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Nakhlites are a group of Martian meteorites, named after the first one, Nakhla meteorite. Nakhlites are igneous rocks that are rich in augite and were formed from basaltic magma about 1.3 billion years ago. They contain augite and olivine crystals. Their crystallization ages, compared to a crater count chronology of different regions on Mars, suggest the nakhlites formed on the large volcanic construct of either Tharsis, Elysium, or Syrtis Major Planum.〔Treiman, A.H., ("The nakhlite meteorites: Augite-rich igneous rocks from Mars" ) - (PDF) Chemie der Erde 65, p. 203-270, (2005). URL accessed July 30, 2011.〕 It has been shown that the nakhlites were suffused with liquid water around 620 million years ago and that they were ejected from Mars around 10.75 million years ago by an asteroid impact. They fell to Earth within the last 10,000 years.〔 ==Samples== The following samples of nakhlites are known. *Nakhla meteorite (about 40 samples, total estimated weight ), vicinity of Nakhla, Abu Hommos district, Alexandria Governorate, Egypt, 1911 *Governador Valadares meteorite 〔("Mineralogy of nakhlite Martian meteorites: Implications for their relative burial depths " ), Mikouchi, T.; McKay, Gordon; Miyamoto, M., 2006, NASA Technical Reports Server〕 *Lafayette meteorite, 800g, before 1931 〔("Lafayette - 800 grams Nakhlite" ), Martian Meteorite Compendium, C. Mayer, 2012〕 *NWA817, 104g, Morocco, 2000 〔(NWA 817 – 104 grams Nakhlite )〕 *NWA998, 456g, Morocco, 2001 〔(NWA 998 – 456 grams Nakhlite )〕 *Y000593 (Yamato 593), 〔http://curator.jsc.nasa.gov/antmet/mmc/Y000593.pdf〕〔Imae N., Okazaki R., Kojima H. and Nagao K. (2002a) The first Nakhlite from Antarctica (abs#1483). Lunar Planet. Sci. XXXIII. Lunar Planetary Institute, Houston〕 *Y000749, 〔〔Imae N., Ikeda Y., Shinoda K., Kojima H. and Iwata N. (2002c) Two Nakhlites from Antarctica: Y000593 and Y000749 (abs). Antarctic Meteorites XXVII, 45-47. Nat. Inst. Polar Res., Tokyo〕 *Y000802, 22g 〔 *MIL 03346 Miller Range, Antarctica〔 *MIL 090030, MIL 090032, and MIL 090136, Miller Range, Antarctica〔()〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Nakhlite」の詳細全文を読む スポンサード リンク
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