Geochemistry and tectonic setting of the Abu-Marawat metavolcanics, Central Eastern Desert—Egypt

Abstract

This article discussed the petrographic and geochemical characteristics and tectonic setting of Abu-Marawat metavolcanics as part of the Arabian–Nubian Shield in the Central Eastern Desert of Egypt. They comprise metamorphosed basalt, basaltic andesites, dacite, and rhyolites associated with their volcaniclastics. The presence of large amounts of pyroclastics infers that their magma were erupted in submarine environments. They underwent low-grade regional metamorphism related to greenschist facies during the Pan-African orogeny. The geochemical characteristics revealed that the metavolcanics are characterized by low-medium-k calc-alkaline affinity. Analyses of major and trace elements showed that these rocks are relatively enriched in large ion lithophile elements (LILEs; Ba, Rb, K, Pb, and Sr) and depleted in high field strength elements (HFSEs; Zr, Y, P, and Ti) proving subduction component. The marked depletion of specific trace and major elements from basalts to rhyolites reflected the magmatic fractionation. Chemical characteristics, tectonic discrimination diagrams, and N-MORB normalized spider plots of the present study support that their magmas were erupted in an arc setting.