Pre-migration residual multiple subtraction using post-migration matching for North Sea OBN data

In the North Sea, water bottom related surface multiples offer one of the largest challenges to a seismic processing project with a careful balance between multiple attenuation and primary preservation required when using a model and subtract approach. For Ocean Bottom Node (OBN) data Up/down deconvolution can be used to output the reflectivity where multiple and source signature will be removed, eliminating the need for an adaptive subtraction as part of the principle de-multiple process. Residual multiple can however still be present where the assumptions within the up/down deconvolution method do not adequately describe the reality of the data. Often, these residuals are only noticeable once migrated, particularly where a diffracted component is prevalent. In this paper, a method using the coherency of residual multiple evaluated on migrated and stacked data is used to drive pre-migration residual multiple attenuation through the use of a matched-subtraction.