Chen, Jian and Ling, Zongcheng and Jolliff, Bradley L. and Sun, Lingzhi and Qiao, Le and Liu, Jianzhong and Fu, Xiaohui and Zhang, Jiang and Li, Bo and Liu, Changqing and Qi, Xiaobin and Lu, Xuejin and He, Zhiping and Xu, Rui (2022) Radiative Transfer Modeling of Chang’e-4 Spectroscopic Observations and Interpretation of the South Pole-Aitken Compositional Anomaly. The Astrophysical Journal Letters, 931 (2). L24. ISSN 2041-8205
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Abstract
Chang'e-4 landed in the Von Kármán basaltic zone affected by Finsen ejecta from the South Pole-Aitken (SPA) "compositional anomaly" (SPACA), providing an opportunity to untangle the origin of the SPACA. We developed a mineral abundance unmixing model and built a spectral library composed of mineral mixtures of plagioclase, low-Ca pyroxene, high-Ca pyroxene, and olivine. Based on the mineral abundances returned by our model, the average plagioclase abundance (60.4 vol.%) of SPACA is beyond the high-plagioclase end of the mineralogical range of SPA impact melt differentiation products and would require an additional contribution from crustal materials. We suggest that either the crust was not entirely removed in the SPA-forming impact or the ejecta from post-SPA basins fed feldspathic materials back onto the SPA basin floor. Our unmixing analyses indicate that the surface regolith of the SPACA is a mixture of 70.2% crustal materials and 29.8% Fe- and incompatible-element-enriched materials.
Item Type: | Article |
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Subjects: | AP Academic Press > Physics and Astronomy |
Depositing User: | Unnamed user with email support@apacademicpress.com |
Date Deposited: | 27 Apr 2023 06:06 |
Last Modified: | 21 Sep 2024 03:53 |
URI: | http://info.openarchivespress.com/id/eprint/1080 |