Regolith in the South Pole-Aitken Basin is Mainly Indigenous MaterialThis abstract is concerned with the probability that a mission to a site within the South Pole-Aitken basin (SPA) would yield a meaningful sample of typical SPA floor material. The probability seems favorable, barring a highly atypical landing site, because the chemical composition of the SPA interior, as determined remotely from orbit, is different from that of the surrounding lunar surface. How representative would the sample be? To what extent have lateral transport or later events compromised the original chemical and mineralogical composition of the floor material? Where or in what kind of deposit should the mission land to provide the best example? We address these questions from the point of view of modeling of impact ejecta deposits. SPA is the largest lunar impact basin. Shallow for its diameter, it has a subdued gravity signature, a lower albedo, and a more Th- and Ferich interior than the surrounding highlands (the Feldspathic Highlands Terrane, FHT). Its floor may represent noritic or perhaps (but less abundant) gabbroic lower crust of the FHT, the upper crust stripped away by the basin-forming impact, possibly an oblique one.
Document ID
20030111139
Acquisition Source
Headquarters
Document Type
Conference Paper
Authors
Haskin, L. A. (Washington Univ. Saint Louis, MO, United States)
Gillis, J. J. (Washington Univ. Saint Louis, MO, United States)
Jolliff, B. L. (Washington Univ. Saint Louis, MO, United States)
Korotev, R. L. (Washington Univ. Saint Louis, MO, United States)