Reciprocity of tensor wavefields
نویسنده
چکیده
If reciprocity principles are invoked in seismic data processing algorithms, one has to make sure that those processes maintain reciprocity. I outline briefly the derivation of reciprocity principles for elastic wave equations and show that discretized or approximated wave equations can lose symmetry properties and thus reciprocities. This effect is important if one is concernd about true-amplitude processes and if one needs to use reciprocity arguments. I show an example of an elastic finite-difference approximation to the wave equation that is not reciprocal, but can be made reciprocal by symmetrizing the Green’s function kernel properly.
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