Abstract: Post-migration coherent noise removal by dip decomposition to enhance subsalt imaging in Gulf of Mexico
Editor’s Note: As a preview to our March 2018 RECORDER featuring the focus topic: Salt & Subsalt Imaging in the Gulf of Mexico, we present the following abstract for one of the featured articles.
In the Gulf of Mexico (GoM), with complex salt geometry, it is not unusual to see coherent noise in subsalt imaging. Such noise is detrimental to subsalt exploration and appraisal as they often lead to incorrect interpretations. The coherent noise is related to converted waves, intra-salt multiples, residual free-surface multiples, seismic data acquisition noise, and etc.
Seismic processing from improved demultiple and noise attenuation will reduce post-migration coherent noise. Often we found that post-migration coherent noise attenuation is required to enhance the seismic data quality prior to structural and stratigraphic interpretation. Our approach is to decompose seismic images into dip image partitions (DIPs). The residual multiples can be suppressed by matching the multiple image with the seismic image in different DIP components. Also, when noise model doesn’t exist, if there is enough dip separation between seismic events and coherent noise, the coherent noise can be removed by applying a 3D filter to the DIPs.
To view this full article, CSEG Members may access the March 2018 RECORDER issue here. If you are not a member this article will be released for public access in Fall 2018.