Premium
An indigenous origin for the South Pole Aitken basin thorium anomaly
Author(s) -
GarrickBethell Ian,
Zuber Maria T.
Publication year - 2005
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 - 10.1029/2005gl023142
Subject(s) - ejecta , thorium , geology , anomaly (physics) , structural basin , impact crater , geochemistry , physics , paleontology , astrobiology , astronomy , uranium , supernova , nuclear physics , condensed matter physics
The northwest portion of the Moon's South Pole‐Aitken basin contains an anomalously high abundance of thorium as determined by Apollo and Lunar Prospector gamma‐ray spectroscopy. The anomaly's proximity to the antipode of the Imbrium basin has led several investigators to suggest that the anomaly is the result of convergence of thorium‐enriched ejecta from the Imbrium impact. Examination of this complex region with new higher‐resolution thorium data and several other datasets reveals that a convergence of ejecta cannot explain the anomaly. Alternatively, we propose an indigenous and likely ancient source.