Open AccessReservoir sands characterisation involving capacity prediction in N<sub>Z</sub> oil and gas field, offshore Niger Delta, Nigeria
Author(s) -
Anthony I.Nzekwu,
Richardson M. Abraham-A
Publication year - 2022
Publication title -
aims geosciences
Language(s) - English
Resource type - Journals
ISSN - 2471-2132
DOI - 10.3934/geosci.2022010
Subject(s) - petrophysics , hydrocarbon , permeability (electromagnetism) , porosity , mineralogy , analytical chemistry (journal) , chemistry , geology , geotechnical engineering , environmental chemistry , biochemistry , organic chemistry , membrane
Hydrocarbon exploration is a high-risk venture; therefore, pre-determining reservoirs' capacities is pertinent, reducing associated uncertainties regarding hydrocarbon presence and production. This study delineates hydrocarbon-bearing sands, determines the reservoir area extent, computes the associated petrophysical parameters and presents the reserve volume estimation based on wireline logs with integrated 3-D seismic surveys. It evaluates and indicates three (3) hydrocarbon-bearing reservoirs sands (N Z(R1) , N Z(R2) and N Z(R3) ) of varying thicknesses (h) across three (3) wells reservoirs N Z(R1) , N Z(R2) and N Z(R3) . The reservoir properties, including porosity (Ф), free fluid index (FFI), permeability (K), fluid saturations and reservoir thickness (h), represent potentially viable hydrocarbon reservoir units across the field. It presents the estimation of the recovery factor based on the FFI values. Across the reservoirs, Ф is 0.28 in N Z(R1) , 0.27 in N Z(R2) and 0.26 in N Z(R3) . FFI is 0.26 in N Z(R1) , 0.25 in N Z(R2) and 0.26 in N Z(R3) . K is 10388 mD in NZ (R1) , 8304mD in N Z(R2), and 6580 mD in N Z(R3) . Water saturation (S w ) is up to 0.4, 0.36 and 0.20 with the associated hydrocarbon saturation (S h ) of 0.60, 0.64 and 0.80 corresponding to N Z(R1) , N Z(R2) and N Z(R3) . Considering the delineated reservoir areas based on the prevailing fault assisted structural style, the total volume of recoverable oil is 11.3×10 6 , while the gas capacity is 1.8 ×10 9 cuft. These findings will aid the field's oil and gas reservoir developmental activities and serve as reference points to related studies involving similar objectives.