Ptolemaïs basin: The tectonic origin of a Senonian marine basin underneath the southeastern Mediterranean Sea

The large Litani anticline, that was recently discovered in the SE Mediterranean basin, sheds new light on the regional tectonic history of the Levant in the late Cretaceous. The anticline is buried under 5 km of undeformed sedimentary series, its apex was leveled by erosion, and its folding can be dated to the early Senonian. The seismic reflection data suggest that shortly after the structural development of the anticline in a shallow marine environment and under compressional stresses, the regional tectonic regime turned extensional, and the anticline subsided into the open marine environment of Ptolemaïs basin. That subsidence can be dated to the Senonian as well. It is suggested that the Litani anticline is a part of the Syrian Arc, and its deformation and subsequence subsidence reflect the complex tectonic regime of southern Anatolia, where the continental collision with Arabia and the subduction of the Neo-Tethys oceanic crust took place concurrently. The Litani anticline and the Ptolemaïs basin thus show that contrasting tectonic regimes and their structural derivatives could evolve at a very fast rate.