湘中南龙潭煤系不同演化程度煤的生烃潜力研究

STUDY ON HYDROCARBON-GENERATING POTIENTIAL OF DIFFERENT EVOLUTIONARY STAGE CAOLS OF LONTAN FORMATION IN MIDDLE-SOUTHERN OF HUNAN

以有机岩石学和有机地球化学相结合的手段,对湘中南二叠纪龙潭煤系中不同演化阶段煤的煤岩组成、有机质丰度、生烃阶段和生烃潜力进行了研究,指出其中的气煤、肥煤和焦煤是具有较高生烃潜力的烃源岩。

In order to approach the possibility of hydrocarbon generation of the longtan Fromation in the middle-southern of Hunan,the paper studied the maceral composition and geochemical characterictics of coal samples which rank from gas coal to high anthracite.The results show that the gas coal,fat coal,and coking coal are in the evolutionary stage of maturity,and hydrogen-rich macerals including exinite and hydrogen-rich vitrinite are higher in content.Furthermore,their contents of bitumen'A'are in the range of 14.17～15.77mg/g,S_1+S_2 are from 101.90 to 163.81mg/g.coal.Although their transformation ratios are all lower than oil source rock,they are a kind of good source rock for generating condensate oil and wet gas.However,the lean coal and all of anthracite are beyond the evolutionary stage of maturity,and hydro- gen-rich macerals are low,so their indice of hydrocarbon-generating potential are correspondingly low,but they are a kind of gas source rock