Full Moment Tensor Retrieval from Waveform Inversion in the Larderello Geothermal Area

The area is characterized by numerous events with small magnitude; the duration magnitude, Md, of the events which occurred from 1977 to 1994 varies from 0.5 to 3.5. The algorithm developed by SILENY and PANZA (1991) and SILENY et al. (1992) allows us to retrieve the full source moment tensor from waveform inversion. The factorization of the moment tensor rate functions into a source mechanism and a source time function, and the further decomposition into a double-couple, a compensated linear vector dipole and a volumetric component, allows us to determine if there are phenomena in the source that can be related to the circulation of fluids, a quite common event in geothermal areas.