摘要
从基于Biot理论建立的双相各向异性弹性波方程出发,推导出二维双相PTL介质弹性波方程。在此基础上,高阶实现了高阶有限差分数值模拟,并对双相PTL介质模型和实际测井数据模型进行模拟试算。基于模拟结果,分析了各类波的传播规律,讨论了弹性参数和耗散系数对地震波传播的影响。结果表明:在双相PTL介质中存在快纵波、慢纵波和SV波,并具有各向异性,两种纵波有明显的区别,快纵波的速度远大于慢纵波的速度;慢纵波具有很强的衰减性,能否观察到慢纵波是与含流体地层介质的耗散性质有关。
Elastic wave equations in a fluid-saturated porous solid of periodic thin layer(PTL)anisotropy are derived from the elastic wave equations in two-phase anisotropic media established on the Biot Theory.On the basis of this,a numerical stimulation of high order finite difference was realized and a trial calculation was done on the model in a fluid-saturated porous solid of periodic thin layer(PTL)anisotropy and on the model with actual logging data.The propagation laws of all kinds of waves were analyzed and the influence of elastic parameters and dissipation coefficient on seismic wave propagation was discussed based on the stimulation result,which shows that ①there is anisotropic fast and slow P-waves and SV wave in a fluid-saturated porous solid of periodic thin layer(PTL)anisotropy;②the speed of the fast P-wave is much higher than that of the slow P-wave;③due to the strong attenuation of the slow P-wave,whether the slow P-wave can be observed or not depends on the dissipative property of the formation with fluids.
引文
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