Staggered grids as a tool to improve the model resolution in seismic tomography for elliptical anisotropic media

In this study we present the use of staggered grid as a tool to improve the resolution of inverse model in seismic tomography in the case of elliptical anisotropic media. We analyze two synthetic models, both showing elliptical anisotropic characteristics, with different complexity: the first consists of a body with rectangular shape having inside an anomaly with higher velocity and the second one is characterized by morphological variation to simulate a watershed. This second case is studied for both cross-hole and high ray coverage configuration. Successively, a previous field survey is analyzed introducing staggered grids and the results are compared with the old ones, solved using a constant cells’ size model. Staggered grid give enhanced results in terms of the velocity model and can be used as a tool to improve the knowledge of the studied domain by determining cells with variable shape and size, useful to infer a good initial model for a further inversion. This conclusion applies also to isotropic media.