Overburden Imaging in the Barents Sea

Our second example comes from the Barents Sea, in water depths of 250 to 300 m. Here imaging of the complex overburden is significantly improved using SWIM.

The SWIM data was processed at 6.25 m x 6.25 m sampling, and up to 240 Hz. Not only did the imaging use high-resolution FWI velocities, SWIM also facilitated their effective QC during the model building phase, by defining the near-surface reflectivity that could be used to gauge the FWI model conformity with shallow data.

In the SWIM images, the orange arrows indicate locations where no amplitude anomalies are shown in the conventional processing. However, the SWIM images show isolated anomalies that need further assessment.

 

Depth slice showing dramatic improvement in resolution with SWIM imaging of the shallow hazards. The acquisition footprint is clearly obvious on the left hand side image and this obscures the resolution of the shallow gas. In comparison the SWIM depth slice shows the elimination of the footprint and excellent resolution of small details such as glacial striations and evidence of shallow gas (arrow).

 

Reprocessing using SWIM to improve resolution and AVO in the shallow part of the section revealing shallow gas hazards in the area (arrow).