月球隕石NWA16470與NWA16471的類型劃分和成對性分析

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Abstract： Lunar meteorites serve as superior carriers for lunar research compared to returned samples. In this study， we investigate the petrography and mineralogy of two newly discovered lunar meteorites，NWA l6470 and NWA 16471.The results show that NWA 16470 and NWA 16471 are anorthositic gabbro lunar polymict breccia meteorites. The lithic clastsconsist largelyof anorthosite，gabbro，and troctolite.The mineral detrital is mainly composedof plagioclase，pyroxene，and olivine.Trace phases include ilmenite，troilite，chromite，and Fe and Ni metals.The mineral chemistry of the two meteorites is as folows： the composition of plagioclase is homogeneous （NWA 16470： An96.0～97.2Ab2.5～3.9 ， NWA 16471： An94.0-97.3Ab2.7～5.7） ; the pyroxene is mainly augite， pigeonite， and hypersthene （NWA 16470： Fs23.9～35.3Wo4.0～28.2En44.3～71.2. ，NWA 16471： Fs12.0-37.8Wo4.0-41.1En43.2-73.2） ； and the olivine has a wide range of components （NWA 16470： Fo54.5～80.2 ，NWA 16471： Fo52.5～74.3） .The characteristics of trace elements are consistent withotherreported lunar meteorites.Additionally，both meteoritesshowanenrichmentoflightrareearthelements and a positive anomaly inEu，with SEu values ranging from 2.1 to16.9.Our analysis is basedon the rock texture， mineral composition， detrital composition， whole rock composition，and trace element relationships （Sm-Sc and Eu/Sm-Sc of these meteorites，including acomparison with lunar meteorites previouslystudied.Itisconcludedthat themajorityof the components of NWA 16470 and NWA 16471 are from the lunar highlands， with a smallportion of lunar mare. Although NWA 16470 and NWA l6471 have the same discovery time， place and appearance， they have certain diferences in terms of mineral and chemical composition，implying they cannot be identified as a meteorite pair.

Key words： lunar meteorites；lunar breccia； petromineralogy； paired meteorites

月球隕石作為月球物質(zhì)的重要來源，為研究月球表面組成和演化提供了關(guān)鍵線索（歐陽自遠(yuǎn)，2005;Korotev，2005）。（剩余16768字）