Various combinations of diamond, moissanite, zircon, quartz, corundum, rutile, titanite, almandine garnet, kyanite, and andalusite have been recovered from the Dangqiong peridotites. More than 80 grains of diamond hav...Various combinations of diamond, moissanite, zircon, quartz, corundum, rutile, titanite, almandine garnet, kyanite, and andalusite have been recovered from the Dangqiong peridotites. More than 80 grains of diamond have been recovered, most of which are pale yellow to reddish-orange to colorless. The grains are all 100-200 μm in size and mostly anhedral, but with a range of morphologies including elongated, octahedral and subhedral varieties. Their identification was confirmed by a characteristic shift in the Raman spectra between 1325 cm^-1 and 1333 cm^-1, mostly at 1331.51 cm^-1 or 1326.96 cm^-1. Integration of the mineralogical, petrological and geochemical data for the Dongqiong peridotites suggests a multi-stage formation for this body and similar ophiolites in the Yarlung-Zangbo suture zone. Chromian spinel grains and perhaps small bodies of chromitite crystallized at various depths in the upper mantle, and encapsulated the UHP, highly reduced and crustal minerals. Some oceanic crustal slabs containing the chromian spinel and their inclusion were later trapped in suprasubduction zones（SSZ）, where they were modified by island arc tholeiitic and boninitic magmas, thus changing the chromian spinel compositions and depositing chromitite ores in melt channels.展开更多
The 〉 2000-kin-long Indus-Tsangpo suture zone （ITSZ） in southern Tibet marks the boundary between the India and Eurasia plates and contains the remnants of the Neotethyan oceanic lithosphere, ophiolitic mé1anges,
The first diamonds from ophiolite were found in peridotite of Luobusa ophiolite along Yarlung Zangbu suture zone in Tibet, China （IGCAGS, 1981）, and then more and more diamonds found in harzgurgite （Bai et al., 199...The first diamonds from ophiolite were found in peridotite of Luobusa ophiolite along Yarlung Zangbu suture zone in Tibet, China （IGCAGS, 1981）, and then more and more diamonds found in harzgurgite （Bai et al., 1993; Yang et al., 2007a; Robinson et al., 2014; Xu et al.,展开更多
基金funded by grants from Sinoprobe-05-02 from the Ministry of Science and Technology of China,the NSF China(Nos.41502062,40930313,40921001,41202036)the China Geological Survey(Nos.12120115027201,12120114061801,2014DFR2127C)from the Institute of Geology,Chinese Academy of Geological Sciences(J1526)
文摘Various combinations of diamond, moissanite, zircon, quartz, corundum, rutile, titanite, almandine garnet, kyanite, and andalusite have been recovered from the Dangqiong peridotites. More than 80 grains of diamond have been recovered, most of which are pale yellow to reddish-orange to colorless. The grains are all 100-200 μm in size and mostly anhedral, but with a range of morphologies including elongated, octahedral and subhedral varieties. Their identification was confirmed by a characteristic shift in the Raman spectra between 1325 cm^-1 and 1333 cm^-1, mostly at 1331.51 cm^-1 or 1326.96 cm^-1. Integration of the mineralogical, petrological and geochemical data for the Dongqiong peridotites suggests a multi-stage formation for this body and similar ophiolites in the Yarlung-Zangbo suture zone. Chromian spinel grains and perhaps small bodies of chromitite crystallized at various depths in the upper mantle, and encapsulated the UHP, highly reduced and crustal minerals. Some oceanic crustal slabs containing the chromian spinel and their inclusion were later trapped in suprasubduction zones（SSZ）, where they were modified by island arc tholeiitic and boninitic magmas, thus changing the chromian spinel compositions and depositing chromitite ores in melt channels.
文摘The 〉 2000-kin-long Indus-Tsangpo suture zone （ITSZ） in southern Tibet marks the boundary between the India and Eurasia plates and contains the remnants of the Neotethyan oceanic lithosphere, ophiolitic mé1anges,
基金funded by grants from Sinoprobe-05-02 from the Ministry of Science and Technology of Chinathe NSF China (Nos. 40930313, 40921001, 41202036)+1 种基金the China Geological Survey (Nos. 1212011121263, 12120114061801, 2014DFR2127C)project from Institute of Geology, Chinese Academy of Geological Sciences (J1526)
文摘The first diamonds from ophiolite were found in peridotite of Luobusa ophiolite along Yarlung Zangbu suture zone in Tibet, China （IGCAGS, 1981）, and then more and more diamonds found in harzgurgite （Bai et al., 1993; Yang et al., 2007a; Robinson et al., 2014; Xu et al.,
