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Maud Meijers, Utrecht University (Netherlands)
Nuretdin Kaymakci, Middle East Techical University (Turkey)
Cor Langereis, Utrecht University (Netherlands)
Randell Stephenson, Free University (Netherlands)
Douwe Van Hinsbergen, Utrecht University (Netherlands)
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We use paleomagnetism as a powerful tool to quantify the geodynamic evolution of the opening and closure of the Tethys Oceans in the orogenic belt south of the East European Platform. Paleolatitudinal positions for Turkey (Pontides, Taurides) and Ukraine (Crimea) throughout the Mesozoic are determined to constrain the timing and amount of convergence and subduction between these terranes, since motions were mostly north-south directed in the Tethys realm.
The Crimean Peninsula is positioned at the southern edge of Eurasia in Mesozoic times, and we therefore use it as our reference point. The Pontides were separated from the southern margin of Eurasia in the Cretaceous by back-arc spreading, causing opening of the Black Sea. In addition, the Pontides show a northward convex belt caused by large (∼45°) clockwise and anti-clockwise rotations after the late Cretaceous.
The age of sub-ophiolitic metamophics in the Taurides including Central Anatolian Crystalline Complex (CACC) suggest collision of an island arc and ophiolitic obduction onto the Tauride continental block at 90 - 80 Ma. Our new paleomagnetic data, show that there is still ∼1500 km of ocean separating the Pontides and Taurides during the late Cretaceous (∼85 Ma), that was closed at around 50 Ma. This setting and timing is not easily reconciled with current geodynamic models about the Pontide-Tauride system and we discuss alternative scenarios.
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