Jane,

If a magma chamber volcanically vents, could there not be a generalized lithospheric reaction under gravity? Seems like there would be, but my question is really if such a reaction could happen rapidly and create a tsunami. A couple of months ago there was a 5.2 quake south of Louisiana, and I think that may have been due to oil extraction. I never did see a tensor solution on that.
Seems to me that the beach ball would be all white because all the first motions would be down, meaning all the motions would be dilatational from the recording stations. I think it would register as an implosion. I'll have to ask J. Vidale or Don about this. So my question is if this is possible in the Aleutians due to vulcanism.

Glen