Lunar Meteorites Nwa 2700, Nwa 2727 and Nwa 2977: Mare Basalt/gabbro Breccias with Affinities to Nwa
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چکیده
NWA 2700 and NWA 2977 Paired With NWA 773: NWA 2700 is a 31.7 gram stone consisting of small gabbro clasts plus regolith breccia matrix (see Figure 1). The olivine gabbro contains ~50 vol.% olivine (Fa29.3-34.7; FeO/MnO = 94), pigeonite (Fs2228.3Wo5.6-10; FeO/MnO = 52), augite (Fs13.2Wo38.5), plagioclase and minor maskelynite (An89), Ba-rich alkali feldspar (Or92An4, BaO up to 8.9 wt.%), Crspinel, ilmenite, phosphate, and troilite. The breccia contains abundant small olivine gabbro clasts and sparse clasts of fine-grained basalt (containing pyroxenes zoned from Fs44W o 29 to Fs58W o 2 3 (FeO/MnO = 57), plagioclase (An90), ilmenite and ferropigeonite (Fs80.8Wo14). Other components are fayalite (Fa91) + hedenbergite (Fs60.3Wo32.7) + silica symplectites, clear to yellow glass spherules, agglutinates, fayalite (Fa95.6)+silica, ulvöspinel, K-Sirich glass (8.8 wt.% K2O) and a silica polymorph.
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