Ar-Ar dating and petrogenesis of the Early Miocene Taskapi-Mecitli (Ercis-Van) granitoid, Eastern Anatolia Collisional Zone, Turkey

The Early Miocene Taskapi-Mecitli granitoid that is located in the northern section of the Eastern Anatolia Collision Zone has typical I-type, metaluminous and calk-alkaline characteristics. It also contains mafic micro-granular / magmatic enclaves (MMEs). New Ar-Ar dating results show that the age of the Taskapi-Mecitli granitoid is similar to 23 Ma and it crystallised in the Early Miocene, in contrast to its previously known Cretaceous age. Identical crystallisation ages (similar to 23 Ma), similar mineral assemblages and geochemical compositions, and indistinguishable isotopic compositions of MMEs and host rocks imply that the MMEs are most consistent with a cumulate origin formed at earlier stages of the same magmatic system that produced the Taskapi-Mecitli granitoid.