The Amplitude Ratio plugin for MSNoise - Bringing SARA (Taisne et al 2011) to MSNoise
Seismic amplitude ratio analysis (SARA) has been used successfully to track the sub-surface migration of magma prior to an eruption at Piton de la Fournaise volcano, La Reunion. The methodology is based on the temporal analysis of the seismic amplitude ratio between different pairs of stations, along with a model of seismic wave attenuation. This method has already highlighted the complexity of magma migration in the shallower part of the volcanic edifice during a seismic crisis using continuous records. We will see that this method can also be applied to the localization of individual earthquakes triggered by monitoring systems, prior to human intervention such as phase picking.
- Follow the MSNoise installation instructions (here)
- Install
bottleneckusing either conda:conda install -c conda-forge bottleneckor pip:pip install bottleneck - Install MSNoise-SARA
In a new or current MSNoise project, once the station table has been populated and the archive scanned:
msnoise config set plugins=msnoise_sarais equivalent to going in the web Admin and setting thepluginsconfiguration bit. Note the underscore and not a dash.msnoise p sara installwill set up the MSNoise-SARA database tables and- automatically create the
SARA_ENVjobs if the database already containsCCjobs. - if your DB doesn't yet contain
CCjobs and you only wantSARA_ENVjobs, simply runmsnoise new_jobs --nocc
- automatically create the
msnoise p sara envelopewill compute the envelope of the signal for all available datamsnoise p sara ratiowill compute the ratio of the envelopes for each pair of stations (only for common data, of course)msnoise p sara plot ratioswill plot the ratios of all station pairs.