[G02-P] Poster

[G02-P-12] Determination of Moho depth models for Greece using different gravity inversion methods

^○Vassilios Grigoriadis, Ilias Tziavos (GravLab, Department of Geodesy and Surveying, Aristotle University of Thessaloniki, Thessaloniki, Greece)

In this study, three of the most common methods of determining the Mohorovicic (Moho) discontinuity are employed towards the development of new Moho-models for the area of Greece by gravity inversion. The first method is conducted in the spectral domain and is based on an iterative approach following the Parker-Oldenburg formula and applying a low-pass filter for the stabilization of the finally produced solution. The background of the second method is in line with the well-known Bott's method combined with a Gauss-Newton formulation and a regularization technique focusing on a well-controlled solution. The entire procedure incorporates tesseroids in the modelling part and an adaptive iterative scheme for the optimal approximation of the finally determined Moho-depth surface. The solution of Vening-Meinesz and Moritz inverse isostatic problem is carried out by the third method along with non-isostatic corrections applied to the Moho-height differences estimated by the gravity data and the seismic constrained information incorporated in the inversion algorithm. The gravity data used in the computations of the three methods were derived from GOCO05s and EGM08 global geopotential models. The aforementioned methods are reviewed in terms of their computational efficiency as well as the assumptions and limitations required for their numerical evaluation. The Moho models derived by the three methods are inter-compared and compared also with a model derived for the test area by a previous study, which is based on high resolution local gravity databases. An external validation test of the new models was performed by comparing with Moho depths derived by seismic data in a number of stations in the area under consideration. Some remarks, conclusions and suggestions are finally drawn mainly related to the performance of each method and taking into account the strong features of the gravity field in the area under study.