northwest 318 years ago.

On Friday, the Cascadia Subduction Zone, a fault running from Northern Vancouver Island to Northern California, will be brought to the attention of the northwest as a potential source of the largest natural calamity in North American history.

A megathrust earthquake with a magnitude of 9 occurred 318 years ago. The Washington State Department of Resources blogged about the occasion on Friday.

On January 26, 1700, a Magnitude 9 megathrust earthquake from the Cascadia subduction zone tore a 1,000-kilometer tear right off the coast of North America, shaking and flooding land from British Columbia to California.

The night the Thunderbird and Whale battled was recounted in oral histories of the Quileute and Hoh tribes as shaking mountains, uprooting trees, and filling the area with ocean water.

According to geologists, the incident was the result of the smaller North American plate being pushed under by the Juan de Fuca tectonic plate. The earthquake caused by the violent subduction caused the coast to recede up to 6 feet, and it also generated a tsunami that stretched almost 1,000 feet inland.

The Cascadia earthquake's 4,700-mile path of destruction across the Pacific Ocean, however, allowed researchers to precisely date and time the geologic event to roughly 9 p.m. Jan. 26, 1700.

The Orphan Tsunami of 1700 was documented in Japanese records. It was discovered that coastal forests had been drowned by land subsidence and seawater inundation as a result of the tsunami, which was documented, and red cedar trunk examination by researchers like Brian Atwater of the United States Geological Survey.

Many people are wondering what will happen on the following historical day.

Typically, the Cascadia Subduction Zone ruptures once every 200 to 500 years. It is hard to forecast when a massive earthquake may strike. However, tectonic stresses have been building up in the CSZ for more than three centuries.

According to the Pacific Northwest Seismic Network, if the fault completely ruptures, it might cause another M9 earthquake.

Leaders in emergency management exhort families to have a plan in place in case of an emergency. People should be ready to live alone for seven to ten days.

State officials and geologists have been developing scenarios and practicing emergency exercises in the interim to better understand how a seismic event can develop.

However, according to the Washington DNR, there is still work to be done. According to DNR, Washington lacks an assessment of the seismic risk to important infrastructure and relies on old tsunami inundation maps.

The DNR is advocating for a financial package that will enable the creation of improved maps and security systems for towns.

Ready to retrofit?

Let’s make your home safer

Get a professional evaluation

Call 206-352-5644

Sound Seismic
7543 15th Avenue NW
Seattle, WA 98117

Contractor's license # SOUNDSL836ND

© 2023 Sound Seismic
Seattle Website Design