Assessing Geohazards in Shallow Water

These images from the North Sea demonstrate the challenge of using conventional 3D seismic data for geohazard analysis when the water is shallow (30 m to 130 m) and a striking comparison with SWIM imaging.

The examples below show images produced from conventional processing (K-PSTM), and the results achieved on the same datasets using SWIM and including sea-surface reflections.

The SWIM vertical sections illustrate near-surface channels and short-wavelength features in both inline and crossline directions, which are not visible on the conventional processing.

Shallow time slices are uninterpretable using orthodox processing. In contrast, the high-resolution SWIM equivalent clearly shows anomalous amplitude features that require further geohazard assessment.  

Slide to compare: near-surface imaging of towed streamer data with very shallow water-bottom (30 - 130 meters). Slide the bar to the right to view results based on conventional processing (KPSTM), geohazards are not visible. Slide all the way to the left and compare with SWIM data that illustrates near-surface channels and short-wavelength features.

 

Slide to compare another example: results on the left side are based on conventional processing (KPSTM), and geohazards are not visible. The SWIM data on the right reveal near-surface channels and short-wavelength features.

 

Contrasting timeslices on the same dataset demonstrate the advantage of SWIM: Slide the bar to view a shallow timeslice using orthodox processing, then slide back to compare with a high-resolution SWIM equivalent that clearly shows anomalous amplitude features.