Density Structure of the Von Kármán Crater in the Northwestern South Pole-Aitken Basin: Initial Subsurface Interpretation of the Chang’E-4 Landing Site Region

• Published in: Sensors
• Main Authors: Chisenga, Chikondi, Yan, Jianguo, Zhao, Jiannan, Deng, Qingyun, Barriot, Jean-Pierre
• Other Authors: Wuhan University China, Malawi University of Science and Technology, China University of Geosciences Wuhan (CUG), Géopôle du Pacifique Sud (GePaSUD), Université de la Polynésie Française (UPF)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2019
• Subjects: Von Kármán Crater; density structure; gravity inversion; Chang'E-4 mission; [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]; Aitken; South Pole; The Landing; South pole
• Online Access: https://hal.science/hal-03155669; https://hal.science/hal-03155669/document; https://hal.science/hal-03155669/file/JP%20Barriot,%20Density%20Structure%20of%20the%20Von%20K%C3%A1rm%C3%A1n%20CRATER.pdf; https://doi.org/10.3390/s19204445

International audience The Von Kármán Crater, within the South Pole-Aitken (SPA) Basin, is the landing site of China's Chang'E-4 mission. To complement the in situ exploration mission and provide initial subsurface interpretation, we applied a 3D density inversion using the Gravity Recovery and Interior Laboratory (GRAIL) gravity data. We constrain our inversion method using known geological and geophysical lunar parameters to reduce the non-uniqueness associated with gravity inversion. The 3D density models reveal vertical and lateral density variations, 2600-3200 kg/m 3 , assigned to the changing porosity beneath the Von Kármán Crater. We also identify two mass excess anomalies in the crust with a steep density contrast of 150 kg/m 3 , which were suggested to have been caused by multiple impact cratering. The anomalies from recovered near surface density models, together with the gravity derivative maps extending to the lower crust, are consistent with surface geological manifestation of excavated mantle materials from remote sensing studies. Therefore, we suggest that the density distribution of the Von Kármán Crater indicates multiple episodes of impact cratering that resulted in formation and destruction of ancient craters, with crustal reworking and excavation of mantle materials.