Reservoir Characterizations Related to Petrophysical Assessment of the Khasib Formation in Ahdab Oilfield, Central Iraq

The present study focused on evaluating the petrophysical properties and reservoir characteristics of the Khasib Formation depending on the combination and processing of open hole well logs for five wells at the Ahdab oil field: AD-1, AD-2, AD-3, AD-4, and AD-5. The Ahdab oil field is located in Wasit Governorate to the southwest of Kut City. The oil field is located within the Outer Platform of the Arabian Plate, Mesopotamian Foredeep. The petrophysical properties were determined using Schlumberger Petrel software (version 2022) by analyzing the results of interpretation and computer-processed modeling. The available well logs data classified the Khasib Formation into four units based on the variation in their petrophysical properties: Kh1, Kh2, Kh3, and Kh4. The results indicated that Kh2 is a good reservoir unit and Kh4 is moderate, characterized by high hydrocarbon saturation (50%-75%), low shale content (2%-20%), and high effective porosity (10%-30%). Conversely, units Kh1 and Kh3, as well as Kh4 in certain contexts, were characterized by poor petrophysical properties (non-reservoir properties) due to low hydrocarbon saturation and low effective porosity caused by an increase in shale volume.