SEISMIC AND PETROPHYSICAL ANALYSES FOR HYDROCARBON PROSPECTING OF THE LOWER ACACUS FORMATION IN THE NC4 FIELD OF THE GHADAMIS BASIN, LIBYA

The lower Acacus Formation is one of the most productive oil and gas reservoirs in the Libyan district of the Ghadamis Basin. It extends laterally across several oil and gas fields and predominantly contains interbedded sandstone and shale deposited during the late Silurian. 3-D seismic reflection data and petrophysical analysis provide insights into the reservoir evaluation and identification of prospect area. The amplitude map of the lower Acacus is generated from the 3-D seismic data to determine the best targets for hydrocarbon exploration. Furthermore, the time structure map of the lower Acacus reveals the presence of high and low structural features, which can be interpreted as an anticline that may be considered as the main trap in the study area. Petrophysical analysis is carried out using a suite of wire-line logs obtained from three well to determine the quality of the lower Acacus reservoir. The petrophysical parameters are an average thickness of 150 m, an average porosity of 0.17, an average Gamma-ray clean of 0.54, an average formation water resistivity of 0.13, and an average water saturation of 0.38. Finally, three areas have been selected for drilling for the purpose of oil and gas explorations based on the seismic and petrophysical analyses. The volumes of oil in place for the three prospect areas are calculated using Kingdom Suite software.