Mafic minerals in the South Pole‐Aitken basin

1Xunyu Zhang,2Meng‐Hua Zhu,1Roberto Bugiolacchi
Journal of Geophysical Research, Planets (in Press) Link to Article [https://doi.org/10.1029/2018JE005870]
1Space Science Institute, Macau University of Science and Technology, Macau, China
2Chinese Academy of Sciences Center for Excellence in Comparative Planetology, Hefei, China
Published by arrangement with John Wiley & Sons

The formation of the South Pole‐Aitken (SPA) basin is thought to excavate the deep crust or mantle because of its large size. The pervasive orthopyroxene‐dominated materials found across the basin suggest that they either represent the SPA impact melt or the excavated materials from the lower crust and/or upper mantle. This study analyzes the relative content and distribution of mafic minerals in the SPA area based on the spectra from small fresh craters. The orthopyroxene‐dominated materials in the non‐mare regions are classified into two types based on their distribution and different composition. One is distributed from the center to the edge across the SPA basin and interpreted as the SPA impact melt. The other is Mg‐richer and generally located in some plagioclase‐rich regions (e.g., some large impact craters/basins and the SPA edge), thought to represent materials from the lower crust and/or upper mantle. For the maria in the SPA area, the basaltic materials in the northwest are found to be richer in olivine and/or clinopyroxene than the southern ones.

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