The Pozanti-Karsanti Ophiolite Complex is situated in the eastern Tauride Belt and represents a remnant of the Mesozoic Neotethyan Ocean. It consists of three distinct nappes: (1) an ophiolitic mélange; (2) a metamorphic sole; and (3) ophiolitic rocks. The oceanic lithosphere section of the Pozanti-Karsanti Ophiolite comprises mantle tectonites, ultramafic-mafic cumulates, isotropic gabbros, sheeted dykes and basaltic volcanic rocks. These units are cut by isolated microgabbro-diabase dykes at all structural levels. New results are presented on the whole-rock and mineral chemistry of the gabbroic cumulates. Well-layered, low-Ti gabbroic cumulates, showing adcumulate to mesocumulate textures, are represented exclusively by gabbronorites. The mineral chemistry of gabbronorites from the Pozanti-Karsanti Ophiolite indicates that these cumulate rocks have been produced by the low-pressure crystal fractionation of basaltic liquid. Magnesium numbers (Mg-numbers) of clinopyroxene, orthopyroxene and amphibole range from 89 to 73, 80–66 and 80–72, respectively. Plagioclase compositions range from An94 to An84. The coexistence of calcic plagioclase, magnesian clinopyroxene and orthopyroxene indicates that the cumulate gabbronorites from the Pozanti-Karsanti Ophiolite were formed in an arc environment. The covariation of Al2O3 and Mg-numbers of both clinopyroxene and orthopyroxene show features typical of low-pressure igneous intrusions such as the Skaergaard and Tonsina Complexes, but differ from the high-pressure ultramafic cumulates found in the same arc. The cumulate gabbronorites probably represent shallower levels in the arc which were subsequently juxtaposed against deeper level ultramafic cumulates either during accretion or later faulting.

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A number of Late Cretaceous ophiolitic bodies are located between the metamorphic massifs of the southeast Anatolian orogenic system. One of them, the Göksun ophiolite (northern Kahramanmaraş), which crops out in a tectonic window bounded by the Malatya metamorphic units on both the north and south, is located in the EW-trending nappe zone of the southeast Anatolian orogenic belt between Göksun and Afşin (northern Kahramanmaraş). It consists of ultramafic–mafic cumulates, isotropic gabbro, a sheeted dyke complex, plagiogranite, volcanic rocks and associated volcanosedimentary units. The ophiolitic rocks and the tectonically overlying Malatya–Keban metamorphic units were intruded by syn-collisional granitoids (∼ 85 Ma). The volcanic units are characterized by a wide spectrum of rocks ranging in composition from basalt to rhyolite. The sheeted dykes consist of diabase and microdiorite, whereas the isotropic gabbros consist of gabbro, diorite and quartzdiorite. The magmatic rocks in the Göksun ophiolite are part of a co-magmatic differentiated series of subalkaline tholeiites. Selective enrichment of some LIL elements (Rb, Ba, K, Sr and Th) and depletion of the HFS elements (Nb, Ta, Ti, Zr) relative to N-MORB are the main features of the upper crustal rocks. The presence of negative anomalies for Ta, Nb, Ti, the ratios of selected trace elements (Nb/Th, Th/Yb, Ta/Yb) and normalized REE patterns all are indicative of a subduction-related environment. All the geochemical evidence both from the volcanic rocks and the deeper levels (sheeted dykes and isotropic gabbro) show that the Göksun ophiolite formed during the mature stage of a suprasubduction zone (SSZ) tectonic setting in the southern branch of the Neotethyan ocean between the Malatya–Keban platform to the north and the Arabian platform to the south during Late Cretaceous times. Geological, geochronological and petrological data on the Göksun ophiolite and the Baskil magmatic arc suggest that there were two subduction zones, the first one dipping beneath the Malatya–Keban platform, generating the Baskil magmatic arc and the second one further south within the ocean basin, generating the Göksun ophiolite in a suprasubduction zone environment.

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