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

• Published in: Geophysical Research Letters
• Main Authors: Besserer, Jonathan, Nimmo, Francis, Wieczorek, Mark, Weber, Renee, Kiefer, Walter, Mcgovern, Patrick, Andrews-Hanna, Jeffrey, Smith, David, Zuber, Maria
• Other Authors: Department of Earth and Planetary Sciences Santa Cruz, University of California Santa Cruz (UC Santa Cruz), University of California (UC)-University of California (UC), Institut de Physique du Globe de Paris (IPGP (UMR_7154)), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), NASA Marshall Space Flight Center (MSFC), Lunar and Planetary Institute Houston (LPI), Department of Earth, Atmospheric and Planetary Sciences MIT, Cambridge (EAPS), Massachusetts Institute of Technology (MIT)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2014
• Subjects: [SDU.STU.PL]Sciences of the Universe [physics]/Earth Sciences/Planetology; Aitken; South Pole; South pole
• Online Access: https://hal.science/hal-02458599; https://hal.science/hal-02458599/document; https://hal.science/hal-02458599/file/Besserer%20et%20al.%202014.pdf; https://doi.org/10.1002/2014GL060240

International audience We 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 SPA impact likely played a major role in sculpting the lunar crust.