Scientific Quarterly Journal of Geosciences

Scientific Quarterly Journal of Geosciences

Petrography and Paleogeography of the Neogene Sediments in Talkheh-Rud Basin, between Tabriz and Ahar

Document Type : Original Research Paper

Authors
Fereydoun Sahabi 1
Hasan Mohseni 2
1 Department of Geology, Faculty of Sciences, Tehran University, Tehran
2 Department of Geology, Faculty of Sciences, Bu Ali Sina University, Hamedan
Abstract
The lower Miocene sediments in the Talkheh Rud Basin, half way between Tabriz and Ahar, consist of four lithofacies namely sandstones, shales, pyroclastics, and carbonates, while the last two Lithofacies are proportionally less frequent in the area. Sandstones are mostly submature, most probably due to a short distance between the site of deposition and the source area, as well as a high rate of sedimentation. Mineralogical composition of the sandstones shows that they have been originated from plutonic and volcanic masses and range between lithicarkose to feldspathic lithic arenite. Leaching of soluble material had led to significant number of secondary porosities to qualify these sandstones to host the mineralizing solutions and mineral deposits.
The Lower Miocene stratigraphic sequence in the studied area is of cyclic nature, and the cycles show a fining upward trend. This is an indicative characteristic for fluvial deposits in a meandering regime connected to deltas and closed basin.
Subjects
 
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Scientific Quarterly Journal of Geosciences
Volume 4, Issue 13
Autumn 1994, Vol. 4, No. 13
Autumn 1994
Pages 2-13