reply to post by Olivine
Some volcanoes have rested 100 million years between major eruptions. I was just watching a documentary about that. They know this because of ash
layers in the geologic record. Point is, any one of the major calderas could reactivate at any time, and it was proven not long ago that rising magma
under pressure can melt upper crust layers much faster than previously thought.
And it makes sense really, seeing as a huge magma body will have such intense heat that if additional intrusion occurs from way deep down near the
mantle, undetected, it could burn its way through now solid rock to the surface within months. The planet could be in real trouble if another
continental flood basalt (CFB) ever decided to rear its ugly head again. Or if a new one formed, like potentially out there in the south Pacific.
They are hiding the full coordinates. I'm sure of it. What scientist, seeking absolute accuracy, would settle for 4 decimal places? Not a chance. And
after clicking around various networks at the IRIS MDA link I gave, nope, they are all 2 decimal places. So stick to using Quackery for metadata on
stations, and you can at least get within 35 feet or so.
It does make me question the accuracy of programs like GEE, and it may be another reason why it takes stepping up to some pretty serious stuff before
you can do epicenter locating. I still can't do it, even after begging for them to include it. They don't want amateurs having that capability, and
that much has become clear- not from speculation- but from talking with my contacts. Otherwise, IRIS would provide exacting coordinates down to SIX
decimal places or better.
As to an asphalt volcano possibly emerging at the LA sinkhole, the elements of methane and oil are there, and they are found near salt domes,
according to what I read. I think they were first discovered around 2002, and there are some off the coast of California as well. So there is a slight
But it would be a total trip if an ancient volcano buried deep under there started reactivating. Highly improbable, but possible. I've been studying
the particulars of eruptive sequences, and an interesting thing occurred at one of them where magma rose, but then it stopped being blocked for a bit.
And that in turn caused gas emissions to stop as well. 3 days later, kapow. Sure makes me wonder about a situation like Yellowstone or Toba, and what
kind of pressure could be building when the gas emissions stop or become greatly reduced. It could be due to blockages that are getting ready to go
boom. So yeah, seismicity is still probably the most important element to monitor.
Anyways, I digress and went off on a tangent. Now we're back to daytime and I see the low frequency has returned at the sinkhole, on all stations.
But not paying it any more attention. Pretty sure it is cultural noise. Either that, or we are having a real bad case of these tremor type signatures
appearing coincident with daylight hours and machinery working the site, and being mistaken for cultural noise. Chances are low of that. I'm sticking
with noise until I see something that obviously rises above it. So yeah, all you's watching the helicorders, if it isn't short and spiky, forget it.
Or dwell on noise. Your choice.