柱面Love波频散分析与SH波场的数值计算(英文)  

DISPERSION ANALYSIS OF CYLINDRICAL LOVE WAVES AND NUMERICAL CALCULATION OF SH WAVES FIELD

作　　者：姚桂锦[1] 王克协[1] 马俊[1] 伍先运[1] 

机构地区：[1]吉林大学物理系,吉林长春130023

出　　处：《计算物理》2001年第1期37-42,共6页Chinese Journal of Computational Physics

基　　金：SupportedbytheNationalNaturalScienceFoundationofChina(496 742 2 6 )

摘　　要：对贴井壁环型剪切源在柱状双层弹性介质中激发的SH波场进行了理论求解 ,导出了柱面Love波频散方程 ,讨论了柱面Love波存在的条件及其区域 .通过数值计算考察了柱面Love波的频散特性和激发强度 ,发现最低阶柱面Love波具有截止频率 ,这与平面半空间双层弹性介质模型下的Love波无截止频率的特征不同 .渐近分析与数值考察都表明 ,井径r1→∞时 ,柱面Love波频散方程趋向平面双层半空间的Love波方程 ,柱面Love波的截止频率趋于零 .全波计算还显示用激发SH波来探测侵入带外原状地层的横波信息是一个十分简洁的途径 .SH wave field excited by circumferential shear source in cylindrically double layered media is theoretically analysed.Dispersion equation of cylindrical Love waves(guide waves)has been derived.Both existence condition and existence range of cylindrical Love waves are discussed.Dispersion and excitation of cylindrical Love waves are investigated by numerical calculation.It is discovered that the lowest order cylindrical Love waves have cut off frequency,which differs from Love waves in half space with horizontally double layered elastic media.The asymptotic expression of dispersion equation of cylindrical Love waves as well radius r 1→∞ consistently tends to the dispersion equation in the horizontal half space case,and cut off frequency tends to zero.The transient full waveform calculation is also calculated and illustrated, showing that realizing direct shear wave logs through exciting SH wave would be a more forthright way. [

关 键 词：声波测井 柱面LOVE波 频散方程 SH波场 横波速度 数值计算 

分 类 号：P631.84[天文地球—地质矿产勘探]