It’s been an interesting 12 hours: seismic activity in Interior Alaska has really ramped up, causing a multitude of small quakes, and three large enough that we felt and heard them. Last night there was a magnitude 3.5 earthquake around 9 miles from our house, and this morning there have been two more (a 3.2 about 11 miles away and a 2.9 that was only 6 miles away). None caused any damage, but they do shake the house and make enough noise that the dogs perk up. Experiencing tectonic forces so large and powerful is a sobering (and exciting) experience.
There’s a general perception in the lower 48 that California is the most seismically active place around, but the huge subduction zone that stretches from the Aleutian Islands all the way to the west coast of North America causes earthquakes and volcanic activity all over Alaska. The 1964 Good Friday quake (pictured in the photo) was the largest ever recorded in North America, and the 2002 Denali earthquake (which we rode through at the Bird Observatory) was an order of magnitude larger than the 1989 Loma Prieta earthquake that ripped up the Bay Area during the World Series. Most of the major earthquakes are south of the Alaska Range where the plates are moving against each other closer to the surface, but all the pressure creates fault lines up here in Fairbanks and can trigger some fairly large events.
Our house is less than ten years old, but knowing it went through the Denali quake without incident allows us the luxury of appreciating the power of the geologic processes at work without worrying they’ll destroy our house.
Update: 31-May-2009, 21:35. Magnitude 3.8, eight miles away.