It's been nearly a month since the September 25 magnitude 2.9 earthquake that, at least for now, stands as the last event in the Noatak swarm. For Noatak residents, this must be a welcome change from the 460 earthquakes - many of them felt - that were recorded from April through July.

The Noatak swarm has been one of the more interesting sequences in an unusually busy earthquake year in Alaska. It began on the morning of April 18 with a pair of magnitude 5.7 earthquakes 12 minutes apart, felt strongly in Noatak and at the Red Dog Mine and as far away as Nome. A third M5.7 occurred on May 3, followed by a M5.8 on June 7 and another M5.7 on June 16:

Each of these earthquakes was followed by a vigerous aftershock sequence, including about 20 events with magnitudes of 4 or greater. Altogether, we located more than 500 aftershocks before the swarm appeared to wind down in September. You can read about our response to the swarm in the News-Miner here:

http://www.newsminer.com/features/sundays/alaska_science_forum/seismologists-answer-the-call-to-rural-alaska/article_1ff4ceb2-dd5c-11e3-8efc-0017a43b2370.html

Our summary of the swarm, including information about the tectonic setting and source mechanism, is on our Significant Events page (here).