本文定义了各向异性黏弹性参数修正因子,并将其引入到黏弹性模型中以体现泥质含量对黏弹性机制的影响,同时将波传播过程中孔隙介质骨架黏弹性力学机制与两种孔隙流体流动力学机制(Biot流动和喷射流动机制)有机地统一起来处理,从而给出了描述含泥质低孔渗孔隙各向异性介质中波传播规律的黏弹性Biot/squirt(BISQ)模型.数值计算结果表明,入射波的方位角、各向异性渗透率以及泥质含量等对含流体复杂孔隙介质中波频散和衰减的影响具有显著的方位各向异性特征,在低频范围内(地震波勘探频率)黏弹性力学机制对波传播能量的衰减起主导作用.
In order to describe the effect of the clay content on the viscoelastic mechanism, a correction factor of anisotropic viscoelastic parameters was defined and introduced into our viscoelastic model. At the same time, viscoelastic mechanism and two flow mechanisms of pore fluids (Biot-flow and squirt-flow mechanism) were simultaneously included in a united viscoelastic Biot/squirt (BISQ) model which describes the wave propagating in the porous viscoelastic anisotropic media with the low permeability/porosity and bearing with clay. Numerical results show that the effects of angle of wave propagation, anisotropic permeability and the clay content on wave dispersion and attenuation are obviously anisotropic for wave propagating in complex porous media saturated with fluids. The viscoelastic mechanism is mainly responsible for energy loss of wave propagation in low frequency range (seismic exploration).