posted on Aug, 18 2023 @ 11:20 AM
Well so for the first time I bore witness to a swarm at Flegrei, which has been happening over the last few days. It has come in rapid bursts, but
each burst has been short-lived. Mags mostly in the 1-2 region, although a couple might have hit 3.
One thing to note is that IGNV is rating these quakes in Md, or Duration Magnitude. This is simply a measure of the entire time duration of the
earthquake signal, and is often used as a preliminary measurement at volcanoes until further reviews can be done on the data. I have heard that it is
relatively accurate up to about 3.0 magnitude.
I would characterize this seismicity as virtually identical to what we see at Yellowstone sometimes, when YS has short lived swarms, like around the
lake or like the small swarms around little west thumb. What I have seen so far in no way compares to the intense swarms of 1985/Maple Creek(2017)/YS
lake(2008)/Madison Plateau(2010) at YS. Not even close.
In addition, I have seen no other dangerous signatures such as tremor/long period events/tornillos, etc.
There is a curious low frequency (1-3 Hz) present however, on most stations that appears to correspond to tidal movements. It comes and goes
regularly. At first i thought it was background tremor, but over the last month or so it has become clear that this is normal. Otherwise people would
be running for the hills. It is all part of getting used to the baseline at Flegrei. So if something abnormal appears, I can report it immediately.
(Let's hope I never have to).
edit on Fri Aug 18th 2023 by TrueAmerican because: (no reason given)