Above, the lunar meteorite stones from Oman are grouped under 24 subheadings, a number that reflects the author’s working hypothesis for the number of meteorite falls represented. The number may be as high as 25 if Dhofar 489 is not paired with Dhofar 303 et al. (23 km separation; Table 4). The lower limit is more difficult to establish. It could be as low as 17 if (1) JaH 348 is terrestrially paired with Dhofar 1436/1443 (similar composition and texture, but 143 km separation; Table 4), (2) Shişr 160 is terrestrially paired with Dhofar 1428 (similar composition and texture, but 122 km separation; Table 4), (3) Dhofar 302 is paired with either Dhofar 081 et al. or Dhofar 303 et al. (proximity, Table 4), (4) Dhofar 025 and Dhofar 287 are paired (proximity), (5) Dhofar 1180 and 1428 are paired (proximity), (6) SaU 449 is terrestrially paired with Dhofar 925/960/961 (similar composition and petrography, but 340 km separation), and (7) Shişr 166 is paired with Dhofar 026 and its small pairs (similar composition, but 33 km separation).
Among the lunar meteorites from Oman, similarities in bulk composition suggest possible launch pairing (one impact on the Moon delivering more than one meteorite to Oman) for SaU 449 with Dhofar 925/960/961 (Korotev et al. 2009), JaH 348 with Dhofar 1436/1443, Shişr 160 with Dhofar 1428, and Shişr 166 with Dhofar 026/457–368. Compositional similarities can only suggest launch pairings and compositional differences provide only weak evidence against launch pairings, thus other launch pairings may exist. For example, to first order, Dhofar 025 et al., Dhofar 026 et al., Dhofar 490/1084, Dhofar 1428, Shişr 160, and Shişr 166 are all similar in composition (Figs. 4, 5, 7, and 29). They also overlap in composition, however, with Dar al Gani 262, NWA (Northwest Africa) 482, NWA 2200, NWA 6481, NWA 6578, Allan Hills 81005, Larkman Nunataks 06638, MacAlpine Hills 88015, Miller Range 090034, and Queen Alexandra Range 93069 (Fig. 20). The similarities are not necessarily because these meteorites are all paired or launch paired, they merely reflect that these meteorites are all typical of the feldspathic highlands and that their compositions reflect the typical composition of the surface of the lunar highlands, that is, 27–30% Al2O3, 4–5% FeO, 6–10 μg g−1 Sc, 0.7–1.7 μg g−1 Sm, and 0.2–0.6 μg g−1 Th (Korotev et al. 2006). Nevertheless, both texturally and compositionally, Dhofar 1428 is very similar to MacAlpine Hills 88105 (Fig. 31) and these two meteorites are good candidates for a two-continent launch pair.
Figure 31. Comparison of Dhofar 1428 to MAC 88105. Error bars represent 95% confidence limits on the concentration ratios based on the subsample data for Dhofar 1428 (N = 8, Table 1). (a) For major elements, the two meteorites are nearly identical except that Dhofar 1428 is 11% richer in MgO and Na2O. (b) Trace lithophile elements are also essentially identical, except for those elements (open circles) enriched in hot-desert meteorites from weathering processes. For elements not plotted (e.g., Mn, K, Ni, Ir), error bars are large. MAC 88105 data from Jolliff et al. (1991), Koeberl et al. (1991); Lindstrom et al. (1991), Palme et al. (1991), Warren and Kallemeyn (1991), and Joy et al. (2010).
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