MOHO DEPTHS VERSUS GRAVITY ANOMALIES

Abstract

Isostatic gravity anomalies are the best suited anomalies for different geodetic applications, such as the interpolation and the geoid determination. Different isostatic hypothesis are discussed and used to compute the depths of the Mohorovic˘ié discontinuity (Moho depths). Isostatic anomalies are then computed using different isostatic hypothesis. Comparison among the different kinds of the gravity anomalies and their empirical covariance functions are made. Vening Meinesz isostatic model gives, more or less, realistic Moho depths. Both Airy-Heiskanen and Vening Meinesz isostatic models give nearly the same isostatic anomalies. Computing the Vening Meinesz Moho depths, and hence the Vening Meinesz isostatic anomalies, is a time-consuming task. Therefore, if the isostatic anomalies are the main goal of the computation, one may easily use the better known Airy-Heiskanen isostatic model.