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Gillet, P; Barrat, J; Beck, P; Marty, B; Greenwood, R; Franchi, I; Bohn, Marcel; Cotten, J. |
Northwest Africa (NWA) 1950 is a new member of the lherzolitic shergottite clan of the Martian meteorites recently found in the Atlas Mountains. The petrological, mineralogical, and geochemical data are very close to those of the other known lherzolitic shergottites. The meteorite has a cumulate gabbroic texture and its mineralogy consists of olivine (FO66 to FO75), low and high-Ca pyroxenes (En(78)Fs(19)Wo(2)-En(60)FS(26)W(14); En(53)Fs(16)Wo(31)-En(45)Fs(14)Wo(41)), and plagioclase (An(57)Ab(41)Or(1) to An(40)Ab(57)Or(3); entirely converted into maskelynite during intense shock metamorphism). Accessory minerals include phosphates (merrillite), chromite and spinels, sulfides, and a glass rich in potassium. The oxygen isotopic values lie on the fractional... |
Tipo: Text |
Palavras-chave: Meteorites; Atlas Mountains; Shergottite; Lherzolitic. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-900.pdf |
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