Iterative 3D gravity inversion with integration of seismologic data

Depending on the a priori knowledge, different methods can be chosen for gravity inversion. The method we propose is suitable for cases in which little is known about the crustal structure, except the presence of a sharp density contrast, as occurs at the Moho or at the base of a sedimentary basin. The method combines the downward continuation with the direct evaluation of the gravity field of the undulations of the boundary surface in an iterative process. The a priori assumption of the reference depth of the boundary and density across the surface is necessary. If the depth of the boundary is known along a profile or in single points from seismologic (or other) investigations, this piece of information is used to anchor the boundary. In lack of such knowledge general geophysical considerations must be used to obtain an estimate of the boundary in the undisturbed state. The method is tested in a 3D synthetic model situation, evaluating the effect of erroneous a priori assumptions and noise.