GRAIL gravity constraints on the vertical and lateral density structure of the lunar crust

Abstract

AbstractWe analyzed data from the Gravity Recovery and Interior Laboratory (GRAIL) mission using a localized admittance approach to map out spatial variations in the vertical density structure of the lunar crust. Mare regions are characterized by a distinct decrease in density with depth, while the farside is characterized by an increase in density with depth at an average gradient of ∼35 kg m−3 km−1 and typical surface porosities of at least 20%. The Apollo 12 and 14 landing site region has a similar density structure to the farside, permitting a comparison with seismic velocity profiles. The interior of the South Pole‐Aitken (SP‐A) impact basin appears distinct with a near‐surface low‐density (porous) layer 2–3 times thinner than the rest of the farside. This result suggests that redistribution of material during the large SP‐A impact likely played a major role in sculpting the lunar crust.