Kazakhstan journal for oil & gas industryKazakhstan journal for oil & gas industry2707-42262957-806XKMG Engineering10895310.54859/kjogi108953Research ArticleConceptual model for the formation of Jurassic deposits of the Zhetybay East field based on sedimentological core analysisKhassenovAskhat G.a.khassenov@kmg.kzhttps://orcid.org/0009-0009-7933-4321UteyevRakhim N.<p>PhD</p>r.uteyev@kmge.kzhttps://orcid.org/0000-0003-3461-4118ImanbayevBakhyt A.b.imanbayev@kmge.kzhttps://orcid.org/0009-0004-9736-3453BassarbayAkbota Ye.a.bassarbay@kmge.kzhttps://orcid.org/0009-0003-2887-1481AlexeyevaYekaterina V.e.alexeyeva@kmge.kzhttps://orcid.org/0009-0007-3754-1264MorozovVitaliy N.vmorozov@advnrg-intl.comhttps://orcid.org/0009-0004-3592-0058KazMunayGasKMG EngineeringBranch of KMG Engineering «KazNIPImunaigaz»Advantage Energy International – FZCO30092026838191602202617062026Copyright © 2026, Khassenov A.G., Uteyev R.N., Imanbayev B.A., Bassarbay A.Y., Alexeyeva Y.V., Morozov V.N.2026<p><strong>Background: </strong>The geological structure of the Jurassic deposits in the Zhetybay East field is characterized by pronounced facies heterogeneity and complex spatial variability of reservoir properties driven by changes in depositional environments. The insufficient understanding of formation patterns and spatial distribution of facies bodies limits the accuracy of geological modeling and the prediction of productive zones. The study and interpretation of facies settings enable a detailed characterization of depositional environments, hydrodynamic regime parameters, and paleoenvironmental conditions, which form the basis for stratigraphic correlation, paleogeographic reconstructions, and applied geological predictions. In this context, there is a need for detailed sedimentological analysis of core material followed by integration of the obtained results with well log data and seismic survey data in order to improve the reliability of interpretation and refine the geological model of the field.</p> <p><strong>Aim: </strong>The aim of this study is to determine the facies environments of the Zhetybay East field based on core analysis results.</p> <p><strong>Materials and Methods:</strong> Historical data for each well in the field and laboratory results of core material analysis were used as the main sources of information. Core interpretation was performed using a sedimentological approach, including the analysis of lithological composition, textural and structural features, and diagnostic sedimentary structures. Based on the integrated interpretation of core and well data, facies analysis was carried out with the identification of genetic types of deposits and the reconstruction of their formation conditions.</p> <p><strong>Results:</strong> As a result of the sedimentological analysis of core material, a facies interpretation of the Jurassic productive deposits of the Zhetybay East field was performed. Based on the study results, the main depositional environments were identified and a conceptual sedimentological model of the productive interval of the section was developed.</p> <p><strong>Conclusion: </strong>The obtained results allow refinement of the geological model and improvement of the prediction of productive horizon distribution. In addition, they contribute to increased reliability of stratigraphic correlation. 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