3-D finite-difference elastic wave modeling including surface topography
3-D finite-difference elastic wave modeling including surface topography
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DOI：
10.1190/1.1444360
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发表时间：
1998-04
期刊：
影响因子：
3.3
通讯作者：
S. Hestholm;B. Ruud
中科院分区：
文献类型：
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作者：
S. Hestholm;B. Ruud
已经进行了自由表面地形地震散射的三维有限差分（FD）模拟。我们已经开发出精确的三维自由表面地形边界条件的颗粒速度。在交错网格上采用八阶FD方法对完整弹性波方程的速度-应力公式以及边界条件进行了数值模拟。我们给出了一个将边界条件与弯曲网格波动方程相结合的数值稳定性准则，其中弯曲网格表示具有地形的物理介质。该稳定性标准的实施阻止了在陡峭和粗糙地形区域中出现的不稳定性。我们已经模拟了从一个平面，垂直入射波阵面和真实的地形从一个40 × 40公里的地区集中在挪威东南部的NORESS阵列的地震接收站的地震P波的散射。波场的合成快照和地震记录显示出从P波到Rg（sh）波的明显转换。
Three‐dimensional finite‐difference (FD) modeling of seismic scattering from free surface topography has been pursued. We have developed exact 3-D free surface topography boundary conditions for the particle velocities. A velocity‐stress formulation of the full elastic wave equations together with the boundary conditions has been numerically modeled by an eighth‐order FD method on a staggered grid. We give a numerical stability criterion for combining the boundary conditions with curved‐grid wave equations, where a curved grid represents the physical medium with topography. Implementation of this stability criterion stops instabilities from arising in areas of steep and rough topographies. We have simulated scattering from teleseismic P-waves using a plane, vertically incident wavefront and real topography from a 40 × 40 km area centered at the NORESS array of seismic receiver stations in southeastern Norway. Synthetic snapshots and seismograms of the wavefield show clear conversion from P-waves to Rg (sh...