雅鲁藏布江蛇绿岩带的康金拉铬铁矿中发现金刚石  

Diamond discovered from the Kangjinla chromitite in the Yarlung Zangbo ophiolite belt,Tibet.

作　　者：徐向珍[1,2] 杨经绥[1,2] 巴登珠 陈松永[1,2] 方青松[1,2] 白文吉[1,2] 

机构地区：[1]中国地质科学院地质研究所 国土资源部大陆动力学重点实验室,北京100037 [2]中国地质科学院青藏高原大陆动力学研究中心,北京100037 [3]西藏地质局第二地质大队,拉萨850007

出　　处：《岩石学报》2008年第7期1453-1462,共10页Acta Petrologica Sinica

基　　金：中国地质调查局基础地质调查项目(编号1212010610107、1212010610105);国家自然科学基金重大国际合作项目(编号40610098)资助的成果

摘　　要：前人在雅鲁藏布江蛇绿岩带的罗布莎铬铁矿石中发现许多异常矿物,包括金刚石和柯石英等典型压力指示矿物。蛇绿岩型铬铁矿石中为什么会产出金刚石等异常矿物,与其伴生的铬铁矿和蛇绿岩是什么成因,是一个新的重大科学问题。为此,开展了同一蛇绿岩带中康金拉矿区的铬铁矿的人工重砂研究。从1116kg 的铬铁矿样品中发现了近千粒金刚石,以及自然元素、金属互化物、氧化物、硫化物、硅酸盐、钨酸盐和碳酸盐矿物等一批异常矿物。从一个新的矿区发现了大批金刚石,不仅是对罗布莎铬铁矿中存在金刚石的佐证,并且将金刚石的产出规模增加了几个数量级,由此引出蛇绿岩铬铁矿中金刚石是否成矿的新问题。尤其重要的是,从同一蛇绿岩带的不同铬铁矿床中再次发现金刚石,为探讨金刚石及其寄主的铬铁矿和蛇绿岩的成因,提供了新的重要依据。As many unusual minerals including the typical press index minerals such as diamond and coesite have been discovered from Luobusa chromitite in the Yarlung Zangbo ophiolite belt, Tibet, it became a new significant scientific problem that why unusual minerals such as diamond can be generated together with the origin of the ophiolite belt and chromitite associated. Therefore, we carried out the research on the manual heavy mineral of Kangjinla chromitite in the same ophiolite belt, and found thousands of diamonds and their associated minerals including native elements, alloys, oxides, sulphides, silicates, tungstate and carbonates from about 1116kg chromitite. The amount of diamond was discovered from the new chromite deposit not only proved the occurrence of the diamond in Luobusa chromitite, but also greatly improved the output of diamond, and put forward a new problem about diamond mineralization. Especially, that the diamond found again in different chromitite in the same ophiolite belt provided new key evidences for discussing the origin of the diamond and hosted chromite and ophiolite.

关 键 词：金刚石 铬铁矿 康金拉 西藏 

分 类 号：P578.16[天文地球—矿物学] P578.46[天文地球—地质学]