水泥评价测井的数值研究

Numerical Study on the Cement Evaluation Well-Logging

通过数值计算,考查了水泥评价测井(CET)在各种水泥胶结情况下的反射波形及其频谱特征。结果表明,该测井方法能有效地克服微环影响,并提供对套管外水泥胶结质量的评价;对水泥与地层之间胶结情况的判断,仅利用波形时窗能量的比较是不够的,还应利用反射谱中吸收峰的变化特征;根据主吸收峰的频率可近似确定套管壁厚。

The character of several typical cement bounding condition is numerically studied, by which the reflecting waveform and spectral character have investigated. A cement evaluation tool can overcome the effects of microannulus and provide the cementing evaluation. In order to determine the cementing state between cement and formation, it is not enough to only analyze the reflecting energy in time windows, the characters of resonant peaks in the spectra must be used as well. The casing resonant frequency can be used to get roughly the thickness of steel case.