Rigorous redatuming

Marchenko redatuming below a complex overburden

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 over...

Internal multiple suppression by adaptive Marchenko redatuming

Recently, a novel iterative scheme was proposed to retrieve Green’s functions in an unknown medium from its single-sided reflection response and an estimate of the propagation velocity. In Marchenko imaging, these Green’s functions are used for seismic imaging with complete wavefields, including internal multiple reflections. In this way, common artifacts from these internal reflections are avo...

Model-based redatuming of seismic data: An inverse-filter approach

Standard model-based redatuming techniques consist in applying time shifts to the surface data, to simulate an acquisition made at depth. The time shifts are computed using prior knowledge of the overburden, such as a macro velocity model. These techniques allow focusing of the direct waves at the new datum, but the focus can be degraded because of surface multiples and internal multiples in th...

Rigorous Convex

In order to generate valid convex lower bounding problems for noncon-vex twice{diierentiable optimization problems, a method that is based on second{ order information of general twice{diierentiable functions is presented. Using interval Hessian matrices, valid lower bounds on the eigenvalues of such functions are obtained and used in constructing convex underestimators. By solving several non-...

Systematic reviews: the case for rigorous methods and rigorous reporting.