摘要
在对位于苏北榴辉岩分布区中国大陆科学钻探工程CCSD5000多m主孔岩心进行岩矿鉴定的过程中,普查发现存在各种各样的脉体,可大致分为四大系列(1)与超高压/高压变质阶段有关的脉体系列;(2)与减压部分熔融阶段有关的脉体系列;(3)与退变质(主要绿帘角闪岩相和绿片岩相)有关的脉体系列;(4)折返晚期超低压-低温热液脉体.尤其特别的是于3578.5~4006m深度发现了大量特殊的富含稀土矿物的脉体.CCSD主孔岩心的脉体分布广泛、类型繁多,有的与矿化作用密切有关,在成因上可能属于大规模地质流体交代的结果.
A variety of veins were discovered during the observation and identification of rocks from the main hole of CCSD (the China Continental Scientific Drilling Project), which is located at the eclogite area in North Jiangsu. These veins can be divided into four series: ① related to the UHP/HP stage; ② related to the decompression and partial melting stage; ③ related to the retrograde metamorphism stage; ④ related to the late exhumation stage. Especially, large numbers of REE-mineral-rich veins were found at depths of 3578.5-4006m. These veins from the CCSD main hole were widely distributed and some were closely related to mineralization. In genesis, they may be the result of geological fluid metasomatism on a large scale.