CHARACTERISTICS OF STRUCTURAL SLOPE-BREAK ZONE AND ITS CONTROLLING EFFECT ON SEDIMENT IN THE QIONGDONGNAN BASIN

Structural slopebreak zones, which are produced by the longterm activities of syndepositional faults, have always been an important factor of the depositional sequence development and the deposition process. Based on the concept of the structural slopebreak, this paper focuses on the distribution characteristics of the sedimentary system and conduit framework. Four types of syndepositional fault slopebreak patterns are identified, which are comblike structure, broomlike structure, forklike structure and reversing Tshaped structure. Furthermore, the relationship between the slopebreaks and the distribution patterns of the sand bodies in the Qiongdongnan basin is discussed. At the same time,the differences of their migration ability are studied simply.This paper also describes the characteristics of structural slopebreak zone in detail.It's no doubt that the structural slopebreak always controls the development of the conduit system, the position of rolling anticline is favorable for petroleum accumulation, and the superposition area of the structural slopebreak zone and the pressure transition zone is very important for exploration in the Qiongdongnan basin.