The petrogenesis of Saricimen (Caldiran-Van) quartz monzodiorite: Implication for initiation of magmatism (Late Medial Miocene) in the east Anatolian collision zone, Turkey

The Saricimen porphyry is exposed as a sub-volcanic pluton within the Upper Cretaceous ophiolitic rocks in East Anatolian Accretionary Complex. The pluton is quartz monzodioritic in composition consisting of feldspar, hornblende, and biotite phenocrysts set in a fine-grained matrix. Major element geochemistry indicates the pluton is of high-K, calc-alkaline, metaluminous character, with a low (0.81-0.90) Aluminum Saturation Index (ASI). Trace element and sulfur isotope geochemistry suggests that the Sancimen porphyry was mantle-derived and contaminated by crustal materials during ascent. Tectonically, this and related volcanic and plutonic rocks in eastern Turkey and Iran are subduction-related and comprise the earliest documented neotectonic igneous activity associated with the final closure of the neo-Tethys between the Arabian and Eurasia plates at similar to 14-13 Ma. (C) 2010 Elsevier B.V. All rights reserved.