Petrophysical Evaluation and Hydrocarbon Prospectivity Determination of Osaka Field, Niger Delta, Nigeria

Abstract

Petrophysical evaluation and hydrocarbon prospectivity of Osaka Field in Niger
Delta Nigeria was carried out with the aim of identifying the reservoir and
estimating the hydrocarbon-bearing potentials of the reservoirs. Composite suite
of well logs comprising gamma ray, resistivity, neutron porosity, density porosity
and sonic logs were acquired from an oil producing company. Four wells, Osaka
well 001, well 002, well 003 and well 004 were used for the exercise. The logs were
uploaded into the Petrel Workflow software. Three reservoirs R1, R2 and R3
were correlated and petrophysical parameters (porosity, permeability, water
saturation, irreducible water saturation, and hydrocarbon saturation and
formation factors) computed. Hydrocarbon discrimination was done using the
overlay of the neutron and the density porosity logs. The petrophysical analysis
result showed that the water saturation varies from 15% to 46% in well 1, 38%
to 46% in well 2, 40% to 65% in well 3 and 26% to 40% in well 4. The
irreducible water saturation also varies from 4% to 8% in well 1, 6% to 8% on
well 2, 5% to 7% in well 3, 5% to 7% in well 4. Based on the results obtained
from the hydrocarbon saturation which vary from 53% to 84% in well 1, 54% to
62% in well 2, 40 to 69% in well 3 and 60% to 74% in well 4. It is concluded
from the study that reservoir rocks in the studied wells in Osaka field generally
are prospective and could be exploited for exploration purposes.