Friday, July 12, 2019

4.6, 3.5 Quakes Hit Puget Sound Area, 6.0 Hits New Guinea


4.6 quake rattles Puget Sound area; 3.5 aftershock minutes later


Many residents across the Puget Sound area were jolted awake early Friday morning by a pair of earthquakes that struck the North Sound.
The first quake struck at 2:51 a.m. and was measured at a magnitude of 4.6, according to the Pacific Northwest Seismic Network. It was centered about 2 miles northwest of Monroe and was about 13 miles deep.A 3.5 aftershock hit three minutes later in the same area, according to PNSN, centered about a mile northwest of the first quake and about 5 miles deeper.
It was felt everywhere from Vancouver, BC to the north, Olympia to the south and as far east as Yakima and Wenatchee, according to seismologist Bill Steele with PNSN.

There are no initial reports of any damages or injuries, and none would really be expected with a quake of this magnitude. 
"You experience moderate shaking -- you definitely know things are shaking," Steele said. "Something that might be teetering on a shelf might fall over but we wouldn't expect structural damage."
Hundreds who felt the quake flooded the Snohomish County 911 call center.
"Our partners @911Snohomish received 403 calls between 2 a.m and 4 a.m. today" after the quakes, Snohomish County emergency managers tweeted. "Normal volume is about 50 calls an hour. Reminder: After a quake, only call 911 to report emergencies."
Those who didn't make a call instead filled social media talking about the quake.
"About 10 seconds before the earthquake hit, my dog ran into my room and jumped on my bed," said Ben in Everett. "The bed started shaking and a (large Game of Thrones) picture came off (my wall) and hit me and my dog -- scared us pretty good!"
"I was at my daughter's work in Everett and we heard a growling noise followed by the ground and building shaking," says @mikeykg05 on Twitter. "Felt and sounded so much different than the one I experienced in 2001."
"We live in Everett - we definitely felt a rumble and shaking that lasted between 5 - 10 seconds. We also felt the aftershock," Kathy Koss wrote on Facebook. "I checked the house for damage and it seems we had nothing fall or break. We're feeling pretty lucky this morning and hopeful this is the end of this event. "

A number of witnesses have reported on not just the shaking, but the sound the quake made.
But the shaking might not be done yet. There have already been a handful of small aftershocks and Steele says more are expected.
"There will be more (aftershocks)," Steele said. "In fact we're in the process of processing those smaller ones."
He added that there is the possibility these quakes may lead to a larger one:
"There is a very small chance that when you have an earthquake sequence like this going you may end up triggering a larger earthquake and then this magnitude 4.6 becomes a foreshock to that larger event," Steele said. "That's a pretty rare occurrence, but it does happen."



Credit, Southern Californian Seismic Network

A mag 6.0 - 174km N of Arawa, Papua New Guinea is the 6th major quake of July, all 6 have occurred around the Pacific Ring Of Fire including the magnitude 7.1 and 6.4 in Southern California.

Meanwhile, what is being called "swarmageddon" by the locals, the number of aftershocks since the powerful mag 7.1 quake has now reached almost 11,000, however, the swarm in the last 24 hours is showing signs of reduction with a total of 1,600, see screenshot above.

The total number of major quakes (mag 6+) so far this year is an impressive 83, the same period in 2018 delivered just 46 and the same period in 2017 delivered 49, 2016: 75, 2015: 79, 2014: 98, 2013: 77, 2012: 74, 2011: 135, which of course was the year of the Fukushima disaster Japan which suffered more than 70 mag 6+ aftershocks.




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