I. Yousef, V.P. Morozov, M. El-Kadi
Diagenetic clay minerals in Upper Triassic sand reservoirs of the Euphrates Graben (Syria)
DOI 10.31087/0016-7894-2018-6-137-147

Sandstone of the Upper Triassic oil reservoir (Mulussa F bed) is one of the main oil production targets. Tectonically, it is confined to the Euphrates Graben. Lithofacies analysis is carried out, and morphology of clay minerals making a part of the sandstone is investigated. We used radiography analysis, scanning electron microscopy, including microanalysis. The different roles of minerals in filling a sandstone pore space are shown. Among clay minerals, the following are predominating: kaolinite, illite, chlorite and mixed-layered clay mineral having illite-smectite composition. Kaolinite is a basic phase of clay minerals; it makes up to 81 % of total volume of clay mass. Morphologically, kaolinite forms hexagonal and pseudohexagonal blades and aggregates composed of crystals ranging in size from 10 to 15 µm. The latter form fan-like intergrowths 20 to 69 µm in size, which completely or partially fill pore space. Chlorites are usually found as granular overgrowths on the clastic grains; they make almost 13 % of clay mass in sandstone.


Key words: diagenetic, clay minerals; sandstone; Upper Triassic formations; Euphrates Graben; Syria.

For citation: Yousef I., Morozov V.P., El-Kadi M. Diagenetic clay minerals in Upper Triassic sand reservoirs of the Euphrates Graben (Syria). Geologiya nefti i gaza. 2018;(6):137–147. DOI: 10.31087/0016-7894-2018-6-137-147


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I. Yousef

Institute of Geology and Petroleum Technologies, Kazan Federal University, Kazan, Russia;


V.P. Morozov   Scopus   iD 

Institute of Geology and Petroleum Technologies, Kazan Federal University, Kazan, Russia;


M. El-Kadi

University of Damascus, Damascus, Syria;