Reservoir modeling of the Jeribe–Euphrates Formation in selected oil field, Missan Governorate, southeastern Iraq

The reservoir model represents a validated mathematical simulation based on a set of geological data and petrophysical parameters for the studied section. The study provides a realistic three-dimensional subsurface image of the spatial distribution of the reservoir properties of that section. The target of this study is to determine the reservoir characteristics of the Jeribe/Euphrates Formation within one of the Missan oil fields in southeastern Iraq. When the main petrophysical parameters (water saturation, effective porosity, and shale volume), which were mathematically processed in the Excel program, were used in designing three-dimensional reservoir models using the Surfer-13 program. The formation was divided into two reservoir units (jr-1, jr-2), where the results of the reservoir analysis of the petrophysical properties of both units showed good values for hydrocarbon saturation and effective porosity with a low ratio of shale volume in most of the study sections. Effective porosity maintains its favorable ratios in most directions, but water saturation ratios are increasing at the expense of hydrocarbon saturation ratios in the northwestern part of the field, which negatively impacts reservoir efficiency in that direction. Otherwise, the reservoir characterization of both units is improving significantly in all other directions, especially towards the site of well-1 at the crest of the anticlinal structure.