Efficient gravity data inversion for 3D topography of a contact surface with application to the Hellenic subduction zone

We develop the theoretical foundations, numerical algorithms and computer programs to retrieve the 3D geometry of a density interface from gridded gravity data. The solution depends on constraining assumptions on permissible density values. An integral equation is solved by a new method of local corrections to find the density interface. The method is efficient and does not require trial-and-error forward modeling. We also discuss a method, based on upward and downward continuation, to isolate gravity effects from selected depth ranges. Both new methods are applied to create a model of the Moho surface for the Hellenic subduction zone. The resulting model is discussed relative to available seismic data and previous gravity analysis.