Petrological and geochemical characteristics of the diabase and metasomatised dikes from the Tekirova ophiolite (SW Anatolia, Turkey): Tectonomagmatic evolution of the southern Neotethys

Abstract

Ophiolites are widespread across the Anatolian plate and formed during the termination of different branches of the Neotethys ocean. The Tekirova ophiolite, situated in the Antalya ophiolite nappes in Southwest Anatolia, originated in the southern branch of the Neotethys. The former ophiolite consists of mantle and crustal sequences, in which, it is predominantly crosscut by the isolated diabasic dikes. Here, we have distinguished two dike types on the basis of their petrographic features and also degree of alteration. The relatively fresh types are generally named as diabase dikes. While the altered types are called as metasomatised dikes, and these dikes display ophitic to subophitic textures. The diabase and metasomatised dikes show enrichment in LILEs and depletion in HFSEs, indicating characteristics of suprasubduction zone ophiolites. This depletion of mobile elements may have been caused by metasomatism. The HFSEs versus HREEs diagrams show that the dikes were formed from 10 to 30% melting of extracted melts from previous mantle melting in which modified by subduction-derived fluids.