Processing and interpretation of shallow water seismic data for CO2 injection

Abstract

2-D seismic data were acquired in Yeong-il Bay of Korea in search of proper prospects for CO2 injection into an offshore basin. The unfavourable situation for operation and very shallow water prevented the operator from obtaining quality data. Small number of channels and short offsets incapacitated velocity analysis and migration. Main efforts have been thrown into finding out the best processes to attenuate linear noises and strong short-period multiples raised from the shallow water that masked the whole data. The processing methods ascertained to be useful for this purpose are DENOISE, DWD (deterministic water-layer demultiple), and t-p deconvolution, which were applied by using Omega 2 processing system. The resultant images are successfully free from the strong noise and revealed the geological structures obscured by the noise. The processed data were geologically interpreted to identify the prospective formations in the basin so as to inject carbon dioxide into them.