Terrain correction for gravity measurements, using a digital terrain model (DTM)

Abstract

A single-term expression is given to calculate the gravitational effect for any square vertical prism with a sloping surface. A moderate measure of approximation is involved. The expression is well suited to automatic calculation of the terrain correction when a digital terrain model is available. The subjective or intuitive averaging of the elevation of a large sector is thereby diminished. For the square area immediately surrounding the gravity station, three geometrical models are presented, of which the one may be selected which best suits the local morphology as well as the desired accuracy.