Geochemistry of Sandstones from the Aghajari Formation, Folded Zagros Zone, Southwestern Iran: Implication for Paleoweathering condition, Provenance, and Tectonic Setting

Abstract

The Late Miocene- Pliocene Aghajari Formation is exposed throughout the Folded Zagros Zone and consists of fluvial sediments. Aghajari Formation sandstones are characterized by low to moderate SiO₂ contents, variable abundances of major elements and a relatively high proportion of ferromagnesian elements. Evidence from discrimination diagrams of sedimentary provenance, tectonic setting, major element geochemistry, and Sc/Th, Cr/Th, Co/Th, Zr/ Sc, La/Sc, La/Co, Cr/Sc, and Y/Ni values show that the Aghajri Formation sediments were derived from felsic and intermediate sources. The chemical index of alteration (CIA: 59.2– 77.14) revealed low to moderately weathered source rocks. The major and trace element concentrations indicate deposition in an active continental margin and passive continental margin settings.