套管井中超声反射波频谱分析  

Analysis of Spectra of Reflected Ultrasonic Waves in Cased Holes

作　　者：周继宏[1] 

机构地区：[1]江汉石油学院地球物理勘探系

出　　处：《江汉石油学院学报》1999年第1期33-36,共4页Journal of Jianghan Petroleum Institute

摘　　要：在考虑介质对超声波吸收的前提下，对３种典型地层（灰岩、砂岩和泥岩）套管井中超声反射波频谱在４种水泥胶结（完全胶结、自由套管、套管与水泥层胶结差及水泥层与地层胶结差）和微环存在的情况下进行了数值计算。结果表明：反射波频谱主要受套管的厚度振动控制，并仅在包含套管厚度振动频率的一个频段内，受地层特性和水泥胶结类型的影响；只有在水泥胶结良好时，地层特性才对反射谱构成有意义的影响；水泥胶结类型不同，反射谱的特征亦不同；微环的存在相当于水泥环声阻抗变小。Assuming the acoustic absorption of media, the spectra of reflected ultrasonic waves in the cased holes drilled in 3 types of formations (limestone, sandstone and shale) with 4 modes of cement bonding (complete bonding, free pipe, bad bonding of casing with cement and of cement to the formation) and with fluid micro annulus are calculated, respectively The results show that the spectra are controlled by the casing's thickness vibration, and affected only by the formation and the cement bonding in a frequency band including the frequency of the casing's vibration through its thickness The spectra are affected by the formation characteristics only in the case of good cement bonding, and varied with the mode of cement bonding And the fluid micro annulus does not affect the shape of spectra, but its existence is equivalent to lowering the acoustic impedance of the cement

关 键 词：测井 套管井 超声波 反射波 频谱分析 声波测井 

分 类 号：P631.814[天文地球—地质矿产勘探]