Marchenko redatuming below a complex overburden
نویسندگان
چکیده
Complex overburdens can severely distort transmitted wavefields, posing serious challenges for seismic imaging. In Marchenko redatuming, we use an iterative scheme to estimate so-called focusing functions, which can be used to redatum seismic wavefields to a specified level below the major complexities in the subsurface. Unlike in conventional redatuming methods, internal scattering in the overburden is accounted for by this methodology. Through Marchenko redatuming, internal multiple reflections are effectively utilized and common artefacts that are caused by these multiples are suppressed. The redatumed data can be interpreted as if it were acquired at the redatuming level and as if the medium above this level were non-reflecting. We provide an interpretation of the iterative scheme that is used for Marchenko redatuming and we evaluate its performance in a medium with a strongly heterogeneous overburden.
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