Structural Deformation And Hydrocarbon Enrichment In The Central And Southern Part Of Wen'an Slope

The Wen'an Slope is located in the eastern part of the Baxian Sag,and the whole NNE is distributed.As a gentle slope of the braided fault depression,the whole structure has the characteristics of eastward and westward tilting.The Paleogene stratum is fully developed and is superimposed from west to east.Wen'an Slope is one of the oil and gas enrichment belts in Baxian Depression.The sedimentary lithology is variable and the structure is complex.Although the degree of exploration is relatively high,the structural deformation characteristics,tectonic evolution process,reservoir control mechanism and hydrocarbon accumulation model of the slope area have not been systematically studied.Based on the theory of modern tectonic geology,the thesis applies seismic interpretation,structural analysis,equilibrium profile,stratigraphic correlation,and comprehensive study of hydrocarbon accumulation and reservoirs to comprehensively analyze the structural characteristics and accumulation conditions of the Wen'an slope:1.The study area is located in the south of the Taishan fault on the slope,and mainly develops NNE,NE and NW strikes.It can be divided into four tectonic units by fracture division.From north to south,it is Suqiao South nose-like tectonic belt,Shigezhuang nose-like tectonic belt,Changfeng town nose-like tectonic belt and Yilunbao nose-like tectonic belt.2.The Wen'an slope mainly develops the extensional structure of the forward tilting block,the reverse tilting block,the base combination,the"y"shape and the anti"y"shape,and the negative flower structure is developed in the local area.3.The slope evolution experienced four periods of intense rotation,basal adjustment,overall slow sloping and overall settlement.4.The Wen'an slope mainly develops a delta sedimentary system.In the central and southern parts of the Wen'an slope,controlled by tectonic movement and sedimentation,the oil and gas enrichment horizon is mainly from the Es₃ to Ed formation.5.The Baxian Gully,the Luzhou Gully and the Maxi Gully provide oil and gas for the central and southern parts of the slope.The fault acts as a hydrocarbon migration channel and converges in the nose-like structural zone to form a hydrocarbon accumulation model.