裂缝诱导双相HTI介质模型及其弹性波传播方程

Fracture-induced two-phase HTI medium model and its elastic wave propagation equations

将Biot双相介质理论与Gurevich裂缝各向异性理论相结合,建立了能够同时考虑实际裂缝性储层孔隙性和各向异性的裂缝诱导双相HTI介质模型。从本构方程、动力学方程和动力学达西定律出发,推导出了裂缝诱导双相HTI介质中弹性波传播的一阶速度-应力方程,并针对方程的刚性问题,给出了利用显式二阶时间积分法数值求解该方程时所需要满足的稳定性条件。该方程能够定量地给出双相HTI介质的波场特征与裂缝参数、背景孔隙介质参数之间的关系,描述弹性波在这种介质中的传播机理。

Fracture-induced two-phase horizontal transverse isotropic （HTI） medium model has been established by combining Biot two-phase media theory with Gurevich fracture anisotropic theory,which can consider porosity and anisotropy of realistic fractured reservoir simultaneously.According to the constitutive equations,the dynamical equations and the dynamic Darcy＇s law,one-order velocity-stress elastic wave propagation equation has been derived.As to the stiffness problems of the equation,the stability condition is given when the equations are solved numerically by second-order explicit time integration algorithm.The equation can quantitatively present the relationships between the characteristics of wave field with fracture parameters and the parameters of background poroelastic media,and reveals the mechanisms of seismic wave propagation in this media.