Abstract
In this article, the corresponding equations in curvilinear coordinate system based on the first-order velocity stress equation of two-phase isotropic media based on the improved BISQ model are derived, then the equations are numerically solved by an optimized high-order non-staggered finite difference scheme, that is, DRP/opt MacCormack scheme. To implement the undulating free-surface topography, we derive the analytical relationship between derivatives of velocity components and use the compact finite-difference scheme and traction-image method. The curvilinear grid finite difference method uses body-conforming grid to describe the free surface, thus avoids the numerical approximation caused by scattering. In the undulating free surface and the undulating interface of two-phase medium, the complex reflection wave and transmission wave can be clearly demonstrated by the numerical simulation results. The simulation results show that the curvilinear grid finite-difference method can accurately solve the propagation problem of seismic waves in a two-phase isotropic medium with undulating surface.
| Translated title of the contribution | Wavefield modeling in two-phase media including undulated topography based on reformulated BISQ model by Curvilinear Grid FD method |
|---|---|
| Original language | Chinese (Traditional) |
| Pages (from-to) | 3356-3373 |
| Number of pages | 18 |
| Journal | Acta Geophysica Sinica |
| Volume | 61 |
| Issue number | 8 |
| DOIs | |
| State | Published - 1 Aug 2018 |
Keywords
- Curvilinear grid
- Finite difference method
- Porous isotropic media
- Reformulated BISQ mechanism
- Undulating surface