Estimating Thorium Abundances of Basalt Ponds in South Pole Aitken Basin: Implications for the Composition of the Farside Lunar Mantle
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چکیده
1761. Figure 1. CSR FeO map of the central basalt pond in Apollo crater. The edges of the basalt pond were modeled as different units due to lateral mixing with the surrounding materials. The absolute FeO abundances from CSR may be overestimated by as much as 2 wt.% [15]. Figure 2. Map of modeled Th compositions used in the forward model. Region 1 = 0.9 ppm Th, Region 2 = 2.5 ppm Th, and Region 11 = 10 ppm Th (this value is overestimated by a factor of 2 to account for the small size of region 11). Figure 3. Map of LP-GRS Th data. The basalt pond is outlined in
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