Stratigraphy, provenance and tectonic setting of Qandi Bolagi sandstone in the middle part of the Upper Red Formation (SW Zanjan)

Authors

1 M. Sc. student, Dept., of Geology, Faculty of Sciences, University of Zanjan, Zanjan, Iran

2 Assoc. Prof., Dept., of Geology, Faculty of Sciences, University of Zanjan, Zanjan, Iran

3 Managing director of Simin Madan Alborz Company, Zanjan, Iran

Abstract

The Qandi Bolagi area, where the Upper Red Formation has a significant expansion, is located in the northwest of Zanjan province, and in the Central Iranian zone. The Upper Red Formation (URF) in this area with 2354 meters thickness mainly divided into two parts. The lowermost parts of the URF consist of colorful marl and separated from the Qom Formation by a gypsum layer. The upper parts include red and green marls with alternating layers of red to greenish-gray sandstone and conglomerate. Petrographic studies of the sandstones in the Qandi Bolag region, which hosts Pb-Zn mineralization, indicate the presence of quartz particles (mainly undulose extinction) with an abundance of about 24%, feldspar (mainly orthoclase) with an abundance of 12%, and metamorphic and sedimentary pebbles with an abundance of 28%. According to Folk's classification, it can be stated that the studied sandstones are mainly fine- to medium-grained immature calcareous feldspathic litharenite to litharenite. The obtained data consider the source rock of these sandstones in a semi-arid climate and from intermediate to felsic rocks, which are mainly derived from carbonate rocks belonging to the Qom Formation, fine to medium-grained siliciclastic rocks, metamorphic rocks, cherts and intermediate to felsic igneous rocks exposed in the area (belonging to the Takab complex). Based on common triangular diagrams, the tectonic position of these sandstones is considered the active continental margin and the foreland basin.

Keywords

Files

History

  • Receive Date: 14 August 2024
  • Revise Date: 27 September 2024
  • Accept Date: 29 October 2024

Share

How to cite

Statistics