[2011-06-02]


[2011-06-02]

Efficient One-way Wave-equation Migration in Tilted Transvesally Isotropic Medium

Cost-effective and accurate imaging tools for anisotropic media are becoming an integral part of the standard imaging workflow. While methods based on Reverse Time Migration (RTM) have great advantages over one-way methods in terms of handling multipathing, overturned reflections, internal multiples and arbitrary dips, one-way methods are still capable of delivering fit-for-purpose solutions at a fraction of the computational cost of RTM. We propose two different algorithms for depth extrapolation in Tilted Transversally Isotropic (TTI) media, using explicit and implicit finite differencing. Both approaches have advantages and can be combined in a highly efficient migration code. We demonstrate that the implicit methods presented in (Shan, 2009) can be generalised to handle dips close to 90 degrees at a modest increase in computational complexity, and propose a framework for generating and applying very short spatial explicit extrapolators with wavenumber-domain filters that successfully complement implicit methods to achieve a considerable migration speed-up.

Click on the thumbnail on the left to view the extended abstract of the paper presented at the 73rd Annual Conference of the European Association of Geophysicists and Engineers, held 23-26 May 2011 in Vienna.