Residual and Commercial Gas Discrimination by Spectral Decomposition Using Ultra-Far Stacked Seismic Data, Nile Delta, Egypt

Summary One of the big challenges facing operators in the on-shore Nile Delta is the discrimination between residual gas saturations and mobile commercial gas. The application of spectral decomposition and frequency attributes on pre-stack seismic data has opened the door to think about the relationship between frequency attenuation and reservoir properties. The main motivation of this study is the existence of a potential accumulation, with a very good seismic response, extremely comparable to that observed in a major producing field nearby. The results of a well drilled in this prospect were not encouraging and the well was classified as a dry well with gas shows (gas saturation in the tested reservoir reached 28%). We will see in this study how spectral decomposition can be used to discriminate between low gas saturations and mobile, commercial gas in the area of study.