Research On Structural Styles In Bian-Min-Yang Region

Bian-Min-Yang(B-M-Y) region, located in the southeast of Jinhu depression, the west of the Dongtai Sag, of the Subei Basin. In this thesis, based on the status of stratum, explaining and analyzing many pieces of seismic cross section plane, and getting structural styles and structural pattern of working area. Then basing on the structural styles, using balanced section technique, studying on tectonic evolution history of the selective seismic cross section, open out fault formation and evolution of each structural activity stage, at the same time analyze fault activity characteristics. Moreover discuss the control functions of fault activity to pool-forming, as well as instruct the structural explanation and the law of pool-forming, which has the practical significance of forecasting hydrocarbon trap and instructing petroleum exploration and development. The research results show that the west of work area is the structural main zone, which has few faults. The east area has many faults and the structure is more complex. The profile morphology of normal fault includes non-rotation plane type, rotation plane type and shovel-like type. And the main profile composite patterns are"Y"font, graben, stepladder. In the plane, the combination type of fault is parallel-aligned, grid-type, broom-like, skew-type. For the first time, analyze systematically structural evolution process by using balanced section technique, get the result is, the intensity of structural activity was alternative, the fault activity was obvious differences, the transference phenomenon of structure was existing, vertical movement was differential. Combining structural evolution, fault movement cycle, the result of fault growth index and fault ancient fall, concretely analyze the differences of fault activity vertically and flatly. Most of faults were formed in the early stage of Wubao Movement, and developing in Funing Formation. The position of intense activity in all Funing Formation was migrated continuously on the plane, getting from south to north. At last, simply analyze the control functions of fault activity to pool-forming. The result of study indicates: fault activity control the evolution of source rock, main trap type should belong to fault nose, faults are the main channels of vertical migration of oil and gas ; fault activity controls the vertical and plane distribution of oil and gas.