Controlled Effect Of Strike-slip Fault On Carbonate Reservoir And Fluid Distribution In Tazhong ? Area

The formation of carbonate reservoirs and the distribution of fluids in the Tazhong II area of the Tarim Basin are controlled by strike-slip faults.The paper has a systematic dissection to the strike-slip faults.And it analyzed the evolution of the fracture,which include the classification of fractures,segmentation,stress state,and staging studies to analyze the evolution of fractures.Shows that after the Ordovician,Zhonggu 8 fracture exists two activities,the first one is in the late Sangta period,and the second is between the late Silurian to Devonian period.At the same time,Zhonggu 10 fracture exists two activities too,the first one is in the late Sangta period,and the second is between late silurian and early carboniferous.The strongest activity period of strike-slip faults are different,so it leads to different fluid filling.The larger the scale of the strike-slip fault,the more developed the reservoir is,which expressed as a big broken distance and a strong activity.The cracks and microcracks of the strike-slip fault are more developed,reservoirs are easily modified.And then combined with regional oil and gas filling period,think that the gas of Yanshan and Himalayan period was invaded from south to north.After the in-depth study of the stress characteristics of the fracture,it was found that late gas is difficult to invade from north to south that the fracture was under compressive stress.So it is not the later the fracture activity,the better the break open is.Perpendicular to the trend of fracture,near the fracture,oil and gas is filling strong,and away from the fracture,oil and gas filling weak.It is shown that far from the fracture,oil-water interface gradually uplift.And reach a certain distance,the oil and gas migrate along the unconformity surface,and controlled by inter-stratum karst,some well areas shown a uniform oil-water interface.