Petrology of the Eastern Taurus Ophiolite (Turkey)

There are many ophiolitic massifs, situated either northern or southern flank of the EW-trending Pütürge-Bitlis Metamorphic units, that they inform a good tectono-magmatic model for the Neotethyan ocean during Mesozoic in Taurus Oriental. They are, from west to east, Kızıldag, Koçali, Göksun, İspendere, Guleman and Gevaş. They consist of mantle peridotites, oceanic crust units, such as mafic cumulats, isotropic gabbros, sheeted dyke complex which are covered by the basaltic pillow, massive lavaş, and isolated diabase dykes. Some ophiolitic massifs as Koçali, Göksun, and Gevaş and tectonically overlying metamorphic units were intruded by tonalitic and granodioritic intrusions. The mantle peridotites are generally harzburgite and less lherzolite, mafic rocks consist of layered and isotropic gabbros cutting by wehrlitic intrusions. Geochemical data indicate the presence of two different types of volcanics, MORB and suprasubduction. The age of the volcanic rocks have been assigned to Late Triassic-Upper Cretaceous based on the radiolarian data from the associated pelagic rocks units. On the basis of petrography, geochemistry andage data, we conclude that the evolution of the eastern Taurus ophiolites involved at least two stage episodes. The first stage is presented by MOR type rocks and the second stage is characterized by SSZ type rocks.