Abstract: In this paper,the optical properties,origin and distribution pattern of vitrinite occurring in different kinds of organic rocks and oil source rocks are investigated in detail,and a preliminary classification is suggested in which vitrinite are divided into three types according to its origins hydrogenrich vitrinite(A),normal vitrinite(B)and reworked vitrinite(C).A quantitative discussion is made for the reflectance differances between this three types and their evolution pattern during thermal maturation.It is pointed out that the selection of maturation parameter for oil source rocks should depend on their organic petrological characteristics.In low mature stage,the reliability of vitrinite reflectance as a maturation parameter will increase as the organic type of the oil source rock becomes worse.However,in the over mature stage,the reflectances of the three types of vitrnite become gradually consistent,and all of them can be used as a maturation parameter.

摘要： 本义详细研究了我国不同类型有机岩及生油岩中镜质组的光学特征、成因及分布规律,初步提出将镜质组划分为3种成因类型:富氢镜质组(A),正常镜质组(B)及再沉积镜质组(C);定量探讨了这3类镜质组反射率的差别及其随成熟度的演化规律.文中指出,生油岩成熟度参数的选取,应当依据其有机岩石学特征,在低成熟阶段,镜质组反射率作为成熟度指标的可靠性随源岩有机质类型的变差而增强;到过成熟阶段,3类镜质组反射率渐趋一致.

关键词: 镜质组反射率, 生油岩, 不同类型, 成熟度指标, 分布规律, 有机质类型, 有机岩, 成熟阶段, 油页岩, 腐殖煤