On the origin of mascons and moonquakes

Abstract

The discovery of positive gravity anomalies over the circular maria by Muller and Sjogren (1968) has been one of the most discussed results of the Apollo lunar exploration program. That the contours of the gravitational equipotential surface strongly correlate with the circular maria suggests that these anomalies originated in the processes that created and filled these maria and that they have since been supported by the finite strength of the lithosphere. Two main groups of hypotheses, involving essentially external and internal processes, have been put forward to explain these departures from the expected isostatic model.