Mineralogy Petrology and Oxygen Fugacity of the Lapaz Icefield Lunar Basaltic Meteorites and the Orgin of Evolved Lunar Basalts

摘要

LAP 02205 is a 1.2 kg lunar mare basalt meteorite found in the Lap Paz ice field of Antarctica in 2002. Four similar meteorites were also found within the same region and all five have a combined mass of 1.9 kg (LAP 02224, LAP 02226, LAP 02436 and LAP 03632, hereafter called the LAP meteorites). The LAP meteorites all contain a similar texture, mineral assemblage, and composition. A lunar origin for these samples comes from O isotopic data for LAP 02205, Fe/Mn ratios of pyroxenes, and the presence of distinct lunar mineralogy such as Fe metal and baddeleyite. The LAP meteorites may represent an area of the Moon, which has never been sampled by Apollo missions, or by other lunar meteorites. The data from this study will be used to compare the LAP meteorites to Apollo mare basalts and lunar basaltic meteorites, and will ultimately help to constrain their origin.