Forward and Inverse Modeling of the seismic and electromagnetic disturbances associated with localized seismic sources in volcanic areas
Abstract
We consider a seismic source characterized by a moment tensor in a water-saturated porous material with piece-wise constant seismic velocities corresponding to different geological units. We have developed a finite element code to compute the seismograms, the electrograms and the magnetograms associated with the source, the conversion of the mechanical energy to electromagnetic energy at the position of heterogeneities and the co-seismic signals traveling at the same speed than the seismic waves. In our model, the electromagnetic energy is generated through the electrokinetic coupling in porous materials. This coupling is related to the relative displacement between the pore water and the mineral grains coated by the electrical double layer. We show that in the case of a noisy environment, the electromagnetic information is complementary to the seismic information to recover the position of the source and to invert the moment tensor, which in turn provides information on the stress state of the volcano.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2011
- Bibcode:
- 2011AGUFM.V52B..01R
- Keywords:
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- 0450 BIOGEOSCIENCES / Hydrothermal systems;
- 7280 SEISMOLOGY / Volcano seismology