Geology, geochemistry, and evolution of the Divrigi and Kuluncak ophiolitic melanges, with reference to serpentinites in east-central Turkey

The Divrigi and Kuluncak ophiolitic melanges are located in central Anatoli a in the Tauride ophiolite belt. The stratigraphic sequence in the Divrigi ophiolitic melange includes, from bottom to top, the Upper Jurassic-Lower C retaceous Akdag limestone, Upper Cretaceous Calti ultramafic rocks, and the Curek listwaenite. The Divrigi ophiolitic melange is intruded by the Late: Cretaceous-Eocene Murmano pluton. The above stratigraphic sequence is foll owed by the Eocene-Paleocene Ekinbasi metasomatite and the Quaternary Kilis e Formation. The oldest sequence of rocks in Kuluncak ophiolitic melange in the Guvenc a rea is the Karadere serpentine/ultramafic body overlain successively by the Kurtali gabbro, Gundegeikdere radiolarite, the Guvenc listwaenites, and th e Buldudere Formation. The of these units are Lute Cretaceous in age. The K aramagra siderite deposit in the Hekimhan area probably was formed in the L ower Cretaceous at the contact between Calti ultramafic rocks and the Buldu dere Formation. Thr: Kuluncak ophiolitic melange was intruded by a subvolca nic trachyte in the Late Cretaceous. The Eocene-Paleocene Konukdere metasom atite, the Miocene Yamadag volcanic rocks, and Quaternary slops deposits ar e late in the stratigraphic sequence in the Guvenc area. The Kuluncak ophiolitic melange in the Karakuz area is similar to that at G uvenc: however, gabbro, radiolarite, and Miocene volcanic rocks are not pre sent. The Miocene is represented ly the Ciritbelen Formation at Karakuz and the Karakuz iron deposit is hosted by a Late Cretaceous subvolcanic trachy te. The rare-earth and trace-element concentration of serpentinite in the Divri gi and Kuluncak ophiolitic melanges indicate that all of the ultramafics an d their alteration products were derived From a MORB, which was depleted in certain elements and oxides. The results expressed in this study support t he idea that the Divrigi and Kuluncak ophiolitic melanges within the Taurid e ophiolite belt originated from Northern Tauride oceanic lithosphere (Pois son, 1986), instead of a northern branch of Neo-Tethys (Sengor and Yilmaz, 1981).