| Based on the full review of previous data,this thesis divides the fault zone into sandmudstone interlayer fault zone(Vsh<40%)and mudstone fault zone(Vsh>40%)based on the shale content based on core data,logging data and thin-sheet data,the structural characteristics and deformation mechanism of sand-mudstone interlayer fault zone and mudstone fault zone are discussed respectively,and the sand-mudstone interlayer fault zone evolution model and mudstone fault zone evolution model are established.Based on the principle of similarity the simulation experiments of fault conductance under different structures are reproduced,and the relationship between the structure of fault zone and hydrocarbon accumulation is discussed in detail.Studies have shown that although the extensional fault zone has a dual structure: fault core and fracture zone,there are differences in the structure of the fault zone in different lithologies.In the sand-mudstone interlayer fault zone,the fault core mainly develops fault breccia and tectonic lens bodies,and the upper and lower disk fracture zones mainly develop induced fractures,which are large in scale.In the mudstone fault zone,the fault core mainly develops mudstone smearing and fault Mud,small cracks developed in the upper and lower plate fracture zone,and the scale is small.The sandmudstone interlayer fault zone evolves from a monolithic structure with only sliding surfaces to discontinuous fault cores to a binary structure.Its deformation mechanism is particle rolling and rupture mechanism.The evolution mode of the mudstone fault zone is also from the deformation mechanism of unary structure to incomplete binary structure and then to complete binary structure is mainly drag deformation and smear.In the sandmudstone interlayer fault zone,the oil and gas migration mode is mainly vertical transport.In the mudstone fault zone,the oil and gas migration mode is mainly lateral diversion.Figure 30;Table 6;Reference 56... |
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