Features of the geological structure, tectonic development and oil and gas potential of the Chezhen depression (Bohai bay basin)

Abstract

Background. In terms of oil and gas, the territory of the Chezhen depression has been studied insufficiently compared to the neighbouring same-range depressions. These depressions complicate the first-order Jiyang depression, geographically coinciding with the largest Shengli hydrocarbon field. In recent years, much geological and geophysical information about the oil geologyof the Chezhen depression has been accumulated, which allows its prospecting oil and gas potential to be assessed.Aim. To reveal regular features of the geological structure and location of oil deposits in the Chezhen depression in order to support the prospecting and exploration work within the Chezhen block of the Shengli field.Materials and methods. A comprehensive analysis of literature data and collected materials was conducted. A historical and geodynamic study of the evolution of the studied area according to literature data was carried out, along with an analysis of the most recent geological and geophysical information and exploration data based on the materials of the “Shengli AKOO Sinopek” oil company. The analysis was based on the data from 52 drilling wells and the results of seismic surveys performed in the central part of the Chezhen depression.Results. Specific features of the block geological structure of the area under study were established, which formed under the repeated influence of large-scale horizontal tectonic movements occurring at different periods of geological history. The role of the most recent fault system in the modern spatial distribution of oil deposits was determined.Conclusions. Our studies demonstrate a great prospecting potential of the Chezhen depression territory, where the discovery of new industrial oil deposits can be expected.