Seismic interferometry applied to surface reflection data (with source and receivers at the surface) allows to retrieve virtual-source gathers at the position of receivers, where no source was shot. As a result of the crosscorrelation of all primary and multiple reflections, the virtual-source gathers contain retrieved physical reflections as well as non-physical (ghost) reflections also called spurious multiples. We show that a significant part of the ghost reflections can be suppressed by using surface-related multiple elimination on the active data advantageously. The method that we propose consists in retrieving the strong ghost reflections mainly from the crosscorrelation of primaries only and in subtracting this result from the virtual-source gather retrieved from all the data. The resulting new virtual-source gathers provide a better estimate of the reflection response since it is now less polluted by undesired non-physical events that may bring ambiguity in the interpretation. This is better to make a more effective use of the virtual-source gathers, for example for imaging.
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