The Stratigraphic Correlation Between 3rd Member And 4th Member Of Shahejie Fm Of Dongpu Depression

The unification of stratigraphic correlation is the base of the study of petroleum geology,but there are many questions in the study of stratigraphic correlation of Dongpu Depression.This makes it very difficult to study the deposition , structure,and so on.At the same time,this brings many inconveniences to deployment and management.The predecessors have done many works in stratigraphic correlation,and get many results.This gets up the base for today's work.But Dongpu Depression is very difficult,and there are large changements in ithologic character and lithofacies,so many problems can be resolve,such as stratigraphic correlation of 3rd member and 4th member of Shahejie Fm,and so on.This paper focused on 3rd member and 4th member of Shahejie Fm where there are quite a few contradictions in stratigraphic correlation. It made out the corresponding relationship of the sand groups. Twelve coring wells were chosen from Sand 3-Sand 4 to perform palaeontology identification and analysis. According to the palaeontology grouping and fossil assemblage in other hydrocarbon areas in Bohai Bay, the division was discussed in four factors: palaeontology evolution, lithology and electricity features, depression evolution and seismic phase reflection. Conclusion: the division between 3rd member and 4th member of Shahejie Fm is the stabilized mud shale lying at the top of a set of continuously deposited salt rock that exists over the low-resistivity red interval in Wenliu, Hu Zhuangji and Mazhai areas.This study of stratigraphic correlation between 3rd member and 4th member of Shahejie Fm of Dongpu Depression is very important for structural evolution, deposition and remigration of Dongpu Depression.This makes it easy for exploratory development.