Quantitative research on effective source rocks of palaeogene liaodong bay area

The effective source rocks were developed during geologic process, which could not only generate hydro-carbon but also expel hydrocarbon. Traditionally,the methods for analyzing effective source rocks are mainly based on determining the low limited of TOC,actual measurement data analysis and simulation experiment. So far,there is not a quantitative research method for the effective source rocks. In this study,according to the expulsion threshold theory,a new quantitative method is formed based on identifying diagram which is established with hydrocarbon po-tential method,and then applied into Liaodong Bay area. It shows that the study area develops three sets of effective source rocks:Ed3 ,Es1+2 and Es3. Among them,the Es3 is the best one. Although dark mudstone is widely developed in Ed2 ,it is not regarded as the effective source rock as it is below the threshold situation of expulsion.