Three-Dimensional Reservoir Characteristics Model (Porosity and Water Saturation) for Selected Wells of the Mishrif Formation in the Eridu Oilfield, Southern Part of Iraq

The Mishrif Formation, which is one of the field's primary reservoirs located in the Eridu oilfield in the southern part of Iraq, six oil wells were chosen in this study. Different well logs were examined for open wells represented by gamma ray, density, neutron, self-potential, sonic, and resistivity from which different petrophysical properties are extracted. The kind of rocks, the contacts and thickness of the strata, the formation depths, and the water- and hydrocarbon-bearing zones were all identified through the qualitative interpretation of the logs. Regarding the quantitative interpretation, which evaluates the reservoir's characteristics through calculations of the reservoir's porosity, the water and oil saturation, and other characteristics required to assess the research wells' reservoir units, where the study wells' logs were utilized were presented. The obtained petrophysical characteristics were dealt with and presented in the form of charts to clarify the distribution of these characteristics for the studied wells. The Mishrif Formation is divided into four units, which are from top to bottom CR-I, MA, CR-II, and MB, where the reservoir units have high porosity in most wells and are separated by hard rocks with low porosity. The water saturation percentage was high in hard rocks, and the percentage of residual and mobile hydrocarbons was high in the MB unit for some wells only and low in the MA unit.