We need to re-think the acquisition and processing parameters for sea bottom seismic in the Arabic Gulf Conference Paper uri icon


  • Sea Bottom Acquisition is the standard seismic method for a large part of the Arabian Gulf. Typical for the region is shallow water and large velocity contrasts, i.e. high seismic velocity just below the sea bottom. This in essence represents a waveguide and has a very dominating effect on wave propagation and penetration. To understand the challenges and the opportunities this represent, we in this study are performing full acoustic and elastic modeling and then compare the predicted results with observed 4-component (4C) seismic data. We find that although the data is very complicated the simulations to a large extent can predict the observations. We thus conclude that the modern instruments as such are giving a correct picture of the wavefield and are not a part of the problem. The simulation demonstrates that we should expect extremely strong Scholte waves which indeed also are observed. Because of the wave trapping mechanism mentioned above, these waves keep rolling for a very long time. The way most acquisition is done they represent a considerable noise problem not only for the actual shot but also for subsequent shots. In addition these waves are under-sampled in space with the present acquisition systems. This gives rise to high noise levels that are difficult to remove because it is aliased. One positive opportunity is that we expect strong wave mode conversion to S-waves near the surface. We thus expect to see reflected S-waves in 4C data (S-down and S-up) if we record long enough. Modeling results also shows that they will have large variations with offset and basically are destroyed the way we typically process today. These waves might have important structural and lithological information if we can extract them properly. In sum; the acquisition challenge will be to sample much denser in space as well as shooting with much longer time difference to avoid unacceptable left over noise from previous shots. Obviously that might have large cost effects, but also large upside with regard to survey quality. In addition to noise removal one of the processing challenges will be to use model dependent processing to enhance the information from both the P- and S- waves. Copyright 2010, Society of Petroleum Engineers.

published proceedings

  • Society of Petroleum Engineers - 14th Abu Dhabi International Petroleum Exhibition and Conference 2010, ADIPEC 2010

author list (cited authors)

  • Berteussen, K. A., & Sun, Y

complete list of authors

  • Berteussen, KA||Sun, Y

publication date

  • December 2010