The influence of structural characteristics on the preservation conditions of shale gas in Nanchuan area, Chongqing

Starting from the structural characteristics of the Nanchuan block in the transition zone of the southeast basin margin of Chongqing, in-depth analysis of the layered differential structural characteristics, regional differential structural characteristics, and structural evolution characteristics, so as to clarify the influence of different structural characteristics on shale gas preservation conditions in the Nanchuan area.The research results show that, ①The Nanchuan area is divided into four detachment strata in the vertical direction, creating four deformation layers in the vertical direction.②The structural force in the Nanchuan area is gradually weakened from east to west in the horizontal direction, changing from thrust characteristics.It is a fracture feature, and finally becomes a slip feature.③The main structural features of Nanchuan area were formed in the Middle Yanshanian and Late Yanshanian.④The overall preservation conditions of the thrust structure belt in Nanchuan area are poor, which is not conducive to the exploration and development of shale gas; the fault extension structure belt has good preservation conditions and is a favorable area for shale gas exploration and development.The detachment structural belt has good overall preservation conditions, but due to the deep shale formation, it is a favorable target area for shale gas exploration in the next step.