Chi angle scan for investigating gas water contact of a Pliocene reservoir in the offshore East Nile Delta, Egypt
نویسندگان
1 Assistant Professor, Geophysics Department, Faculty of Science, Cairo University, Cairo, Egypt
2 M.Sc Graduate, GeoEnergy Petroleum Services, Cairo, Egypt
doi
10.30499/ijg.2024.448952.1587چکیده
One of the main targets within the oil and gas industry is mainly the prediction of both fluids and lithology. Extended Elastic Impedance (EEI) technique is strongly recommended in facilitating reservoir characterization and in distinguishing between seismic amplitude anomalies caused by lithology and those caused by hydrocarbon. Chi angle scan range from 0° to 90° has been conducted to investigate a Pliocene prospect in the offshore East Nile Delta (ND), Egypt. The presence of a remarkable Gas Water Contact (GWC) in the study area helped in investigating the generated EEI volumes. The projections of Chi angles were either affected by lithology only or fluids only, or both lithology and fluids. The fluid volume was estimated at EEI35°, where the top of the gas sand is continuous because of the huge contrast with the overlaying shale and the high amplitude of the gas sand was shut off because of the variation of the fluid type from gas to water. This volume could clearly demonstrate the variation of different fluids with minimum lithology effect. The lithology volume with minimum effect of fluid was estimated at EEI90° (gradient volume), the bottom of the sand was shown on this volume regardless the type of the fluid. However, the base was challenging because of the insignificant contrast between the brine sand and the underlaying shale. The findings of this study can help in better understanding the implication of EEI technique in investigating a Pliocene gas prospect and delineating possible recommended locations for drilling in this field. Moreover, the results show how the technique successfully discriminates between different lithology and fluids.