Abstract:This paper deal with the control effect of normal drag structure generated by contemporaneous reverse fault on high frequency sequence strata structure and its depositional fillings. It is unique and novel to use secondary structural elements, namely, normal drag structure generated by contemporaneous reverse fault to reveal the coupling relationship between structure and deposition. Based on analysis of core, logging and seismic data, the fault elements of contemporaneous reverse fault in the study area are analyzed through geological analysis, structure balanced section technology and well to seismic calibration, etc. Then the characteristics of normal drag structure and its control mechanism on high frequency sequence structure and distribution of sand body are put forward. The results show that normal drag structure has three characteristics, including the formation of curved anticlines in local uplift of hanging wall, approximately nonsymmetrical normal faults beams caused by stress inversion along the core of anticline and low level development of sand body. High frequency sequence structure is obviously controlled by normal drag structure resulted from contemporaneous reverse fault. The footwall strata thickness is much thicker than that of the upper plate and hanging wall is subjected to erosion due to the strong uplift effect. As a result, the bottom—up formation gradually increases its erosional scale, leading to differential erosion; and “thick—thin—thick” distribution pattern of the formation forms vertically to the fracture direction. At the same time, the local unconformity interface formed by formation erosion is the key boundary for sequence stratigraphy study, which also providing a basis for establishment of the isochronous stratigraphic framework. Differential uplift depositional bed form formed by normal drag structure controls the direction of ancient flow system, so it determines the dispersion of sand body and filling pattern. The development of sand body is low in uplift anticline area, which is vertical to contemporaneous reverse fault direction. Most of the uplift anticline area is non main reservoir mainly with sand mud interaction and thick mud intercalated by thin layers of sand. On the contrary, the development of main reservoir sand body formed in the asymmetric anticline wings of the normal drag structure development is much higher.