Constraining the Timing of the Closure of the Intra‐Pontide Ocean by U–Pb Dating of Syntectonic Calcite

Abstract

The western Black Sea region is a key area for the study of the Neo‐Tethys orogenic belt, as it contains records of the evolutionary history of the entire Alpine orogeny from subduction to oceanic closure and collision. The Izmir‐Ankara and the Intra‐Pontide suture zones represent the final closure of the Neo‐Tethys oceans. However, when the final closure took place is still disputed. In this study, we investigate syn‐collisional faulting events in the western Black Sea region near Istanbul. We performed kinematic analyses of faulting and U–Pb dating of syntectonic calcite precipitates on the fault planes to constrain the timing of Neo‐Tethys Ocean closure and post‐collisional contractional tectonics. Syntectonic calcite precipitates associated with regional N‐S compressional tectonics provide precise U–Pb ages between 48 and 57 Ma, constraining the early Eocene age of reverse faulting and associated closure of the Intra‐Pontide Ocean.