  Marchenko redatuming is a novel scheme used to retrieve up- and down-going
Green's functions in an unknown medium. Marchenko equations are based on
reciprocity theorems and are derived on the assumption of the existence of
functions exhibiting space-time focusing properties once injected in the
subsurface. In contrast to interferometry but similarly to standard migration
methods, Marchenko redatuming only requires an estimate of the direct wave from
the virtual source (or to the virtual receiver), illumination from only one
side of the medium, and no physical sources (or receivers) inside the medium.
In this contribution we consider a different time-focusing condition within the
frame of Marchenko redatuming that leads to the retrieval of virtual plane-wave
responses. As a result, it allows multiple-free imaging using only a
one-dimensional sampling of the targeted model at a fraction of the
computational cost of standard Marchenko schemes. The potential of the new
method is demonstrated on 2D synthetic models.
