Saturday, January 21, 2006

Alaska is a little different

My wife Ruth is in the living room watching “Dante’s Peak”, an action adventure movie staring Pierce Brosnan and Linda Hamilton, about a small town threatened by a large volcano. How can such talented actors be in such crapola? Boring!!! I’ll wait until she falls asleep on the couch and then I’ll change the channel.

Our Augustine Volcano has been on the quiet side. Seismicity remains low, but above background levels is all the reports are. There are 129 major volcanic areas in Alaska. About 1/3 are historically active, 1/3 have been active in the past 10,000 years, the rest are dormant. Seismic activity is monitored in real time at 30 volcanoes in Alaska by the Alaska Volcano Observatory. Satellite images of all Alaskan volcanoes are analyzed daily for evidence of ash plumes and elevated surface temperatures. Some volcanoes may currently display anomalous behavior but are not considered to be at a dangerous level of unrest. That’s information you don’t find in all of the other states.

A couple of months back my sister called me all excited. They just reported an earthquake in the Maryland and DC area. It registered 1.5 on the scale. I laughed. I asked her how many we had in Alaska that day. She said how many? I said 157. That might have been a high estimate. Guess how many earthquakes Alaska has regularly.
Daily = 50-100, Weekly = 400-700, Monthly = 1500-3000, Yearly = ~24000

This accounts for approximately 11% of the world's earthquakes and 52% of all earthquakes in the U.S. Alaska has more seismicity than any other region in North America and is by far the most seismically active state in the U.S.

The largest earthquake recorded in Alaska was a M9.2 that occurred on March 27, 1964 in the Prince William Sound. This was the 2nd largest earthquake ever recorded in world history. The energy released in this earthquake was equivalent to approximately 4 trillion pounds of explosive. The motions on the fault lasted for 4 minutes, rupturing an area about 800 kilometers long and 250 kilometers wide. The average movement on the fault was about 9 meters.

Info borrowed from the Alaska Earthquake Information Center.

If you can’t tell, things are a little slow at the clinic right now. But that’s a good thing.

4 comments:

pohanginapete said...

Hey Dave, Aotearoa/New Zealand is on the Pacific Rim of Fire; consequently, we get our fair share of earthquakes. Nothing like 157 a day, though... Actually, we had one this morning at 5:52 a.m.: 4.4 on the Richter scale. Naturally, at that hour I was still in bed; I felt the 'quake as a distinct jolt, or "push".

Dave said...

Thanks for posting. Alaska is over 656,000 square miles. I don't feel most of the earthquakes because they are out of our area. We do get our fair share in Anchorage though. New Zealand, that's a place I'd like to visit.

Cindy said...

I had absolutely no idea how much volcanic activity takes place in Alaska- I remember a few scary quakes (we lived almost right on the S.Andreas fault in CA) but no matter where you go, nature has something to say about things.
I had to chuckle when you said 'I'll wait for her to go to sleep and change the channel".. LOL, sounds too familiar ;)

Dave said...

I prefer volcano's and earthquakes to hurricances or tornado's.

You married to my evil twin? ;}