Mineralogy of Antarctic lunar meteorites and differentiated products of the lunar crust
The mineralogy of clasts containing pyroxenes and glassy matrices of lunar meteorites, Yamato-791197 (Y-791197) and Allan Hills A81005 (ALHA81005) has been studied by an electron microprobe and an analytical transmission electron microscope (ATEM). A rare brown pyroxene-rich clast (HPF) consists of...
| Main Authors: | , , |
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| Format: | Report |
| Language: | English |
| Published: |
Mineralogical Institute, Faculty of Sciences, University of Tokyo/Mineralogical Institute, Faculty of Sciences, University of Tokyo/Mineralogical Institute, Faculty of Sciences, University of Tokyo
1986
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| Subjects: | |
| Online Access: | https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=1951 http://id.nii.ac.jp/1291/00001951/ https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=1951&item_no=1&attribute_id=18&file_no=1 |
| Summary: | The mineralogy of clasts containing pyroxenes and glassy matrices of lunar meteorites, Yamato-791197 (Y-791197) and Allan Hills A81005 (ALHA81005) has been studied by an electron microprobe and an analytical transmission electron microscope (ATEM). A rare brown pyroxene-rich clast (HPF) consists of hedenbergite, Ca-poor iron-rich pyroxene, plagioclase, fayalite, silica and ilmenite. This exotic component may be a differentiated product of the lunar crust or an iron-rich portion of a basalt. The evolutionary trend of Y-791197 from spinel troctolite to anorthosite in the An content vs. Mg/(Mg+Fe) diagram is similar to that of ALHA81005 and is located between the Mg-rich suite of rocks and ferroan anorthosite. It is difficult to prove that this trend represents a single differentiation and that the HPF clast is on the extension of this trend, because the data appear to define a trend of extremely steep slope. The glass in the matrix of ALHA81005 is devitrified on the TEM scale. |
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