scholarly journals Numerical simulation of 2-D seismic wave propagation in the presence of a topographic fluid–solid interface at the sea bottom by the curvilinear grid finite-difference method

2017 ◽  
Vol 210 (3) ◽  
pp. 1721-1738 ◽  
Author(s):  
Yao-Chong Sun ◽  
Wei Zhang ◽  
Jian-Kuan Xu ◽  
Xiaofei Chen
Keyword(s):  
Numerical Simulation ◽  
Wave Propagation ◽  
Finite Difference ◽  
Finite Difference Method ◽  
Seismic Wave ◽  
Difference Method ◽  
Seismic Wave Propagation ◽  
Solid Interface ◽  
Sea Bottom ◽  
Curvilinear Grid

3D Seismic-Wave Modeling with a Topographic Fluid–Solid Interface at the Sea Bottom by the Curvilinear-Grid Finite-Difference Method

2021 ◽  
Author(s):  
Yao-Chong Sun ◽  
Wei Zhang ◽  
Hengxin Ren ◽  
Xueyang Bao ◽  
Jian-Kuan Xu ◽  
...  
Keyword(s):  
Wave Propagation ◽  
Finite Difference ◽  
Finite Difference Method ◽  
Particle Velocity ◽  
Grid Point ◽  
Interface Condition ◽  
Curvilinear Coordinates ◽  
Solid Interface ◽  
Sea Bottom ◽  
Curvilinear Grid

ABSTRACT The curvilinear-grid finite-difference method (FDM), which uses curvilinear coordinates to discretize the nonplanar interface geometry, is extended to simulate acoustic and seismic-wave propagation across the fluid–solid interface at the sea bottom. The coupled acoustic velocity-pressure and elastic velocity-stress formulation that governs wave propagation in seawater and solid earth is expressed in curvilinear coordinates. The formulation is solved on a collocated grid by alternative applications of forward and backward MacCormack finite difference within a fourth-order Runge–Kutta temporal integral scheme. The shape of a fluid–solid interface is discretized by a curvilinear grid to enable a good fit with the topographic interface. This good fit can obtain a higher numerical accuracy than the staircase approximation in the conventional FDM. The challenge is to correctly implement the fluid–solid interface condition, which involves the continuity of tractions and the normal component of the particle velocity, and the discontinuity (slipping) of the tangent component of the particle velocity. The fluid–solid interface condition is derived for curvilinear coordinates and explicitly implemented by a domain-decomposition technique, which splits a grid point on the fluid–solid interface into one grid point for the fluid wavefield and another one for the solid wavefield. Although the conventional FDM that uses effective media parameters near the fluid–solid interface to implicitly approach the boundary condition conflicts with the fluid–solid interface condition. We verify the curvilinear-grid FDM by conducting numerical simulations on several different models and compare the proposed numerical solutions with independent solutions that are calculated by the Luco-Apsel-Chen generalized reflection/transmission method and spectral-element method. Besides, the effects of a nonplanar fluid–solid interface and fluid layer on wavefield propagation are also investigated in a realistic seafloor bottom model. The proposed algorithm is a promising tool for wavefield propagation in heterogeneous media with a nonplanar fluid–solid interface.

Modeling seismic wave propagation in a coal-bearing porous medium by a staggered-grid finite difference method

2011 ◽  
Vol 21 (5) ◽  
pp. 727-731 ◽  
Author(s):  
Guangui Zou ◽  
Suping Peng ◽  
Caiyun Yin ◽  
Xiaojuan Deng ◽  
Fengying Chen ◽  
...  
Keyword(s):  
Porous Medium ◽  
Wave Propagation ◽  
Finite Difference ◽  
Finite Difference Method ◽  
Seismic Wave ◽  
Difference Method ◽  
Seismic Wave Propagation ◽  
Staggered Grid

An improved immersed boundary finite-difference method for seismic wave propagation modeling with arbitrary surface topography

Geophysics ◽  
2016 ◽  
Vol 81 (6) ◽  
pp. T311-T322 ◽  
Author(s):  
Wenyi Hu
Keyword(s):  
Wave Propagation ◽  
Free Surface ◽  
Finite Difference ◽  
Finite Difference Method ◽  
Surface Topography ◽  
Seismic Wave ◽  
Difference Method ◽  
Forward Modeling ◽  
Seismic Wave Propagation ◽  
Immersed Boundary

To accurately simulate seismic wave propagation for the purpose of developing modern land data processing tools, especially full-waveform inversion (FWI), we have developed an efficient high-order finite-difference forward-modeling algorithm with the capability of handling arbitrarily shaped free-surface topography. Unlike most existing forward-modeling algorithms using curvilinear grids to fit irregular surface topography, this finite-difference algorithm, based on an improved immersed boundary method, uses a regular Cartesian grid system without suffering from staircasing error, which is inevitable in a conventional finite-difference method. In this improved immersed boundary finite-difference (IBFD) algorithm, arbitrarily curved surface topography is accounted for by imposing the free-surface boundary conditions at exact boundary locations instead of using body-conforming grids or refined grids near the boundaries, thus greatly reducing the complexity of its preprocessing procedures and the computational cost. Furthermore, local continuity, large curvatures, and subgrid curvatures are represented precisely through the employment of the so-called dual-coordinate system — a local cylindrical and a global Cartesian coordinate. To properly describe the wave behaviors near complex free-surface boundaries (e.g., overhanging structures and thin plates, or other fine geometry features), the wavefields in a ghost zone required for the boundary condition enforcement are reconstructed accurately by introducing a special recursive interpolation technique into the algorithm, which substantially simplifies the boundary treatment procedures and further improves the numerical performance of the algorithm, as demonstrated by the numerical experiments. Numerical examples revealed the performance of the IBFD method in comparison with a conventional finite-difference method.

A High-Order Finite-Difference Method on Staggered Curvilinear Grids for Seismic Wave Propagation Applications with Topography

2021 ◽  
Author(s):  
Ossian O’Reilly ◽  
Te-Yang Yeh ◽  
Kim B. Olsen ◽  
Zhifeng Hu ◽  
Alex Breuer ◽  
...  
Keyword(s):  
Wave Propagation ◽  
Finite Difference ◽  
Finite Difference Method ◽  
Difference Method ◽  
Vertical Axis ◽  
Cartesian Grid ◽  
Staggered Grid ◽  
Graphic Processing Units ◽  
Curvilinear Grids ◽  
Curvilinear Grid

ABSTRACT We developed a 3D elastic wave propagation solver that supports topography using staggered curvilinear grids. Our method achieves comparable accuracy to the classical fourth-order staggered grid velocity–stress finite-difference method on a Cartesian grid. We show that the method is provably stable using summation-by-parts operators and weakly imposed boundary conditions via penalty terms. The maximum stable timestep obeys a relationship that depends on the topography-induced grid stretching along the vertical axis. The solutions from the approach are in excellent agreement with verified results for a Gaussian-shaped hill and for a complex topographic model. Compared with a Cartesian grid, the curvilinear grid adds negligible memory requirements, but requires longer simulation times due to smaller timesteps for complex topography. The code shows 94% weak scaling efficiency up to 1014 graphic processing units.

Sign in / Sign up

Export Citation Format

Share Document