湘黔下寒武统黑色岩系有机成矿地球化学研究  

The Organic Mineralization Geochemistry Research of the Black-Rock-Series in the Lower Cambrian in Hunan and Guizhou Provinces

作　　者：江永宏[1,2] 

机构地区：[1]中国地质调查局发展研究中心情报室,北京100037 [2]中国地质大学地质过程与矿产资源国家重点实验室,北京100083

出　　处：《西北地质》2013年第3期156-166,共11页Northwestern Geology

基　　金：国家自然科学基金(40073012);国家重点基础研究发展规划(G1998040800);国土资源大调查(199910200264;20001020223023;200313000068-02)项目资助

摘　　要：通过黑色岩系有机成矿地球化学研究,证实湘、黔两地镍钼矿床都经历了后生期的构造热变质事件,贵州遵义的地史上生过油,可以认为有机质的热成熟过程伴随有机质的热解、流体迁移、生烃、成气、排气、生油等过程。磷块岩的姥胶烷含量Pr(3.33%)和植烷含量(5.84%)均为最高,说明其生物成因最为显著。因为PGE元素的富集与有机质有关,不同热演化的成熟度不同,对应的热演化史也不相同,故可以认为有机质的芳构化效应导致PGE金属元素的超常富集。类似于其他产油地区,同样具有高饱和烃、低芳烃、高非烃、低沥青质的特征,说明为石油沥青,贵州遵义样品的甲基菲比和二甲基菲比为最高值,张家界柑子坪金属富集层的二甲基菲比1.36为最高值,也同样说明成熟度最高。By virtue of the organic mineralization geochemistry research, this article validates that the deposits in Hunan and Guizhou have undergone epigenetic structural hydrothermal metamorphism events. According to the geo-history in Zunyi of Guizhou province, oil has been produced in this region, thus we can acknowledge that the thermal maturation process of the organic matter was accompanied by the processes of pyrolysis, fluid migration, hydrocarbon pro- duction, gas formation, exhausting, and oil formation. The contents of pristine （Pr） and the phytene （Ph） in the phosphorite are the highest, which are 3.33~ and 5.84% respectively, indicating the most remarkable biogenesis. Because the enrichment of PGE elements is related to organic matter, there is large discrepancy between the maturity of different thermal evolutions as well as their corresponding thermal evolution history. Consequently, it is believed that the aromatic structure effect of the organic matter will lead to the abnormal enrichment of the PGE metal elements. Similar to other oilfields, the study area boasts the same typical characteristics of high saturation hydrocarbon, low aromatic hydrocarbon, high non-hydrocarbon and low bitumen, indicating that the ore bed is oil bitumen. In addition, the methyl phenanthrene rate and dia- methyl phenanthrene rate in the sample from Zunyi of Guizhou is the highest, while the dia- methyl phenanthrene rate as 1.36 of the metal enrichment bed in Ganziping of Zhangjiajie, Hunan province is also the highest, confirming that both oilfields are of highest maturity.

关 键 词：湘黔 下寒武统 黑色岩系 有机成矿 地球化学 

分 类 号：P593[天文地球—地球化学]