A Hybrid Approach to Petrophysical Characterization of the Nahr-Umr Formation in the Abu-Amood Oil Field: Combining Statistical and Conventional Methods

Ahmed, Mohammed Abdullah; Al Said Naji, Jassim Mohammed; Ali, Alyaa Mahmood

doi:10.22059/ijmge.2026.404531.595326

A Hybrid Approach to Petrophysical Characterization of the Nahr-Umr Formation in the Abu-Amood Oil Field: Combining Statistical and Conventional Methods

Articles in Press

Document Type : Research Paper

Authors

Mohammed Abdullah Ahmed

Jassim Mohammed Al Said Naji

Alyaa Mahmood Ali

Petroleum Engineering Department, College of Oil and Gas Engineering, University of Technology

10.22059/ijmge.2026.404531.595326

Abstract

The Nahr-Umr Formation, a subsidiary reservoir in the Abu-Amood oilfield in southern Iraq, will be the focus of this study, which will analyze well log data from four wells using two distinct approaches—statistical and traditional interpretation—and compare the results to ensure that the statistical approach is as reliable as the log interpretation. The investigation began by assessing the formation's petrophysical properties, such as water saturation, shale volume, and porosity, using the traditional approach. The log data was then analyzed using statistical techniques, specifically hierarchical clustering and Self-Organized Map (SOM) methods, to divide the formation into subunits (zonation) based on its petrophysical characteristics and identify the most effective reading in the estimation process.

This combined strategy illustrates the efficacy of using traditional and statistical methods to enhance reservoir characterization. Both approaches gave consistent results, therefore the formation could be separated into four different units: NU1, NU2, NU3, and NU4. NU1 is the first oil-bearing zone in the Nuhr-Umr formation, consisting primarily of limestone with a small thickness but acceptable properties (low shale volume, high porosity, and water saturation). NU2 and NU4 are predominantly made of shale, but NU3 is characterized by sandstone with high effective porosity and low shale volume and water saturation, as well as good thickness, making this unit the main producing unit in the formation.

Keywords

Logging Interpretation

Cluster Analysis

Nahr-Umr Formation

Abu-Amood Oil Field

Subjects