Reservoir characterization of an x-field, offshore Niger Delta, Nigeria, using well data

Abstract

Petrophysical parameters of an oil field in the Niger Delta, Nigeria, were analyzed and characterized using well log data. The well log data were used to determine the hydrocarbon depth (2757 to 3591 m) and lithology of the field. Shale volume (V sh ) was calculated using linear and Larinov equations while the Archile equation was used to determine the water saturation. The study revealed water saturation of 0.035 to 0.426 and good porosity range of 0.105 to 0.152. The bulk volume of water ranged from 0.005 to 0.049 while the bulk volume of hydrocarbon ranged from 0.067 to 0.130. Hydrocarbon saturation of 0.574 to 0.965 was estimated across the reservoirs. The estimated value of moveable hydrocarbon saturation (S hmov. ) is less than 0.70 and was therefore inferred to be moveable. The well-seismic tie revealed synthetic and antithetic growth faults, roll-over anticlines, back-to-back and collapse crests as the major faults in the area, trending NW-SE. The model horizon obtained for the field shows that the eastern part of the field with maximum contour closures corresponds to the area with maximum hydrocarbon accumulation.