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Compositional implications regarding the lunar origin of the ALHA81005 Meteorite
Author(s) -
Kallemeyn Gregory W.,
Warren Paul H.
Publication year - 1983
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/gl010i009p00833
Subject(s) - regolith , geology , meteorite , geology of the moon , geochemistry , breccia , lunar soil , astrobiology , mineralogy , basalt , physics
Geochemically, ALHA81005 has all the attributes expected of a regolith sample from the lunar highlands. Most important is its Fe/Mn ratio (77), within uncertainty the same as the mean lunar ratio. There are significant differences, however, in comparison to previously sampled lunar regoliths. The closest precedents are the Apollo‐16 and Luna‐20 regoliths, particularly the latter, but ALHA81005 has lower contents of Na, Ti, and incompatible elements. Feldspathic granulitic breccias such as 72559, which texturally resemble the most abundant type of clast in ALHA81005, are also similar compositionally. From its low KREEP and Na contents we infer ALHA81005 originated well away from the K, Th, and U‐rich region near the center of the nearside, at least as far away as the eastern limb.