Citation:
Bell, A.F., La Femina, P.C., Ruiz, M. et al. Caldera resurgence during the 2018 eruption of Sierra Negra volcano, Galápagos Islands. Nat Commun12, 1397 (2021). https://doi.org/10.1038/s41467-021-21596-4
Relevance for SeisComP Users:
I used offline playbacks of minseed data from 10-15 stations on Sierra Negra Volcano in SeisComp3 to generate the seismicity catalog for this project. In particular I used scanloc for event detection and NonLinLoc for event relocation.
Can you tell more about the seismic processing? I can read you did the seismic data filtering and STA/LTA in Obspy, let scanloc aggregate triggers into origins and ended up relocating in NLL…
Can you briefly tell how you passed obspy triggers to scanloc?
Hi Fred, thanks for your comments. There were two approaches to seismic processing in this work, in the first approach, one of the authors made a catalog of events using a single station (VCH1, which has years worth of recorded data), on which the STA/LTA trigger was used to identify events on this station. There was also a simple procedure for estimating the magnitude of these events. This was a simple way to estimate the frequency and magnitude of earthquakes over a long time period (Jan 2018 -August 2018). This was done entirely outside of Seiscomp.
For the second approach, I took all available station data (from the temporary network that was deployed in 2018) and fed it into Seiscomp’s offline playbacks, used scanloc for the event detection, and then relocated using NLL. Hence I came up with a fully located catalog that covered the period April-August 2018. This was done entirely within Seiscomp. Hope that clears it up.
So the magnitude in papers are seiscomp’s or single station approach’s?
And how did you interfaced with hash? In particular, did you pick polarities in seiscomp? Going back an forth from one to another when adjusting FM results must have been quite time consuming for so much events… Did you find a shortcut?
The magnitudes in the paper are a mix of the Seiscomp catalog (shown as coloured circles in the paper, computed by SC3 using H+B attenuatation law for S. California) and magnitude estimates from a single station detection (coloured in blue in the paper, estimated as described in the Methods section). As far as I know, polarities were picked by someone else, done in Matlab, and I’m afraid I did not contribute to the FM studies.
