Lithofacies type and characteristics of fine - grain sedimentary rock of the second member of Kongdian formation in Cangdong sag

Fine-grained sedimentary rocks in lacustrine basin are composed of a variety of different types of lithofacies.However, the classification of fine-grained sedimentary rocks is based on the grain size.And the phenomenon that... [ view full abstract ]

Fine-grained sedimentary rocks in lacustrine basin are composed of a variety of different types of lithofacies.However, the classification of fine-grained
sedimentary rocks is based on the grain size.And the phenomenon that the meaning of the term of the fine grained sedimentary rocks is always used vaguely has brought inconvenience in the exploration and development of shale oil and gas.So it is necessary to establish a set of relatively systematic, independent of fine-grained sedimentary lithofacies type program.In this paper, the fine-grained sedimentary rocks of the XX well in Cangdong Sag were sampled intensively and we classified the types of rock. through the tecniques such as the observation of the core, thin section identification, X ray diffraction analysis, etc.On the basic of the types of rock,we divided the fine-grained sedimentary rock of Cangdong sag into 3 main lithofacies types,such as carbonate lithofacies ,fine-grained felsic sedimentary lithofacies,fine mixed sedimentary lithofacies and 8 detailed types with combining the sedimentary structure,organic matter content and color feature.In the last,we summarized the characteristics of all kinds of lithofacies.