16 June 2014

A "Swarm" of Earthquakes

As Paul Harvey used to say, "Here is a strange."

 

A magnitude 5.7 earthquake early this morning near Noatak marks the fifth quake of exactly that size measured around the northwest Alaska village since April, according to the Alaska Earthquake Information Center. The center, at the University of Alaska Fairbanks, has also measured hundreds of smaller aftershocks in the area, some measuring magnitude 4 or greater.

The seismic activity is about 12 miles northeast of Noatak, a village of about 500 people near the Chukchi Sea coast north of Kotzebue, and 25 miles south of the Red Dog Mine.

The unusual "swarm" of earthquakes near Noatak has left residents on edge in the remote region.
There have been no reports no injuries or significant damage, but the shaking left cracks in older buildings on stilts in the village, according to Natasha Ruppert, a seismologist at the center.

Residents are frightened by these fairly strong quakes occurring every two to four weeks, Ruppert said. "People were really concerned, and they still are."

Ruppert and a seismic technician traveled to the village a month ago to meet with residents, local officials and students. The tech installed a seismic sensor there and in Kotzebue. The tectonics of the region are not well-studied, Ruppert said.

The earthquake "swarm" began on April 18 with two magnitude 5.7 quakes 12 minutes apart. Three more of the same magnitude came on May 3, June 9 and today, along with over 300 smaller quakes.
Monday's quake came just after 4 a.m. A magnitude 4.2 earthquake preceded it by one minute, the center said. Numerous magnitude 3 and 4 aftershocks are expected.

There is no immediate explanation for the swarm of quakes and they are not connected to the mine, Ruppert said. There are active seismic faults south of the area, on the Seward Peninsula, but only long-inactive faults in the immediate area, she said.

12 comments:

Old NFO said...

I'd say 'something' woke up those inactive faults....

Rev. Paul said...

Absolutely. The only question is "what".

Cathy said...

Whoa.

That's a pretty good shake!

Rev. Paul said...

A 5.7 is respectable, Cathy. It'll get your attention, too. :)

joated said...

I blame Godzilla!

Sandy said...

Rev. Paul,

Those earthquakes are something else. We've had them daily here due to fracking. Today, they were 3.

These are not as bad as the ones we experiences living in Japan when I was a kid.

Rev. Paul said...

joated, I think you're on to something!

Sandy, understood. I noted the article states that there's no known reason for these, though.

threecollie said...

The itty bitty ones we get make me nervous....let alone a whole swarm.

ProudHillbilly said...

Well, there is either good news or bad news. The good: stress is being relieved along the faults with several smaller quakes rather than a big one and it will just sort of shake itself out and then quiet down. The bad: the swarm indicates increasing stress and the quakes aren't enough to relieve it, meaning there might be a honkin' big shift at some point in the future.

armedlaughing said...

As long as it's not a murder of earthquakes, you're okay...

gfa

Rev. Paul said...

threecollie, I hear you. It's a weird feeling when you realize that the earth is moving. The only "safe" place to be is in mid-air ... and that presupposes that there won't be any damage to the runways. :)

PH, many of us in AK are well-acquainted with 'quakes, and the tectonic science. The folks out there on our west coast don't usually get them, and that's part of why they're making a fuss about it.

Rev. Paul said...

Guffaw, uh ... yeah. What you said. Heh.