Iterative migration of gravity and gravity gradiometry data

Abstract

The geological interpretation of gravity and gravity gradiometry data is a very challenging problem. 3D inversion represents the only practical tool for the quantitative interpretation of gravity gradiometry data. However, 3D inversion is a complicated and time-consuming procedure that is very dependent on the a priori model and constraints used. 3D migration gives a rapid imaging of a geological target that can be used for interpretation or as an a priori model for subsequent 3D regularized inversion. This method is based on a direct integral transformation of the observed gravity gradients into a subsurface density distribution. Moreover, migration can be applied iteratively to get more accurate subsurface density distribution, and the results are comparable to those obtained from regularized inversion. We present a model study and a case study for the 3D iterative imaging of FTG gravity gradiometry data from Nordkapp Basin, Barents Sea.