Internal multiple elimination: Can we trust an acoustic approximation?

Correct handling of strong elastic, internal, multiples remains a challenge for seismic imaging. Methods aimed at eliminating them are currently limited by monotonicity violations, a lack of a-priori knowledge about mode conversions, or unavailability of multi-component sources and receivers for not only particle velocities but also the traction...

Marchenko redatuming, imaging and multiple elimination, and their mutual relations

With the Marchenko method it is possible to retrieve Green's functions between virtual sources in the subsurface and receivers at the surface from reflection data at the surface and focusing functions. A macro model of the subsurface is needed to estimate the first arrival; the internal multiples are retrieved entirely from the reflection data....

Elastodynamic Marchenko method: advances and remaining challenges

Marchenko methods aim to remove all overburden-related internal multiples. The acoustic and elastodynamic formulations observe identical equations, but different physics. The elastodynamic case highlights that the Marchenko method only handles overburden-generated reflections, i.e. forward-scattered transmitted waves (and so-called fast...

Comparison of monotonicity challenges encountered by the inverse scattering series and the Marchenko de-multiple method for elastic waves

The reflection response of strongly scattering media often contains complicated interferences between primaries and (internal) multiples, which can lead to imaging artifacts unless handled correctly. Internal multiples can be kinematically predicted, for example by the Jakubowicz method or by the inverse scattering series (ISS), as long as...

An acoustic imaging method for layered non-reciprocal media

Given the increasing interest for non-reciprocal materials, we propose a novel acoustic imaging method for layered non-reciprocal media. The method we propose is a modification of the Marchenko imaging method, which handles multiple scattering between the layer interfaces in a data-driven way. We start by reviewing the basic equations for wave...

Tackling Different Velocity Borne Challenges of the Elastodynamic Marchenko Method

The elastodynamic Marchenko method removes overburden interactions obscuring the target information. This method either relies on separability of the so-called focusing and Green's functions or requires an accurate initial estimate of the focusing and Green's function overlap. Hitherto, F1- and G-+ have been assumed separable, whereas F1+ and...

Elastodynamic single-sided homogeneous Green’s function representation: Theory and numerical examples

The homogeneous Green’s function is the difference between an impulse response and its time-reversal. According to existing representation theorems, the homogeneous Green’s function associated with source–receiver pairs inside a medium can be computed from measurements at a boundary enclosing the medium. However, in many applications such as...

Unified wave field retrieval and imaging method for inhomogeneous non-reciprocal media

Acoustic imaging methods often ignore multiple scattering. This leads to false images in cases where multiple scattering is strong. Marchenko imaging has recently been introduced as a data-driven way to deal with internal multiple scattering. Given the increasing interest in non-reciprocal materials, both for acoustic and electromagnetic...

Elastodynamic Plane Wave Marchenko Redatuming: Theory and Examples

The Marchenko method is capable to create virtual sources inside a medium that is only accessible from an openboundary. The resulting virtual data can be used to retrieve images free of artefacts caused by internal multiples. Conventionally, the Marchenko method retrieves a so-called focusing wavefield that focuses the data from the recording...

Elastodynamic single-sided homogeneous Green's function representation: Theory and examples

The homogeneous Green’s function is the Green’s function minus its timereversal. Many wavefield imaging applications make use of the homogeneous Green’s function in form of a closed boundary integral. Wapenaar et al. (2016a) derived an accurate single-sided homogeneous Green’s function representation that only requires sources/receivers on an...