Generalized Compensation Model for the Gravimetric Moho Recovery

Abstract

A constant value of the Moho density contrast is often assumed in methods for a gravimetric determination of the Moho geometry. This assumption might be sufficient in some regional studies. In global studies, however, this assumption is not reasonable due to the fact that the Moho density contrast vary significantly. Large errors then can be expected in the Moho geometry determined globally from gravity data. In this study we utilize a generalized compensation scheme based on variable depth and density of compensation. The Moho depths are determined based on assuming the variable Moho density contrast. We demonstrate that this assumption (instead of a uniform model) significantly improves the agreement between the global gravimetric and seismic Moho models; the RMS fit of the gravimetric result with the CRUST1.0 seismic Moho model is 4.5 km (for a uniform model) and 3.0 km (for a variable model).