Silicon Variation on the Moon as Observed by the Kaguya Gamma-Ray Spectrometer and Chandrayaan-1 Moon Mineralogy Mapper (M³) Calibration,тезисы доклада
Место издания:NASA Ames Research Center Moffett Field, CA
Аннотация:This presentation demonstrates an investigation analysis of the Si distribution based on the 4934 keV Si gamma ray peak. On global scales, our results are the first to detect indicate Si concentrations at global scale similar to those discovered in lunar samples consistent with those measured for lunar samples. We processed Kaguya GRS data using the gamma ray data analysis program using a grid of 10 degrees in longitude and latitudeto construct a map of 10 degrees resolution in longitude and latitude. Firstly, a Si peak analysis was accomplished by the Aquarius program software and then, a correction of the GRS data were corrected for altitude and thermal neutron density was performed. Finally, followed by a normalization process was performed using archived laboratory-based Si data of Apollo returned samples returned by the Apollo program.
According to our Si map, the range of Si abundances on the Moon ranges from between about 17 to 28 wt%. Further investigation is needed to determine whether locally small-scale high Si abundances of around 30 wt% are due real or correspond to calibration artifacts. Highland terrains have a higher Si content (24–28 wt%) when compared to mare regions (17-21 wt%) consisting of mafic rocks and intermediate surface types (20–24 wt%). The constructed Si map obtained by combined analysis of Kaguya GRS and M³ data will provide an important aspect information for both an understanding of the mineralogical distribution of minerals across the lunar surface and its evolution of the lunar surface since its formation.