[kstewskis]

Isn't there volcanic activity in that area?

I seem to remember wondering in the 80's if Mammoth would ever blow up.

[Strategerist]

Isn't there volcanic activity in that area?

This swarm isn't anwhere near the Mammoth Lakes caldera really; several years ago the Caldera itself had dozens of swarms more intense than this swarm.

Also quake swarms can happen due to purely tectonic (non-volcanic) causes.

Calderas can easily go thousands of years with quake swarms, inflating/deflating, and no eruption.

[Mike Darancette]

I seem to remember wondering in the 80's if Mammoth would ever blow up.

This is not in the Caldera but near the Mono Craters an area of very recent activity.