Astronomy and Astrophysics – Astronomy
Scientific paper
Oct 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006geoji.167..337z&link_type=abstract
Geophysical Journal International, Volume 167, Issue 3, pp. 337-353.
Astronomy and Astrophysics
Astronomy
7
Finite Difference, Maccormack Scheme, Seismic Wave Simulation, Stress Image Method, Topography, Traction Image Method
Scientific paper
In this study, we propose a new numerical method, named as Traction Image method, to accurately and efficiently implement the traction-free boundary conditions in finite difference simulation in the presence of surface topography. In this algorithm, the computational domain is discretized by boundary-conforming grids, in which the irregular surface is transformed into a `flat' surface in computational space. Thus, the artefact of staircase approximation to arbitrarily irregular surface can be avoided. Such boundary-conforming gridding is equivalent to a curvilinear coordinate system, in which the first-order partial differential velocity-stress equations are numerically updated by an optimized high-order non-staggered finite difference scheme, that is, DRP/opt MacCormack scheme. To satisfy the free surface boundary conditions, we extend the Stress Image method for planar surface to Traction Image method for arbitrarily irregular surface by antisymmetrically setting the values of normal traction on the grid points above the free surface. This Traction Image method can be efficiently implemented. To validate this new method, we perform numerical tests to several complex models by comparing our results with those computed by other independent accurate methods. Although some of the testing examples have extremely sloped topography, all tested results show an excellent agreement between our results and those from the reference solutions, confirming the validity of our method for modelling seismic waves in the heterogeneous media with arbitrary shape topography. Numerical tests also demonstrate the efficiency of this method. We find about 10 grid points per shortest wavelength is enough to maintain the global accuracy of the simulation. Although the current study is for 2-D P-SV problem, it can be easily extended to 3-D problem.
Chen Xiaofei
Zhang Wanchuan
No associations
LandOfFree
Traction image method for irregular free surface boundaries in finite difference seismic wave simulation does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Traction image method for irregular free surface boundaries in finite difference seismic wave simulation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Traction image method for irregular free surface boundaries in finite difference seismic wave simulation will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-906002