An Approach to Moho Topography Recovery Using the On-Orbit GOCE Gravity Gradients and Its Applications in Tibet

Abstract

It is significant to determine the refined Moho topography for understanding the tectonic structure of the crust and upper mantle. A novel method to invert the Moho topography from the on-orbit gravity gradients is proposed in the present study. The Moho topography of Tibet is estimated by our method, which is verified by previous studies. The research results show that: (1) the deepest Moho of Tibet, approximately 70 km, is located at the western Kunlun area, where it corresponds well to that of previous publications; (2) clear Moho folds can be observed from the inverted Moho topography, whose direction presents a clockwise pattern and is in good agreement with that of Global Positioning System; (3) compared with the CRUST 1.0, our inverted Moho model has a better spatial resolution and reveals more details for tectonic structure; (4) the poor density model of the crust in Tibet may be the main reason for the differences between the obtained gravity Moho model and seismic Moho model; (5) by comparing our inverted Moho with those from previous publications, our method is correct and effective. This work provides a new method for the study of Moho topography and the interior structure of the Earth.