Petrophysical Analysis and Reservoir Characterization of the Miocene Jeribe, Dhiban, and Euphrates Formations in a selected well in Jambour Oilfield, Kirkuk Area, NE Iraq

The Miocene Jeribe, Dhiban, and Euphrates formations are considered attractive reservoir package in the petroleum exploration processes in Iraq. In this study, this package has been investigated from reservoir characterization point of view from a selected well (Ja-46) in the Jambour Oilfield in northern Iraq. The analysis of the wireline log data revealed that the Dhiban and Euphrates formations are clean with less than 10% shale content, while zones with relatively higher percentages of shale content observed in the middle part of the Jeribe Formation. Dispersed type of distribution was the common feature of the shale in the Jeribe and Dhiban Formation with additionally laminar type in the Euphrates Formation. The Jeribe Formation has porosities ranging from less than 10% to over 20%. The upper part of the Dhiban Formation has two different zones with porosities between 15% and 30%, while the majority of the Euphrates Formation has porosities greater than 20%. The permeability in the Jeribe Formation generally ranges from 2 mD to 40 mD and the Dhiban Formation of negligible permeability except for two intervals at its upper part which showed permeabilities exceeding 70 mD. Most parts of the Euphrates Formation have good permeability, occasionally reaching 170 mD. More than 97% of the reservoir units RU-J1, RU-J2, and RU-J4 in the Jeribe Formation are payable, whereas the reservoir unit RU-J3 only displays approximately 56% of the unit as payable. Just 7% of the reservoir unit RU-D2 of the Dhiban Formation is payable, compared to roughly 47% of the RU-D1 reservoir unit in the upper part of the formation. The 8 m gross thickness of the reservoir unit RU-E2 at the center of the Euphrates Formation is completely payable, while at least 94% of the gross thicknesses of the other three reservoir units of the formation have been found payable. Approximately 29% of the Jeribe Formation, 8% of the Dhiban Formation, and 80% of the Euphrates Formation are productive when using the 0.6 movable hydrocarbon index cutoff.