The influence of geological processes on the change in the reservoir properties of the Shiranish formation in the Euphrates basin (Syria)

UDK: 551.24

DOI: 10.24887/0028-2448-2025-6-24-28

Key words: source rocks, Euphrates graben, Shiranish formation, oil and gas content, Syria, unconventional reservoir, porosity, permeability

Authors: A. Saleh (Gubkin University, RF, Moscow); A.S. Kurushina (Gubkin University, RF, Moscow); S.F. Khafizov (Gubkin University, RF, Moscow); K.I. Dantsova (Gubkin University, RF, Moscow)

The article explores the change in the reservoir properties of the Shiranish formation in the Euphrates basin influenced by various geological processes. The Shiranish Formation is divided into two units: the Upper Shiranish and the Lower Shiranish. This article focuses on the Upper Shiranish Formation. It consists of clay-carbonate rocks of Upper Cretaceous age. Typically, it represents a source rock enriched with organic matter, possessing hydrocarbon generation potential. However, while drilling a well in the South Kishma field, oil inflow was obtained from the Upper Shiranish Formation. Consequently, the unit was studied in greater detail through comprehensive geological and geophysical investigations to thoroughly analyze the type of its pore space and reservoir properties. Patterns of fracture formation were examined, along with more active periods of tectonic restructuring during geological time. The results obtained during seismic surveys and geophysical studies in wells were interpreted. Core samples were analyzed using various rock study methods, including scanning electron microscopy. Geological models of the South Kishma field were created to establish different hydrodynamic scenarios that could be considered further during field development. Based on all the results of the work performed, the oil reserves of the Upper Shiranish Formation in the South Kishma field were calculated.

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