Quadrangle-grid velocity-stress finite-difference method for elastic-wave-propagation simulation

• Published in: Geophysical journal international Vol. 131; no. 1; pp. 127 - 134
• Main Author: Jianfeng, Zhang
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.10.1997
• Subjects: elastic-wave theory; seismic modelling; topography
• ISSN: 0956-540X; 1365-246X; 1365-246X
• DOI: 10.1111/j.1365-246X.1997.tb00599.x

I present a 2-D numerical-modelling algorithm based on a first-order velocity-stress hyperbolic system and a non-rectangular-grid finite-difference operator. In this method the velocity and stress are defined at different nodes for a staggered grid. The scheme uses non-orthogonal grids, thereby surface topography and curved interfaces can be easily modelled in the seismic-wave-propagation stimulation. The free-surface conditions of complex geometry are achieved by using integral equilibrium equations on the surface, and the stability of the free-surface conditions is improved by introducing local filter modification. The method incorporates desirable qualities of the finite-element method and the staggered-grid finite-difference scheme, which is of high accuracy and low computational cost.