Hood's South Side Shake-Up

Mt. Hood had a smallish earthquake swarm today, but one quite a bit larger than has been seen for several years, with 14 located events over about an hour. It looks rather nice on the seismogram, even though you probably wouldn't even feel the largest of these quakes if you were standing right on top of it. A quick look at the epicenter plot shows that the quakes are clearly aligned along a plane, which means this is probably not related to any volcanic process. Rather, they are more likely related to (or effectively aftershocks of) this magnitude 4.5 quake 4 years ago.

Not to be outdone, Mt. St. Helens responded with this a few hours later.