湘西地区晚震旦世—早寒武世黑色岩系的生物和有机质及其成矿作用

BIOTA AND ORGANIC MATTER IN LATE SINIAN AND EARLY CAMBRIAN BLACK ROCK SERIES OF WEST HUNAN AND THEIR SIGNIFICANCE TO METALLIZATION

根据湘西地区晚震旦世—早寒武世黑色岩系的分布、生物群类型与分布及其与金属元素富集的关系 ,提出黑色岩系中的Ag -V ,Mo和Ni-P的富集成矿分别与浮游菌藻、多细胞植物和介壳化石的分布发育关系密切。黑色岩系分散有机质红外光谱研究表明 ,区内晚震旦世—早寒武世地层黑色岩系的有机质演化处于过成熟阶段 ,且垂向分布存在明显倒置的特点。探讨了黑色岩系地层分散有机质成熟度倒置的原因以及有机质及其演化与金属元素富集成矿的关系。

According to distribution and types of black rock series and biota as well as their relationships with enrichment of metals,it has been put forwards that concentration of Ag V,Mo and Ni P shows close relation to occurrence and development of the bacteria or shelly fossils,multi cell plants and vendotaenides,respectively. IR spectroscopic analysis shows that organic matter in Late Sinian and Early Cambrian strata is over matured. Due to the effect of enhancement of organic maturation by hydrothermal fluids,the Upper Sinian and Lower Cambrian had a reverse organic maturity profile in most areas of West Hunan. The organic absorption resulted in enrichment of Ag,V,Ni,Mo and U,and the gold might be migrated by hydrothermal fluids.