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Tremor bursts along NW coastline - Magical Realist - May 22, 2019

Panicking about the "Big One." Then I read thru the article. Whew!

https://komonews.com/news/local/researchers-track-bursts-of-tremors-beneath-seattle-west-coast

"Washington is, once again, on the move.

According to a recent update from the Pacific Northwest Seismic Network, dozens of tremors have been recorded over the past few weeks that "continue to excite and confuse all of us tremor watchers."

The PNSN has been tracking a series of tremors along the West Coast, including throughout the Puget Sound region. And analysts believe it could be representative of a "significant slow slip."

A slow slip isn't quite as fearsome as it might sound — in fact, it's fairly common; it's simply a wave of tiny tremors that are thought to increase stress on locked faults, the areas where tectonic plates cannot move past each other. And scientists don't believe that it's a sign of the oft-talked about "big one."

"That part of the boundary locks up for about 14 months, and then it rumbles and shifts over the course of about a month to let out the strain it's built up," said John Vidale, University of Washington then-professor and director of the UW-based Pacific Northwest Seismic Network (PNSN), in an interview with the SeattlePI regarding the tremors.

"They're all too small to feel. These plates are basically moving half an inch over the course of a couple days, so it kind of jiggles enough that our most sensitive instruments can feel. But people can't."

They've been rocking the Pacific Northwest (often nearly imperceptibly) about every 14 months since at least the 1990s. PNSN's blog posts note that analysts believe that these tremors are outside the normal tremor event, expected around July or August of this year.

"It is far from obvious that there has been a normal, mostly unilateral progression of tremor up or down the region," Steve Malone, PNSN Professor Emeritus, said in a May 16 update for the blog post. "Rather tremor has jumped around with significant batches concentrated in an area for a while and then either moving a bit or dying out."

Malone behind the post say it's possible that the tremors are a result of several tremor events taking place along the fault lines, on different patterns.

"Indeed, central Oregon ETS events have tended to be on about a two year cycle in the past so this is almost a year early if that is what it is. I have not attempted to looks at the GPS data in Oregon myself but suspect that it might show slow slip going on there now."