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.