Petrographic And Geochemical Features Of The Karlıca Volcanites (Hamur-ağrı)

Abstract

This study was carried out to reveal the petrographic and geochemical features of the rocks around Demirkapı (Hamur-Ağrı). The volcanites in the study area have subalkaline, calc-alkaline, high-K calc-alkaline and shoshonitic features and consist of andesite, dacite, ignimbrite and tuffs. These volcanic rocks show enrichments in light rare earth elements (LREE) and large ion lithophile elements (LILE) (Cs, Rb, Ba, K). The Nb/Yb and (Th/Nb)N ratios of the Karlıca volcanites range between 8.56-15.52 and 12.59-15.43, respectively. Average Sr and Ba values are 505.15ppm and626.16ppm, respectively, and these values are higher than average Sr and Ba values of the continental crust. These enrichments in Karlıca volcanites, and high Sr and Ba values suggest that crustal contamination is an effective process with fractional crystallization during the formation and evolution of the these rocks. © 2019, Hacettepe Universitesi Yerbilmleri. All rights reserved.