Petrography, geochronology and volatile inventory of lunar meteorite Northwest Africa 12593

The petrography and geochemistry of lunar meteorite Northwest Africa (NWA) 12593 reveals an association with the ferroan anorthosite and magnesian suites, as well as highlands-type clasts that are compositionally distinct from Apollo highlands material, re-affirming previous observations of increased compositional diversity in lunar crustal rocks outside of the Apollo sampled region. A large number of apatite grains were identified in lunar meteorite NWA 12593, in texturally pristine condition and associated with lithic clasts and the impact melt matrix. Chlorine and hydrogen isotope compositions obtained on apatite in NWA 12593 (δ 37 Cl = +11.3 to +53.1‰; δD = −368 to +1030‰) are significantly greater than in Apollo samples and basaltic lunar meteorites, with a broad range of volatile abundances spanning two orders of magnitude (Cl = 1053–12 337 ppm; H 2 O = 143–4486 ppm). These volatile signatures reveal new insights into the distribution and isotopic heterogeneity of highly volatile elements in areas of the lunar surface not sampled previously and indicate that the lunar interior may have been equally heterogeneous throughout its evolution. The variety of impact melt and lithic material in this sample implies a complex impact history that can contribute to future lunar exploration (e.g. Artemis III) surface activity goals of determining the lunar record of Inner Solar System impact history and volatile distribution throughout the lunar surface and interior.