Data-driven control over short-period internal multiples in media with a horizontally layered overburden
Abstract
Short-period internal multiples, resulting from closely spaced interfaces, may interfere with their generating (bandlimited) primaries, and hence they pose a long-standing challenge in their prediction and removal. A recently proposed method based on the Marchenko equation enables removal of the entire overburden-related scattering by means of calculating an inverse transmission response. However, the method relies on time windowing and can thus be inexact in the presence of short-period internal scattering. In this work, we present a detailed analysis of the impact of band-limitation on the Marchenko method. We show the influence of an incorrect first guess, and that adding multidimensional energy conservation and a minimum phase principle may be used to correctly account for both long- and short-period internal multiple scattering. The proposed method can currently only be solved for media with a laterally invariant overburden, since a multidimensional minimum phase condition is not well understood for truly 2-D and 3-D media. We demonstrate the virtue of the proposed scheme with a complex acoustic numerical model that is based on sonic log measurements in the Middle East. The results suggest not only that the conventional scheme can be robust in this setting, but that the ‘augmented’ Marchenko method is superior, as the latter produces a structural image identical to one where the finely layered overburden is missing. This is the first demonstration of a data-driven method to account for short-period internal multiples beyond 1-D. Show more
Permanent link
https://doi.org/10.3929/ethz-b-000407076Publication status
publishedExternal links
Journal / series
Geophysical Journal InternationalVolume
Pages / Article No.
Publisher
Oxford University PressOrganisational unit
03953 - Robertsson, Johan / Robertsson, Johan
Funding
641943 - Waves and Wave-Based Imaging in Virtual and Experimental Environments (SBFI)
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