Seismic Activity? How Bad IS it? (Anchorage, Delta Junction: earthquake, living in, military)

[SirLancelot911]

An interesting question my wife brought up that I had never considered yet with Alaska is the seismic activity. We have some family in Southern California and they complain of semi-frequent tremors that can be felt. I read up on Alaska and have a few "concerns" (for lack of a better word).

Obviously there was the catostrophic quake in '64. I knew already the "Ring of Fire" goes right through Alaska. I read yesterday however that it is the most seismically active place in the entire country with frequent quakes. How realiastic is that? Do you feel tremors frequently? When you do is it the "hmmm, did I just feel something slight" kind of reaction, or the "honey, put the pictures back on the wall, please" reaction?

Is it as bad as online resources make it out to be? I'm from Seattle where they've been saying for as long as I can remember that we're long overdue for "the big one". That said, I know that nowhere is earthquake proof. Are frequent tremors/quakes something I'd really have to get used to in Anchorage though?

[LittleJazzyP]

I've felt one since I've been here. It made the monitor on my computer at work wobble a little bit. I know of a tremor a few months before that my friends said they felt, but I was on the bus when it happened and didn't notice it.

I've never heard anyone say they had to "get used to" seismic activity here. If you are going to worry, I suggest you go back to worrying about the weather.

[tigre79]

I've felt a couple in the year and a half I've lived here. Just minor stuff. Obviously they can be a big deal, but it's not an everyday thing that's going to be knocking all your fragile stuff all over the place.

[gobrien]

The quakes usually just feel like somebody bumped the couch, although if you get a job in a multi-storied building built on rollers, you will feel the earthquake more.

[Glitch]

Originally Posted by SirLancelot911

An interesting question my wife brought up that I had never considered yet with Alaska is the seismic activity. We have some family in Southern California and they complain of semi-frequent tremors that can be felt. I read up on Alaska and have a few "concerns" (for lack of a better word).

Obviously there was the catostrophic quake in '64. I knew already the "Ring of Fire" goes right through Alaska. I read yesterday however that it is the most seismically active place in the entire country with frequent quakes. How realiastic is that? Do you feel tremors frequently? When you do is it the "hmmm, did I just feel something slight" kind of reaction, or the "honey, put the pictures back on the wall, please" reaction?

Is it as bad as online resources make it out to be? I'm from Seattle where they've been saying for as long as I can remember that we're long overdue for "the big one". That said, I know that nowhere is earthquake proof. Are frequent tremors/quakes something I'd really have to get used to in Anchorage though?

In a word: Yes. Frequent tremors/quakes are something you would really have to get use to in Anchorage, or anywhere else in south central Alaska. Your source is correct, Alaska is the most seismically active place in North America.

The vast majority of our quakes (as many as 1,000 per month) are under a magnitude 4.0, which are not going to be felt unless you are standing almost on top of them. We average one quake greater than 4.0 per week, and a 5.0 quake once per month, statewide. Quakes that are 6.0 or greater are much less frequent.

In the last 55 years, there have been four very large quakes in Alaska:

• 03/28/1964 = 9.2
• 02/04/1965 = 8.7
• 03/09/1957 = 8.6
• 11/03/2002 = 7.9

It is only when the quakes get to be a magnitude 5.0 or larger, and within 100 miles, that they become a concern. Quakes below 5.0 rarely cause damage. The vast majority of our quakes are concentrated around the 130+ volcanoes and volcanic fields in Alaska. Which you will find along the Aluetian Island chain, along the Alaskan Range, and south central Alaska. Quakes in the Alaskan panhandle (southeastern Alaska) and north of the Alaskan Range are much less frequent.

Other Sources:
AEIC -- Alaska Earthquake Information Center
Alaska Volcano Observatory
West Coast and Alaska Tsunami Information

[Dakster]

Originally Posted by gobrien

The quakes usually just feel like somebody bumped the couch, although if you get a job in a multi-storied building built on rollers, you will feel the earthquake more.

Multi-storied building on rollers -- that would be an interesting, if not, scary, experience.

[roadfamily6now]

since living in Alaska (from the Aleutians to the Interior and now Anchorage) we have felt a lot of earthquakes. For the most part, I find them thrilling.
There was a good in about 10 years ago that we felt while living in Delta Junction. I was in the local grocery store and watched the floor ripple like ocean waves!

[gobrien]

Originally Posted by roadfamily6now

since living in Alaska (from the Aleutians to the Interior and now Anchorage) we have felt a lot of earthquakes. For the most part, I find them thrilling.
There was a good in about 10 years ago that we felt while living in Delta Junction. I was in the local grocery store and watched the floor ripple like ocean waves!

Did they have to repair the floor? That must have been pretty cool. The only seismic activity that I have felt here was due to military bombing excercises.

[roadfamily6now]

Originally Posted by gobrien

Did they have to repair the floor? That must have been pretty cool. The only seismic activity that I have felt here was due to military bombing excercises.

You know the only damage was some stuff that fell of the shelves. It was a nice "rolling" earthquake as opposed to those shaking ones.

[roadfamily6now]

Originally Posted by Dakster

Multi-storied building on rollers -- that would be an interesting, if not, scary, experience.

most of the barracks on Adak were built on rollers. Good thing too since Adak gets tons of quakes. I never found it to be scary but I do think that you feel the earthquakes a lot more in a building like that then a conventional building. Everything just sorta sways back and forth.