The central Persian Gulf is of paramount economic importance as it hosts the world’s largest gas field. Within this region, the Late Permian Dalan Formation and the Early Triassic Kangan/Upper Khuff Formation act as the primary gas reservoirs. The widespread Early Triassic deposits are significant gas reservoirs not only in the central Persian Gulf but also in the Zagros Mountains of Iran and neighboring Arab nations. As global energy demand escalates, the strategic significance of this region within the hydrocarbon market necessitates a comprehensive study. Despite considerable advancements in petroleum geology and the assessment of reservoir quality, there remains a notable knowledge gap concerning the sedimentary environments and facies characteristics of these formations. An integrated approach that combines sedimentological, petrophysical, and core analysis data is essential for optimizing hydrocarbon exploration and production strategies in these reservoirs. One of the primary challenges facing Triassic gas reservoirs in the central Persian Gulf and the Middle East is the limited availability of gas extraction zones. To overcome the existing limitations, a new zoning was established based on the model of sedimentary environments and the microfacies of the studied succession. The identification of these new zones was conducted through foundational studies of the sedimentary environment, microfacies, core analysis, and petrophysical data. The conducted studies have led to the identification of new areas and an increase in gas production. Five sedimentary environments and twelve microfacies were recognized within the Early Triassic succession. The results show that the shoal environment has the highest reservoir quality, with permeability and porosity of 105.6 mD and 34.1%, respectively, establishing it as the primary reservoir. Furthermore, the tidal environment under Highstand Systems Tract (HST) conditions presents permeability and porosity values of 9.35 mD and 5.3%, introducing it as a newly identified secondary reservoir in this succession. In microfacies analysis, the dolomitic ooid grainstone microfacies demonstrates the highest reservoir quality, exhibits the highest reservoir quality, with permeability and porosity values averaging 329.96 mD and 17.2%, respectively. The ooid grainstone microfacies ranks second in reservoir quality, with permeability and porosity values of 139.45 mD and 13.2%, respectively. Both of these facies were deposited in a shoal environment. Additionally, the coarse-crystalline dolostone facies, resulting from the degradation neomorphism of carbonate sands, ranks third in reservoir quality with 83.78 mD permeability and 6.26% porosity deposited in a tidal environment. The findings of this research can be extrapolated to other carbonate reservoirs deposited in homoclinal ramp environments.

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