Wave-Equation Migration from Topography

Wave-equation migration from topography usually involves additional processing to regularize the acquired seismic data. However, these issues can also be addressed using the converse strategy of adapting wave-equation migration algorithms to be conformal with acquisition geometry. In this paper, the latter approach is examined through the development a methodology for imaging directly from acquisition coordinates. After generating acquisition coordinate systems using a conformal mapping approach, wavefields are extratpolated on these computational meshes using Riemanninan wavefield extrapolation. This imaging strategy is tested on a 2D field dataset acquired in the Canadian Rocky Mountain Foothills. After detailing the initial data processing, I present the results of a wave-equation migration from topography test. The test results indicate that the approach generates good images, especially in the near-surface. Comparisions with Kirchhoff migration results from a flat datum indicate that the wave-equation migration from topography images are superior. However, further benchmark tests are required before definitive statements about the relative merits of the wave-equation from topography approach can be reached.