南华北地区石炭-二叠纪煤系生烃潜力与二次生烃探讨

综合运用岩石热解、有机岩石学及有机地球化学等方法,对南华北地区石炭-二叠纪煤系烃源岩有机质丰度、类型以及成熟度和热演化史进行了分析,综合评价了烃源岩的生烃潜力。评价结果表明,石炭系(太原组+本溪组)烃源岩要好于二叠系山西组、石盒子组;有机质类型以Ⅲ型干酪根为主、Ⅱ型干酪根为辅;有机质热演化程度大部分处于成熟-高成熟阶段,部分地区达到过成熟,以生气为主。文中结合构造-热演化史资料分析了煤系二次生烃的条件,指出谭庄-沈丘凹陷和倪丘集凹陷初始成熟度较低,且具有合适的埋藏史类型,并有二次生烃油气勘探前景。 

Discussion on hydrocarbon generation potential and secondary hydrocarbon generation of organic matter from Permo-Carboniferous coal measures in the southern North China

On the basis of analysis about the abundance and the types of Permo-Carboniferous coal measures organic matters in the southern North China area,and research on the source rocks' maturity and the thermal evolution history,this article evaluates synthetically the hydrocarbon generation potential by means of organic petrology,Rock-Evel and geochemistry.It is concluded that hydrocarbon source rocks of Carboniferous(Taiyuan Formation and Benxi Formation) are better than that of Permian(Shanxi Formation and Shihezi Formation);the type Ⅲ of organic matter is dominant and the type Ⅱ is less.Thermal evolution of the most organic matter is in mature stage and high-mature stage,or even over-mature in part area,they are all generating gas.Through systematic research the condition about secondary hydrocarbon generateon with the tectonic-thermal evolution history,point out that the Tanzhuang-Shenqiu Depression and the Niqiuji Depression have lower beginningmaturity and superior burial history conditions for secondary hydrocarbon generation and can lead to form gas field.