[S03-5] Imaging of heterogeneities in the Earth with seismic scattered waves and ambient noise V

[S03-5-03] Monitoring volcanic and geothermal fields using seismic noise: the case study of the Las Tres Virgenes geothermal field (Mexico)

^○Marco Calo, Erik Alberto Lopez Mazariegos, Valente Ramos Avila, Javier Francisco Lermo Samaniego (National Autonomus University of Mexico (UNAM))

Volcanoes are known to be dynamic systems where physical properties change over the time because of the magma ascending into de main and secondary conduits that produce variations of stress on the edifice and in the crust. Geothermal systems under exploitations are often compared to volcanoes because re-injection of fluids in depth through wells may create small perturbations of the field that can also generate induced seismicity.
In the last decade the analysis of large records of seismic noise allowed to retrieve useful information about the non-stationary condition of the physical properties of volcanoes with the aim to develop efficient forecasting eruption models. First attempts to detect seismic velocity variations during injections also showed that the seismic noise monitoring might be use to observe and describe such variations over the time.
In this work we show how the seismic noise correlation technique can be applied to monitor changes on seismic velocities into a geothermal field operating in a volcanic region, and which are the observables originated by the power plant activities and those related to the natural activity of the area.