STRATIGRAPHY, CORRELATION, AND INDUSTRIAL-GEOPHYSICAL CHARACTERISTICS OF THE TRIASSIC DEPOSITS OF THE SEGHENDYK DEPRESSION (SOUTHERN MANGYSHLAK)

Стратиграфія, кореляція та промислово-геофізична характеристика тріасових відкладів Сегендикської депресії (Південний Мангишлак)
Zhiyenbayeva G. Kozhakhmet K. Khamzina B. Yerzhanova Z. Togizov K. Laiskhanov S.
2025 Natsionalnyi Hirnychyi Universytet

Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu
2025 Issue 6 23 - 34 pp.

Purpose. To refine the stratigraphic subdivision, lithological composition, and sedimentation environments of the Upper Triassic deposits within the Seghendyk Depression (Southern Mangyshlak) using geophysical data and core materials from exploration wells. Methodology. The study is based on an integrated analysis of geological and geophysical data, including gamma-ray logging, neutron-gamma logging, electrical resistivity logging, and spontaneous potential measurements, complemented by descriptions of core samples. Findings. Stratigraphic correlation was conducted for the Saura-Seghendyk, Zhangeldy, and Northern Karagie areas, enabling the identification of lithostratigraphic subdivisions within the Triassic sequence. Within the Upper Triassic succession, two formations were identified: the North Rakushechnaya Formation and the Bokand Formation, which differ in lithological composition and geophysical characteristics. The North Rakushechnaya Formation is subdivided into four members: argillite-gravelite, argillite-sandstone, argillite, and carbonate-terrigenous, representing an incomplete third-order transgressive sedimentary cycle. The Bokand Formation comprises two members, argillite-sandstone and sandstone-argillite, forming another incomplete cycle. In the Seghendyk Depression, a regular increase in the thickness of the North Rakushechnaya Formation (up to 865 m) was observed, primarily due to the thickening of the lower gravelite member, which exceeds the values recorded in adjacent tectonic zones. Based on the interpretation of geophysical data, a correlation stratigraphic scheme was developed uniting the Saura-Seghendyk, Zhangeldy, and Northern Karagie areas. Originality. For the first time, the internal structure of the Upper Triassic complex of the Seghendyk Depression has been detailed, identifying six lithostratigraphic members that reflect two incomplete sedimentation cycles. A refined stratigraphic framework is proposed, linking the Seghendyk Depression to the North Karagie Saddle and aligning it with the regional stratigraphic scale of Mangyshlak. Practical value. The developed stratigraphic model enables more accurate correlation of the Triassic sections in Southern Mangyshlak, improving the prediction of reservoir horizons within the promising Saura-Seghendyk, Zhangeldy, and Karagie areas during oil and gas exploration.

lithostratigraphic section , Seghendyk depression , Southern Mangyshlak , stratigraphic correlation , upper triassic

Text of the article Перейти на текст статьи

Yessenov University, Aktau, Kazakhstan
Zhangir Khan West Kazakhstan Agrarian and Technical University, Industrial Technical Institute, Uralsk, Kazakhstan
Limited Liability Partnership “GeoService-TK”, Almaty, Kazakhstan
International Educational Corporation, Almaty, Kazakhstan
Kazakh leading architecture and civil engineering academy, Almaty, Kazakhstan

Yessenov University
Zhangir Khan West Kazakhstan Agrarian and Technical University
Limited Liability Partnership “GeoService-TK”
International Educational Corporation
Kazakh leading architecture and civil engineering academy

10 лет помогаем публиковать статьи Международный издатель

Книга Публикация научной статьи Волощук 2026 Book Publication of a scientific article 2026