Seattle Is Vulnerable to Earthquakes
When a massive quake rattles the Pacific Northwest, everything from books to canisters of flour in kitchen cabinets will be shaken loose and hurled across rooms. But what if multiple faults ruptured essentially simultaneously?
That’s what happened in the region 1,100 years ago, according to a study published this week in Science Advances. Scientists used tree ring data to fairly precisely pin down the tumult to a six-month period between 923 and 924 C.E.
1. 4.3 Magnitude Earthquake Near Marrowstone
A 4.3 magnitude earthquake shook western Washington on Sunday evening, unsettling residents and rattling furniture. While there were no reports of serious damage or injuries, the quake serves as a reminder that Seattle is vulnerable to seismic activity and that preparedness is key.
The earthquake occurred near Marrowstone, and had a depth of 57 kilometers. It was felt throughout the Puget Sound region, with varying degrees of shaking. Communities closest to the epicenter experienced stronger tremors, with buildings swaying and water in bottles moving. Those further away experienced less intense tremors, with some swaying of furniture and rattling of loose items.
The quake was caused by complex tectonic interactions in the Pacific Northwest. The Juan de Fuca Plate is subducting beneath the North American Plate, creating a build-up of pressure and stress that can eventually be released in earthquakes. This geological feature is known as the Cascadia Subduction Zone. It’s the same fault that’s been responsible for whole forests sweeping into lakebeds in the past, and could be responsible for a devastating tsunami in the future.
2. 4.3 Magnitude Earthquake Near Port Townsend
A 4.3 magnitude earthquake hit Western Washington Sunday evening, shaking buildings and rattling homes. It had a depth of 57 kilometers. It was centered near Marrowstone Island and was felt throughout the Puget Sound area.
Tess Teel of Port Townsend told KUOW she felt the quake while making a pot of coffee. She said, “It was pretty strong but not anything that I would consider a major earthquake.”
The quake was also felt as far north as Bangor Trident Base and as south as Centralia in Island County. It was a moderate intensity quake, and the US Geological Survey’s ShakeAlert system didn’t activate because it was below magnitude 4.5.
The quake’s location shows it happened in a region with a lot of seismic activity. Western Washington sits at the boundary of the Juan de Fuca and North American plates, which are rumbling together, creating a potentially dangerous fault zone. But that doesn’t mean a massive earthquake is imminent. Scientists have found a link between the Seattle and Saddle Mountain fault zones, and if they both rupture at once it could cause much more damage.
3. 4.3 Magnitude Earthquake Near Bellingham
MUKILTEO, WA—Puget Sound residents were jolted by a shallow magnitude 4.3 earthquake late Sunday evening. According to the United States Geological Survey, the quake had an epicenter just south of Port Townsend. KOMO reports that people felt the tremors as far as Seattle. No tsunami warnings were issued.
Scientists say the quake is not likely to cause major damage. But it is a reminder that the region has many faults and that large earthquakes are possible.
One fault zone runs directly under downtown Seattle. If it ruptures, it could create a devastating wave that would destroy homes and businesses and bury and kill thousands of people.
Earthquakes are fairly common in Washington state, but most are too small to feel. Learn how to make your home or business more earthquake-ready with a free seismic assessment. CLICK HERE to request yours. It only takes a few minutes! Interested in learning more? Get your FREE Earthquake Risk Assessment Today!
4. 4.3 Magnitude Earthquake Near Snohomish County
The latest earthquake in Washington is a reminder that it is important to be prepared. Make sure you have a plan, secure heavy items, and know what to do if a big one hits.
KOMO News viewers feel the 4.3 magnitude quake in western Washington on Sunday evening. The Pacific Northwest Seismic Network says the quake had an epicenter near Marrowstone Island. It was felt from Victoria, Canada, to Olympia. There are no reports of damage or injuries.
Earthquakes happen in Washington often, but it’s rare for them to be as strong as this one. The state has dozens of faults and fault zones, including the Seattle Fault and the Cascadia Subduction Zone, which could cause a large earthquake. Scientists are researching how to better predict the size and time of the next major quake in the area. They use a technique called seismic tomography to study the interior of the earth and find out what’s happening beneath our feet.