For a better understanding of carbonate reservoirs, the relationships between stratigraphic features and heterogeneities are important for petroleum geologists. This study conducts detailed analysis and interpretation of microfacies, petrophysical-log, diagenesis, paleoenvironment, seismic stratigraphy, and seismic attributes to identify stratigraphic features that are significant concerning the heterogeneities commonly encountered in carbonate reservoirs. The Cenomanian-Early Turonian Sarvak Formation in the Abadan Plain of southwest Iran was deposited on a shallow carbonate platform. This formation has some distinctive stratigraphic features, including zones of sub-aerial exposure, rudist build-ups, sinuous channels, and paleo-valley deposits in four, third-order stratigraphic sequences. Vertical and lateral continuity and stratal geometry make it possible to distinguish the periodicity of the carbonate cycles in the sequences studied. These cycles reveal a strong interaction between the paleoenvironment, sea-level fluctuations, and local tectonic activities. Two distinct time intervals discriminate transgression/high-stand and low-stand systems that formed the multi-story stratigraphic features and heterogeneities, each with different effects on the reservoir characteristics. The rudist build-up, paleo-valley filling, and highly sinuous channels formed during high-stand conditions, while sub-aerial exposure, karstification, clay fillings, and rudist debris developed during the low-stand conditions associated with low sea levels. These stratigraphic elements formed significant reservoir heterogeneities at regional and local scales, which impact sequence correlations and rock properties. The analysis demonstrates that some zones displaying the best reservoir quality within the Sarvak formation are located within some of these heterogeneous stratigraphic features, making it important to delineate them in detail.

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