Palaeogeographic Considerations for Mediterranean and Paratethys Seaways (Oligocene to Miocene)

Abstract

Some considerations on the palaeogeography of the Mediterranean and Paratethys Oligocene to Miocene are presented in ten time-slices. The time-slices start with the vanishing Tethys Ocean in the late Eocene and the birth of two new marine realms at its western end: the Mediterranean Sea and the intercontinental Eurasian Paratethys basin. The time-slices were selected according to general palaeogeographic changes of seaways and arising land bridges for continental migrations. The palaeogeographic sketches were based on Cenozoic plate reconstructions, and the intermediate levels are interpolated accordingly. Strong changes occurred in the history of the Paratethys. From an open ocean in the Eocene with connections to the Polar Sea via the Turgai Strait, it changed to an enclosed basin in the early Oligocene with reduced salinity and endemic faunas. From the middle Oligocene on, the basin opened again, reaching a maximum connection with the Indian Ocean during late Oligocene and early Miocene (late Chattian ‐ early Burdigalian). Intermittent seaways and regional close-off of basins with endemic development characterize the late Burdigalian and middle Miocene. By the mid-Serravallian the final disconnection of the Paratethys occurred, and since Sarmatian time reduced salinity conditions and endemisms prevailed. The Mediterranean was the connecting sea between Indo-Pacific and Atlantic Oceans until the late Burdigalian. With the collision of the Arabian and Anatolian plates in the late Burdigalian, an Eurasian ‐ African landbridge opened for mammal migrations. A short interruption is proposed for the Langhian transgression, followed by a final closure in the Serravallian.