Petrophysical Evaluation of H-field, Onshore Niger Delta Sedimentary Basin, Nigeria

Abstract

Petrophysical evaluations for three reservoirs, H_3, H_5 and H_7 in four wells, H-002, H-007, H-009 and H-011 were carried out to evaluate the distribution of hydrocarbon in the reservoir rocks found within H-field onshore Niger Delta.  A suite of well logs such as gamma ray (GR), resistivity (LLD), caliper (CALI), compressional sonic (DT) and density (RHOB) logs were analyzed over H-field and shale volume, total porosity, effective porosity, water saturation and permeability were the petrophysical parameters estimated. Three reservoir sand were identified and correlated from four wells (H-002, H-007, H-009, H-011) using gamma ray and the average thickness for the three reservoirs H_3, H_5 and H_7 estimated were 106.50 ft, 23 ft and 174.25 ft respectively. The average values of volume of shale, effective porosity, total porosity, permeability, water saturation and hydrocarbon saturation of the delineated reservoir sands are 16.04 ft, 3.14 ft and 24.18 ft for shale volume, 18.5%, 18%, 18% for effective porosity, 20.25%, 20.25%, and 20% for total porosity, 1582.3515 mD, 1278.8912 mD and 1570.058 mD for permeability, 44%, 42.75% and 44% for water saturation and 56%, 57.25% and 56% for hydrocarbon saturation for reservoirs H_3, H_5 and H_7 respectively. Due to the low value of shale volume, water saturation and the good porosity and permeability nature of the reservoir which depicts the distribution of hydrocarbon in the wells within the field.  Core data Acquisition, volumetric analysis and Interpretation within the reservoirs should be carried out to reduce uncertainties in exploration and production risk.