烃源岩生排烃组分法模型研究与应用

本文提出了一种新的烃源岩生排烃组分法模拟模型。组分法生烃模型根据热模拟实验得到的组分产率曲线模拟烃源的生烃史。排烃模型包括开放体系模型和间歇开放体系模型，分别用于模拟以压实作用为主要动力的孔隙排烃和以异常高压为主要动力的微裂缝排烃。这一模型根据孔隙温度、压力和烃类组成，采用热力学方法模拟孔隙体系流体体积和相态的变化、不同组分在各相中的分布，并由此求出各组分的排出量和总排烃量。对陕甘宁盆地古生界源岩生排烃史的模拟结果表明，该模型具有实用价值。

Compositional Models of Petroleum and Expulsion from Source Rocks and Generation in Their Application

The new compositional models of hydrocarbon generation in and expulsion from source rocks wereproposed in this paper. The compositional model of hydrocarbon generation is based on the com posi do nalproductivity of source rocks vs. thermal maturity derived from thermal simulation experiment in labora-tory. The compositional model of hydrocarbon expulsion includes open system model and intermittentlyopen system model. The open system model describes the process of hydrocarbon expulsion throughpores of source rocks forced by compaction,and the intermittently open system model describes the pro-cess of hydrocarbon expulsion through microfractures forced by abnormally high fluid pressure. The changes of fluid volume and phases in the pore system and the distribution of hydrocarbon compositionsin different phases were calculated with thermodynaer cprinciples based on the temperature pressureand the fluid composition in the pore system. Thus, the expulsion history of hydrocarbon compositionsand the total expulsion amount can be simulated based on the difference between fluid volume and porevolume of source rocks and the distribution of hydrocarbon compositions in different phases. The resultof these models applied to the Paleozoic of the Ordos basin has shown the practical value of the models.