リンク集 KURENAI: Kyoto University Research Information Repository

タイトル: Discovery of moganite in a lunar meteorite as a trace of H2O ice in the Moon’s regolith著者: Kayama, Masahiro; Tomioka, Naotaka; Ohtani, Eiji; Seto, Yusuke; Nagaoka, Hiroshi; Götze, Jens; Miyake, Akira; Ozawa, Shin; Sekine, Toshimori; Miyahara, Masaaki; Tomeoka, Kazushige; Matsumoto, Megumi; Shoda, Naoki; Hirao, Naohisa; Kobayashi, Takamichi抄録: Moganite, a monoclinic SiO2 phase, has been discovered in a lunar meteorite. Silica micrograins occur as nanocrystalline aggregates of mostly moganite and occasionally coesite and stishovite in the KREEP (high potassium, rare-earth element, and phosphorus)–like gabbroic-basaltic breccia NWA 2727, although these grains are seemingly absent in other lunar meteorites. We interpret the origin of these grains as follows: alkaline water delivery to the Moon via carbonaceous chondrite collisions, fluid capture during impact-induced brecciation, moganite precipitation from the captured H2O at pH 9.5 to 10.5 and 363 to 399 K on t ...