柱面分层流体饱和孔隙地层中的声波测井波场模拟  

Simulation of acoustic well-logging wave field in a radially multilayered fluid-saturated porous formation

作　　者：李巍[1,2] 胡恒山[1,2] 张碧星[3] 刚铁[2] 

机构地区：[1]哈尔滨工业大学航天科学与力学系,哈尔滨150001 [2]现代焊接生产技术国家重点实验室,哈尔滨150001 [3]中国科学院声学研究所声场声信息国家重点实验室,北京100190

出　　处：《声学学报》2010年第4期455-464,共10页Acta Acustica

基　　金：国家自然科学基金项目(40874062);现代焊接生产技术国家重点实验室基金

摘　　要：因钻井作业时泥浆侵入等因素,井外介质沿径向常呈现非均匀性。本文将地层视为柱面分层孔隙介质,采用传递矩阵法模拟声波测井波场。注意到慢纵波波数的实部和虚部都很大,当井外含大厚度层且频率较高时,易因计算大自变量的Hankel函数而溢出,我们在波场表达式中引入了归一化的Hankel函数。论文将前人模拟关于柱面分层固体弹性介质声波测井的广义反射/透射系数计算方法推广到了分层孔隙介质情况,导出了波幅系数的计算公式,并针对含侵入带的柱面分层孔隙地层,计算了声波测井全波波形。The formation out of a borehole is usually radially inhomogeneous due to mud invasion caused by drilling operations.In this study it is assumed that the formation consists of radially multilayered porous layers,and a transfer matrix method is adopted to simulate acoustic well-logging waveforms.It is noticed that the real and imaginary parts of slow compressional wave number are both very large when there is a thick annulus layer out of the borehole at a high frequency,so that the Hankel function is prone to overflow with large arguments.To solve this problem,normalized Hankel functions are introduced to the wave field expressions.The generalized reflection and transmission coefficient method is extended to calculate the wave field in radially multilayered porous formations.Recursive formulae for wave amplitude coefficients are deduced.As an example,acoustic full waveforms are calculated to simulate logging responses in a radially multilayered porous formation with an invaded zone.

关 键 词：波场模拟 声波测井 孔隙地层 柱面 流体饱和 Hankel函数 孔隙介质 传递矩阵法 

分 类 号：P631.814[天文地球—地质矿产勘探]