Resolution Test for Moment Tensor Inversions with Varying Seismic Network Configurations

Active volcanoes are often covered with a sparse seismic network. In the case of a volcanic crisis, this number can even be more reduced due to noise saturated data at certain stations, electrical failures, or stations being destroyed by the volcanic material. Numerical tests using synthetic waveforms are performed to examine how well different source mechanisms (isotropic, double-couple, CLVD) with varying orientations and at different depths can be resolved using moment tensor inversion. As a case study we use the seismic network configuration at Soufrière Hills volcano, Montserrat. We model the ground displacements using several source time functions: a Küpper wavelet, a Ricker wavelet, and a step function, each relating to a different source process. The number of stations included in the moment tensor inversion is varied mimicking an eruption scenario.