INTERPRETATION OF WELL LOG MODELS FROM E-FIELD IN THE NIGER DELTA SEDIMENTARY BASIN
Keywords:
well log models, pay zones, porosity, permeability, Net to Gross (NTG), fluid saturationAbstract
Interpretation of well log models in this research was achieved with the use of well log data from three (3) wells of an E-field in the Niger Delta sedimentary Basin. The well log data was processed with Petrel software (2010 version) which gives various well log signatures of the well logs resulting from the subsurface properties, in order to determine the subsurface lithology, the reservoir sand of interest, the hydrocarbon potential of the delineated reservoir, the petrophysical properties of the reservoir and the fluid contained in the reservoir. The logs used were the gamma ray, spontaneous potential, resistivity, density and neutron logs. The subsurface lithology of the formation of interest was identified as sand and shale, the reservoir was delineated as sand bodies. Although, there were several reservoirs with appreciable depth present across the wells, only two reservoirs (reservoir M and reservoir K) were chosen for detailed analysis, mapped and correlated across each of the wells. It was observed that reservoir (M) had a thickness of 50ft in OLJ 1, 50ft in OLJ4, 50ft in OLJ 5 and reservoir (K) had a thickness of 60ft in OLJ 1, 90ft in OLJ 4 and 70ft in OLJ 5. The petrophysical log used were the porosity log, permeability log, net to gross log and water saturation log. The average petrophysical properties of the reservoir (M) gave a porosity value of 0.23 (23%), permeability value of 1635mD, net to gross (NTG) value of 0.9, water saturation value of 38%, hydrocarbon saturation value of 62% and reservoir (K) gave a porosity of 0.23 (23%), permeability of 1442mD, net to gross (NTG) value of 1.0, water saturation 38% and hydrocarbon saturation of 62%, which indicates an excellent hydrocarbon reservoir system with much petroleum and gas prospect for hydrocarbons exploitation.
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