Okay, I might have figured out how to post to my own blog here. Let’s just have a go at it.
I’m starting this blog because it’s so terribly hard to find anyone at all to talk to about volcanoes, and lately I see one of my favorite volcanoes doing something very interesting. That would be Mt. Vesuvius in Italy, and since a moderate and shallow earthquake to the north of there last week I’ve been seeing some elevated and quite interesting seismic activity at the BKE V seismograph situated on the east flank of the volcano.
Now I’ve been watching that volcano for quite a while, and I’ve never yet seen anything like the seismic activity I’m seeing there now. It’s fascinating at best, and very worrisome at worst. The volcano isn’t smoking or rumbling perceptibly as yet, but anyone watching the seismographs there has to be sitting up in their chair and paying close attention.
Above is what I started seeing yesterday, and it’s what is termed a long period event, seen here in red. It is a sign of a pressurizing volcano. The fact that this followed a shallow earthquake not far north of the volcano is good reason for concern given what has been showing up on the webicorder at that station since:
So here we go folks. This is not rockfall going on, this is seismic activity. Now it might just quiet down and go away, but since it immediately followed a shallow earthquake just north of the volcano, and since there’s an extensive magmatic system in the area it stands to reason that this recent quake has somewhat stirred the pot there at Vesuvius.
I’m guessing that what we are seeing here are pressure waves reverberating around the magma chamber there, and exerting quite a bit of pressure on the surrounding rock, breaking it in places as it does so, and providing for magma intrusion into that rock. This is especially interesting when one considers that only the BKE V seismometer is recording this seismic activity, on the east flank of the volcano. We do not see the same activity on more distant recorders, and the activity continues:
So I have been watching this go on, far more seismic activity than I’ve ever seen at Vesuvius, and I wrote Michael Rampino about it. I’ve not heard back from him, but if anyone would know what’s going on there I figure it would be him. I sure hope Vesuvius is not working up to an eruption as that would really mess up a lot of folks’ day there.