利用横纵波时差比值评价致密性储层裂缝的方法  

Fracture Evaluation of Tight Reservoir Using The Ratio of Shear Slowness to Compressional Slowness

作　　者：张志存[1] 王佳平[1] 王淑贤[1] 

机构地区：[1]大庆钻探工程公司测井公司,黑龙江大庆163412

出　　处：《测井技术》2008年第2期155-158,共4页Well Logging Technology

摘　　要：通过对声波在岩石中传播特性的分析发现,致密性储层的横波和纵波时差都随着储层孔隙度的增大而增大,在一定孔隙度区间内横纵波时差比值基本不变;但当致密性储层中发育裂缝时,其横波时差有明显增大,而纵波时差变化不明显。横纵波时差比值越大,说明致密性储层裂缝发育程度越高。应用发现,利用横纵波时差比值评价储层裂缝的方法受到地层岩性变化、声波传播路径与裂缝发育方向的关系和地层所含流体性质等多种因素的影响,应用中应结合其他识别和评价裂缝的方法综合评价。在大庆油田深层致密天然气储层中,利用横纵波时差比值评价储层裂缝取得了较好效果。The analysis of acoustic propagation properties in rocks shows that the shear slowness and the compressional slowness in tight zones increase with the increasing porosity of fractured reservoir, and the ratio of shear slowness to compressional slowness is unchanged within certain range of the porosities in fractured reservoir. Because of fractures developed in tight zones, shear slowness increases obviously, while compressional slowness doesn＇t change evidently. Therefore, the ratio of shear slowness to compressional slowness can be used to evaluate the fractures in tight zone, with which the method for evaluating fractured reservoir is affected by formation lithology changes, the relationship between the acoustic propagation path and the direction of fracture development and the peroperties of formation fluid and so on. The ratio of shear slowness to compressional slowness is another method of fracture identification and evaluation for sur-tight reservoir and it has been proved by the good application results in deep/tight gas reservoir with very low porosity and low permeability in Daqing oilfield.

关 键 词：测井解释 横纵波时差比值 致密性储层 裂缝 储层评价 

分 类 号：P631.84[天文地球—地质矿产勘探]