硬脆性页岩超声波透射实验研究

为了获取硬脆性页岩地层声波传播特征，以鄂尔多斯盆地井下石盒子组页岩为研究对象，采用超声波透射实验系统的分析了钻井液作用前后页岩声波时差、衰减系数、时域信号以及频域信号的特征。研究结果表明，钻井液作用后页岩声波时差增大，衰减系数增大，频域信号与时域信号均发生改变。钻井液作用后，页岩发生水化反应，声波时差与衰减系数可定量描述页岩水化动态变化，时域信号与频域信号能够定性分析页岩水化结构变化特征。超声波透射实验为硬脆性页岩水化特征的研究提供了一个新的思路。

Ultrasonic Transmission Experimental Study on Hard Brittle Shale

In order to acquire the law of acoustic propagation property of hard brittle shale formation, the shale of Shihezi formation in Ordos Basin are taken to be studied object, interval transit time, attenuation coefficient, time domain signal and frequency signal of hard brittle shale were sys-tematically analyzed before and after soaked on the drilling fluid used ultrasonic transmission experiment. The results showed that interval transit time and attenuation coefficient of shale in-crease, time domain signal and frequency signal change of shale after soaked on drilling fluid. Hydration occurs when shale is soaked on drilling fluid. interval transit time and attenuation co-efficient can quantificationally describe dynamically changes of hydration, time domain signal and frequency signal can qualitatively analyze changes of shale. ultrasonic transmission experiment offer a new idea for study the hydration characteristics of hard brittle shale.