流体性质对岩石地震波速度的影响

地震响应的变化源于地下地层结构和岩石弹性性质的变化。对岩石弹性性质的影响因素很多,也很复杂,主要有压力、温度、孔隙度及孔隙形态、流体类型及其饱和度等。根据Biot-Gassmann和Kuster-Toksz理论模型,分析了不同孔隙度下流体性质及其饱和度对岩石弹性性质的影响,讨论了两种理论模型计算结果的差异。认为流体对岩石地震波速度的影响主要与孔隙度大小和孔隙形状有关,纵波阻抗对储层中流体变化最敏感,横波阻抗对流体变化不敏感,通过纵横波阻抗联合应用可以提高对储层流体变化的识别精度。

The impact of the fluid properties on the seismic wave velocities in rocks

A variety of seismic responses result from the varieties of strata constitution and rock elastic properties underground. The rock elastic properties are affected by many factors, such as pressure, temperature, porosity/porous shape, fluid type and saturation, etc. According to the tow theoretical models Biot-Gassmann and Kuster-Toksoz, the impacts of the fluid properties in different porosities and saturations on the rock elastic properties, and the computations from the tow models were analyzed. The results are that the impacts of the fluid on the seismic velocities are mainly relevant to the porosity sizes and the porous shapes, P wave impedance is sensitive to the variety of the fluid in reservoir, on the contrary, the S wave is not, so the identification precision on the fluid varieties in reservoir can be improved by the joint application of the S wave and P wave.