Slip inversions in complex media: the uncertainty of rupture parameters estimation due to lateral velocity heterogeneities and topography

Earthquake slip inversions aiming to retrieve rupture characteristics typically assume 1D velocity models and a flat Earth surface. However, the heterogeneous nature of the crust and the presence of rough topography lead to seismic scattering and other wave propagation phenomena, thus introducing complex 3D effects on ground motions. In this study we investigate how realistic velocity perturbations and topography affect source imaging results. In particular, we quantify the effects of these two factors on both kinematic and dynamic source inversion parameters depending on the maximum frequency considered. We first consider a synthetic case, where several station configurations around the causative fault are explored. We then extend our investigation to the 2009 Mw 6.1 L'Aquila earthquake. Our study can help in understanding the robustness of practical slip inversion results