Hydrodynamic Field And Its Interaction With Tectonics Of The Central Combination In The North Of Songliao Basin

The hydrodynamic field is a key factor affecting the migration and accumulation of oil and gas,which controls the distribution of oil and gas in the basin to a considerable extent.According to the plane and profile characteristics of the hydrodynamic field in the Songliao Basin,the evolution history of the hydrodynamic field in the Songliao Basin is analyzed and its interaction with the tectonics is studied.Based on the previous studies,this paper analyzes the characteristics of the hydrodynamic field in the northern part of the Songliao Basin,which is characterized by the undercutting effect of mudstone and the spatial division of reservoir pressure.In the Songliao Basin,four sets of undervoltage mudstones were developed,and the basin was divided into five layers in the vertical direction,which corresponded to the five major oil and gas combinations respectively.The reservoir hydrodynamic field formed three abnormal pressure systems,Depression as the center of the high-pressure system,Sanzhao depression and its east of the abnormal low-pressure system and the northeast uplift belt and the north dumping with the abnormal low-pressure system.The evolution of the late hydrodynamic field in the Songliao Basin is based on the compaction-driven compaction flow to the evolution of the fluid driven by the terrain,which is affected by the later tectonic activity and the abnormal pressure migrates westward in the section.At the end of the Yaojia Formation,the fluid pressure gradually accumulates before the end of the chalk,and the hydrodynamic field is driven by the abnormal pressure.At the end of the chalk period,the anomalous pressure gradually dissipates and the hydrodynamic field is driven by the abnormal pressure Mainly evolved into the north by the characteristics of atmospheric precipitation infiltration.The late tectonic activity created the special three abnormal pressure systems in the Songliao Basin,and the hydrodynamic field of the basin had a significant effect on the structural pattern and tectonic reversal of the depression in the basin.Abnormal pressure hydrodynamic field reduces the friction coefficient and compressive strength of the section,which is favorable to the occurrence and development of the structure.At the same time,the tectonic activity further enhances the strength of the fluid activity,thus promoting the occurrence of tectonic reversal.This cohesive relationship between tectonics and fluid is essential for the transport of oil and gas.