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Document Type

Original Article

Abstract

This study evaluates the petroleum generating potential of the Middle-Late Jurassic Sargelu and Naokelekan Formations across distinct tectonic zones in the Kurdistan Region, Iraq. Source rock quality is assessed through geochemical analyses of organic matter (OM) quantity, type, thermal maturity, and key factors influencing hydro-carbon generation. Rock-Eval pyrolysis was performed on outcrop samples from five sections located within the Imbricated and High Folded Zones of the Zagros Fold-Thrust Belt. Results demonstrate significant variability in total organic carbon (TOC) content, hydro-carbon generation potential (as reflected by S1, S2, and genetic potential values.), and kerogen types across these zones. The Sargelu and Naokelekan formations exhibit excellent source rock potential in the Banik and Gara sections, with TOC values up to 20 wt% and S2 values exceeding 80 g HC/gr rock. Kerogen types in these areas are predominantly oil-prone Type II and mixed Type II/III, with thermal maturity within the oil generation window (Tmax ~439°C in average). Conversely, samples from the Rania, Sargelu, and Chnaran sections demonstrate poor hydrocarbon potential, characterized by lower values TOC (

Receive Date

06/09/2025

Revise Date

09/01/2026

Accept Date

15/02/2026

Publication Date

3-17-2026

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