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您的检索式：作者名="DAIMingquan"
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| 1 | Silicon-rutile - an ultra-high pressure (UHP) mineral from an ophiolite显示文摘Silicon(Si)-rutile separated from the Luobusa podiform chromitite in the Yarlung Zangbo ophiolite of southern Tibet is typically about 50 μm×50 μm×200 μm in size and consists mainly of SiO2 and TiO2. The average mineral formula is (Ti0.82Si0.18)O2. Powder X-ray diffraction data show that it is tetragonal in form, and the unit cell dimensions and other parameters are: a=4.591(2), c=2.946(2), v=62.09(5)3, c/a=0.6415, with a molar volume about 5% smaller than rutile (JCPDS, 21-1276). The Si4+ ions in silicon rutile are six-coordinated, and are substituted for Ti4+ in the rutile structural sites. The Si-rutile, along with other associated ultra-high minerals discovered in the chromitite, such as octahedral silicate, silicon-magnesium spinel (Si4+ ions are six-coordinated), diamond, and intergrown of SiO2 and FeO phases, probably originated from the transition zone or the lower mantle, and were brought to shallow levels beneath an oceanic spreading ridge by an upwelling superplume. | YANGJingsui BAIWenji FANGQingson YANBinggang SHINicheng MAZhesheng DAIMingquan XIONGMing | 2003 | Progress in Natural Science:Materials International2003，13，7： | 14 |
| 2 | An X-Ray Diffraction Study of an Inclusion in Diamond from the Luobusha Chromite Deposit in Tibet,China显示文摘Diamond was found in podiform chromitites of ophiolite and harzburgite from Luobusha, Tibet. There are silicate inclusions in some diamond grains from this area. In the present work, the CCD (charge coupled detector) technology of X-ray powder diffraction was applied to the study of the inclusion in diamond from the ophiolite of Tibet. Diffraction patterns are obtained even though the inclusion is only 20 μm in crystal size. The results show that the inclusion in diamond consists of talc and clinochrysotile. Therefore, it is clear that the diamond from the ophiolite of Luobusha, Tibet, is natural diamond rather than a synthetic one. | SHINicheng BAIWenji MAZhesheng FANGQingsong XIONGMing YANBinggang DAIMingquan YANGJingsui | 2003 | Acta Geologica Sinica(English Edition)2003，77，3： | 1 |
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