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选择４种地壳岩石样品，经干燥或水饱和处理后在不同围压条件下测量了在其中传播的纵、横波的速度及其各向异性．在大气压条件下低孔隙度（＜１％岩样中，水饱和样品中的纵波速度明显地比干燥样品中的高，但横波速度的差别不大．因为在低孔隙度岩样中纵波速度对孔隙流体的反应比横波速度敏感，可以用泊松比的变化来反映随着围压的增加晶粒间流体对弹性波传播特性的影响．根据实验数据，按Ｏ’Ｃｏｎｎｅｌｌ模型分别计算了干燥和水饱和岩样中的裂纹密度，与通过实测体应变曲线得到的裂纹孔隙度十分吻合．利用横波的速度和偏振特性可以推断岩样中定向排列微裂纹的空间取向情况．研究表明，同时测量在岩样中传播的纵、横波的速度，通过Ｖｐ／Ｖｓ比值可以给出有关颗粒边界流体的证据，也可以估计岩样中的裂纹密度．
Four crustal rock samples were selected and the velocities and anisotropies of longitudinal and transverse waves propagating in the crust were measured under different confining pressures after drying or water saturation treatment. Low porosity at atmospheric pressure (<1% of the compressional wave velocity in water-saturated samples is significantly higher than in the dry samples, but the difference in shear-wave velocity is not significant because the compressional velocity in the low- The response of pore fluid is more sensitive than the shear wave velocity, and the variation of Poisson’s ratio can be used to reflect the effect of interfacial fluid on the elastic wave propagation characteristics with the increase of confining pressure.According to the experimental data, according to the O’Connell model, The crack density in water-saturated rock samples is in good agreement with the crack porosity obtained from the measured body strain curve. The spatial orientation of the aligned micro-cracks in rock samples can be inferred by using the velocity and polarization characteristics of shear waves. The velocities of longitudinal and shear waves propagating in the rock sample are shown by evidence of Vp / Vs ratios for the fluid at the grain boundaries and the crack density in the rock sample can also be estimated.