断裂封堵综合分析技术在孔雀河地区的应用

断裂在油气运移、聚集、成藏和保存过程中起着通道作用和封堵作用,通过该项研究可以分析受断裂控制圈闭的现今含油气性,进而为油气勘探的研究和部署提供更加翔实的科学依据。为此,利用地震地质综合信息识别断裂封堵性的3种技术方法——"断面物质涂抹法"、"断面应力分析法"和"断裂横向封堵系数法",对塔里木盆地孔雀河地区典型的开启性和封堵性断裂进行了研究,总结出研究区断裂在横向上和纵向上开启或者封堵的"临界值"分别为5 MPa、0.3 MPa,断裂横向封堵系数越大越有利于油气成藏,只有综合应用多项资料和方法,才能对断裂对油气的封堵性能做出更加合理的判定,发现同一断裂的封堵性随其所处地层时代、岩性和空间位置的不同而不同,探讨了研究区断裂在不同形成期次对各种圈闭的油气成藏控制作用。基于有井区的研究结果对无井地区的断裂进行了封堵性预测,为该区块的圈闭评价提供了依据。

Application of fault sealing integrated analysis technology to Kongquehe Area in NE Tarim Basin, Xinjiang, NW China

In the oil-gas migration,accumulation and reservation,faults may play two roles: channels or sealing.Through the research,we can analyze whether a fault-controlled trap bears oil-gas,thereby providing a solid scientific basis for oil-gas exploration.Three techniques,namely "impermeable interlayer method","stress analysis method" and "lateral sealing parameter method",could be used to evaluate the fault sealing ability for a fault-bounded oil-gas trap.These techniques have been applied to the Kongquehe region of NE Tarim Basin.The result shows that the "critical value" of the opening and sealing fault in vertical and lateral sense is 5 MPa and 0.3 MPa,respectively.A fault with a larger lateral sealing parameter is more favorable for oil-gas accumulation.Only by a synthetic application of a number of data and methods could we reasonably judge the fault sealing capability for oil-gas.It was found that the sealing ability for a single fault varies stratigraphically and/or lithologically.Faults are genetically classified into different groups;each group plays its specific role in the construction of an oil-gas trap.Based on research results from drilling wells,we predicted the fault sealing features of the non-drilling areas,providing a scientific basis for the trap-evaluation in these areas.