【作者】 廖玉宏；

【导师】 耿安松；

【作者基本信息】 中国科学院研究生院（广州地球化学研究所） ， 地球化学， 2006， 博士

【摘要】 《陆相烃源岩的生排烃机理研究》的研究工作着重于下面几个问题:煤能否生成和排出一定数量的液态烃,各种煤的生排烃具有哪些特征?初次运移和排烃能在多大程度上改变油的组成,哪些因素影响排烃效率和化学组分分馏,机理如何?哪些因素影响煤的生排烃过程中的碳同位素分馏,这些因素对碳同位素分馏的影响到底有多大,其影响的机理又是怎样的?各章节也基本按照这些问题展开。 本研究主要进行了六种烃源岩的生排烃模拟实验及其数值模拟,以及三种烃源岩的初次运移模拟实验,研究了以煤为主的陆相烃源岩的生排烃过程和初次运移过程。取得的成果主要包括以下几个方面: 1) 通过生排烃热模拟实验,完成了对以煤为主的陆相烃源岩的生液态烃烃能力以及生气能力的评价,评估了二次裂解的影响,同时完成了对各烃源岩排烃效率和化学组分分馏的评估; 2) 根据煤的显微组分组成、TOC、HI指数、煤的孔隙度、比表面积等参数,以及在不同热演化阶段的生烃特征,使用GCR模型进行了数值模拟;对影响排烃效率和化学组分分馏的溶胀度(Qv)和大—中孔孔隙度、纳米孔隙度的影响大小及作用机理进行了研究; 3) 评估了各烃源岩生排烃过程中的碳同位素分馏效应,以及初次裂解、二次裂解等影响碳同位素分馏的因素及其影响的大小;证明了不同烃源岩在生排烃过程中存在不同的碳同位素分馏行为;同时也证明了生排烃过程不影响正构烷烃单体碳同位素组成曲线的形状; 4) 通过初次运移模拟实验证明了烃类在不同类型烃源岩中发生初次运移能够产生不同程度的物理碳同位素分馏效应;烃类分子在不同类型烃源岩中的扩散度差别很大,可能是造成同位素分馏的主要原因。更多还原

【Abstract】 The dissertation entitled "The study on the mechanism of generation-expulsion of terrestrial source rocks" has been focusing on the following points: Can coal generate and expel some liquid oil? What are the characteristics of the oil generated by coals? Could expulsion and primary migration affect the compositions of oils from terrestrial source rocks? What factors can impose on the expulsion efficiency and fractionation of oil, and how these factors act? What factors can impose on the carbon isotopic fractionation during generation-expulsion process, to what extent and how they act? The following chapters will answer these questions one by one.Experimental simulation of generation and expulsion of six selected terrestrial source rock samples and the related numerical simulation were carried out in the research. In addition, the experimental simulation of primary migration for three samples among them was also carried out to study the carbon isotopic fractionation during primary migration of oil from source rocks. The following results were achieved:1) By generation-expulsion simulation experiment, the potentials of oil generation of the source rock samples (mainly coals) were evaluated and the influence of secondary crack was also evaluated. The expulsion efficiency and fractional effects during expulsion were evaluated, too.2) Numerical models (GCR) were established to simulate how terrestrial source rocks generate and expel out oil according to the characteristics of source rocks, such as maceral compositions, HI values, porosity, specific surface areas and the different generation behavior at every stage. The research also evaluated how the parameters of Qv and nano-porosity affect expulsion efficiency and fractionation.3) The total carbon isotopic fractionation effect during generation-expulsion process of different terrestrial source rocks was evaluated. It is also evaluated that to what extent the primary crack of different kerogens and secondary crack of hydrocarbons can affect the carbon isotopic fractionation during the generation-expulsion process. It is demonstrated that there are different fractionation effects in different source rocks. The distribution pattern of the carbon isotopic compositions of the individual n-alkanes shows almost no change during this process. All of these should be considered in oil-source correlations.4) The result of the primary migration simulation suggests that there are different carbon isotopic fractionation effects in the primary migration of different source rocks. Diffusion capacities of hydrocarbons in different source rocks are very different, which should be responsible for the carbon isotopic fractionation.更多还原