Fault System And Lateral Seal Of Faults Of Qijia-Yuanyanggou In West Sag, Liaohe Depression

By thoroughly analyze the geometry features of faults on the basis of 3D seismic data interpretation of Qijia-Yuanyanggou area, based on deformation style and strength in the vertical structure divided into three Structural layer(not including the basement): the fault-sinking, fault-saging and depressing. Among them, The fault-sinking structural layer as the boundary is divided into upper and lower sets of the fault system, communicated by long-term active fault. General fault strike is NEE-NE and the fault scale decreased from fault-sinking structural layer to depressing structural layer.The three phases of evolution of faults in Qijia-Yuanyanggou area are phase of stretching deformation during the early stages from the fourth member of sha to the third member of sha, strike-slip extensional deformation during the interim period from the first member of sha to Dongying and Late transtensional deformation stage after Guantao. On this basis, divided into six sets of fault systems, that early extensional, middle extending strike-slip, late transtensional, early extensional-middle extending strike-slip, middle extending strike-slip-late transtensional and early extensional-middle extending strike-slip -late transtensional fault systemBy anatomy of typical traps and statisticing the sand and shale thickness on both sides of control reservoir fault, it shows that the main types of lateral seal are fault rocks, and only individual traps are type sand-shale Juxtaposition type. On the basis of structural properties of the fault and section closed property analysis, It has established lateral seal evaluation system of Shahejie reservoirs by oil-water interface calibration of typical drilled fault-traps. and predicted the lateral sealing ability of fault-traps in the reservoirs. characteristics of fault activities after accumulation indicate that the lateral sealing of faults is destructive.The match relationship between fault systems and reservoir accumulation indecated that early extensional, middle extending strike-slip fault system play the role of the major block, late transtensional, middle extending strike-slip-late transtensional fault system mainly paly the role of destruction- adjustment, early extensional-middle extending strike-slip, early extensional-middle extending strike-slip -late transtensional fault system paly the role of oil-source faults.The relationship between fault activity patterns and distribution of Oil and gas showed that the faults on hydrocarbon accumulation in control of the main aspects of the role of three: oil-source faults control parts of oil and gas accumulation; lateral sealing of faults control the filling of hydrocarbon in traps; intensity of fault movement control oil and gas conservation and loss.The above results established the fault-controlling-reservoir mode of Qijia-Yuanyanggou area, And confirmed the favorable sedimentary facies and oil-source region when the full entent in fault-trap is more than 50% and the faulting rate is more than 2m/Ma, the drilling risk minimization, is the next favorable target areas.