Role of the Eastern Mediterranean ophiolites (Turkey, Syria, Cyprus) in the history of the Neo-Tethys

Summary The internal organization and structure of the Taurus, Troodos, Hatay and Baër-Bassit ophiolite massifs are used, along with K-Ar geochronological data for the different parts of the assemblages, to outline stages in the evolution of the Neo-Tethys ocean during Mesozoic times. The authors distinguish: (1) an intra-continental stage, during Middle and Upper Triassic, when alkaline submarine basalts were erupted during rifting of the Arabian platform; (2) a Lower Cretaceous to Campanian phase, marked by active spreading for at least 40 Ma, along east-west trending palaeo-spreading axes, offset by north-south transform fracture zones. During that period, the oldest oceanic lithosphere (Tauride ophiolites and the Baër-Bassit complex) began to be sliced up with the development of metamorphic soles (104 to 88 Ma), later intruded by swarms of tholeiitic diabase dykes of Campanian age (ca. 75 Ma). At that time, the latest spreading zones, now represented by the Troodos and Hatay ophiolites, were still active in the Neo-Tethys; and (3) during the Maastrichtian (70–65 Ma), all ophiolitic massifs were thrust over the Arabo-African continental margin from a single Neo-Tethys oceanic basin.