7^th International Symposium On Eastern Mediterranean Geology

Mersin ophiolite, which is bounded by the Ecemis fault to the east, the Bolkardag metamorphics to the north, and capped by Miocene carbonates to the west and south, represents a remnant of Mesozoic Neo-Tethyan oceanic crust in Southern Turkey. Except for a sheeted dyke complex, it comprises the following ophiolitic pseudostratigraphy: mantle tectonites, ultramafic-mafic cumulates, basaltic pillow lavas and associated deep marine sediments.

At Sorgun valley (from Sorgun to Erdemli in the western part of the ophiolite body), rock units belonging to the Mersin ophiolite will be given below.

Firstly the tectonic boundary between the ophiolitic mélange and the mantle tectonites are observed at Sorgun Bridge.

Secondly the boundary of the mantle tectonites and cumulates which have over 3 km thickness will be seen in the same valley. The cumulate rocks start with 800 m of ultramafic rocks at the bottom and continue into 2500 m of gabbroic rocks. Ultramafic cumulates consist mainly of dunite, wehrlite and pyroxenite. Igneous lamination, size grading and rhythmic layering are observed as accumulation features in the ultramafic cumulates. Mafic cumulates, mainly of gabbro, leucogabbro, olivine gabbro and anorthosite, constitute more than 2/3 of the whole cumulate section. Size grading and rhythmic layering are also seen in mafic cumulates.

Thirdly the Upper Jurassic-Lower Cretaceous volcanics associated with radiolarites and pelagic limestones will be visited.

At Findikpinari in the middle part of the ophiolite body, the comagmatic basaltic pillow lavas (Upper Cretaceous) of the Mersin ophiolite and the metamorphic sole rocks will be visited.