四川赤普铅、锌矿床生物标志化合物特征研究

赤普铅、锌矿床的矿体中发育大量沥青，铅、锌矿化形成与沥青密切相关。应用族组分分离和定量及饱和烃色—质分析等方法对铅、锌矿中的沥青族组分和生物标志物进行了研究，并对其地质意义进行了探讨。通过研究取得如下认识:（1）铅、锌矿床内有机质主要来自碳酸盐岩，其次来自页岩，没有陆源有机质的加入；这种混合来源特征受到不同来源成矿流体作用的影响。（2）矿区内有机质反映了热液流体经历了还原、高盐度的物理化学过程。（3）矿区内有机质成熟度高，主要为炭质沥青，反映有机质的演化程度较高；矿体内有机质与围岩内有机质成熟度类似，反映它们经历了类似的地质作用过程。（4）有机质还原碳酸盐岩中的硫酸盐岩，产生还原硫，为铅、锌等硫化物的沉淀创造条件。（5）成矿流体中烃类含量比较高，推断已经演化到高成熟阶段的有机质可能以古油气藏的形式参与了成矿作用；有机质在与含矿流体混合过程中扮演着还原剂的角色。

Research on the Biomarker from Chipu Pb-Zn Deposit, Sichuan

The Chipu lead zinc deposit has closely associated with the bitumen. There have a large number of bitumen grown up with lead zinc sulfide hosted by carbonate rocks. Through ethnic separation, quantitative and saturated hydrocarbons chromatogram mass spectrum analysis, we researched on the ethnic composition and biomarker of bitumen and discussed their geological significance. The conclusions are shown as follows: (1) Organic matter in lead zinc deposits mainly came from carbonate rocks, minor came from the shale, and no continental organic matter added in it. Characteristics of this kind of mixed origin could be affected by different sources of ore forming fluid. (2) Organic matter in deposit implies that the hydrothermal fluids suffered from the physical and chemical processes of high reduction and high salinity. (3) Organic matter, which hosted by lead zinc ore and dolostone, with high maturity, belongs to carbon bitumen, which reflect the evolution of higher levels of organic matter. Organic matters in ore and host rock have a similar maturity, and reflect a similar geological process. (4) Organic matter reduced the sulfate in carbonate rocks, and resulted in reduced sulfur to create the conditions for lead and zinc sulfide precipitation. (5) ore forming fluids in the hydrocarbon content is relatively high, it inferred that high mature stage of evolution of organic matter may be the formation of the ancient reservoir involved in the mineralization. The organic matter plays a role of reducing agent during mixing with ore bearing fluid.