Geochemical Features and Magma Source Regional Characteristics of the Post-Collisional Plio-Quaternary Gozucu (taslicay-Agri) Volcanics, Eastern Anatolia, Turkey

Abstract

This study aimed to determine the petrographic and geochemical features of the Plio-Quaternary Gozucu (Taslicay-Agri) volcanics. These volcanics have subalkaline, calc-alkaline, high-K-series and shoshonitic features and are composed of basalt, andesite, trachyandesite, trachydacite and dacites. The Gozucu volcanics exhibit enrichment in light rare earth elements (LREE) and large ion lithophile elements (LILE) while showing depletion in heavy rare earth elements (HREE) and high field strength elements (HFSE). The average Sr and Ba values of Gozucu volcanics are close to continental crust values (Sr-379 ppm Ba-639 ppm), which means that these rocks were contaminated by the continental crust during formation. Low Nb/La (5.13 ppm) and high Ba/Rb (16.75 ppm) ratios indicate that the contribution of sediments was more than that of fluids during the contamination process of the Gozucu volcanics. Positive and negative trends of major and trace elements in the variation diagrams indicate fractional crystallization and a single mantle source. The Gozucu volcanics occurred with a partial melting of the spinel-rich lithospheric mantle source with 0.1-3% partial melting in the continental arc environment after the collision.