Structural Framework and Petroleum Systems of the Kurdistan Region of Northern Iraq: An Integrated Laboratory and Basin Analysis
DOI:
https://doi.org/10.26565/2410-7360-2026-64-01Keywords:
Kurdistan Region, Zagros Fold and Thrust Belt, petroleum system, Rock-Eval pyrolysis, core analysis, structural framework, thermal maturity, fractured carbonate reservoir, Sargelu Formation, Qamchuqa FormationAbstract
Problem Statement and Purpose. The Kurdistan region of Northern Iraq is situated in the highly deformed sector of the Zagros fold and thrust belt. This is a major hydrocarbon province that has undergone significant compartmentalization in its structural evolution. Although there is evidence of hydrocarbon seepage and known hydrocarbon reserves in the region, it is essential to understand the intricate relationships between the multiphase tectonic evolution and petroleum systems, which warrant the use of integrated analytical techniques. The aim of the current study is to identify the structural framework of the region and highlight the importance of laboratory experiments in petroleum systems.
Methods. The structural zones were defined by integrating available geological and geophysical data. An extensive laboratory workflow has been developed to obtain data on 125 source rock samples using Rock-Eval pyrolysis (TOC, Tmax, HI) and 110 reservoir core samples to measure porosity and permeability according to KRI benchmark parameters, investigating the Jurassic and Cretaceous formations.
Results. The structural analysis divides the area of investigation into three zones of stratigraphic interest: the Foothill, High Folded, and Imbricate zones, which are marked by extensive, doubly plunging anticlines. Laboratory-based studies have identified the Jurassic-age Sargelu and Naokelekan formations as prime oil-bearing source rocks, with average TOC values of 3.5% and 5.0%, respectively. These formations are concentrated mainly in the main oil window, with Tmax values between 440 and 470°C. Petrophysical studies on the Qamchuqa Formation have identified it as a two-porosity system, with an average matrix porosity of 12.1%. The micro-fractured system shows increased permeability up to 500 mD.
Conclusions. The integration of structural interpretation with rigorous laboratory geochemical and petrophysical data offers the benefit of reducing exploration risks. The advantage of this experimental approach is the ability to quantitatively assess the maturity of the source rocks and the deliverability of the reservoir in the highly deformed Zagros Foreland.
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