Drainage network development in the Pannonian basin

Abstract

The evolution and development of the greatest rivers in the Pannonian Basin have been investigated for almost 150 years. At the end of the Late Miocene Sub-Epoch (7.5–5.3 Ma BP) and at the beginning of Pliocene Epoch (5.3–4.5 Ma BP) Lake Pannon shrank dramatically, fi lled up with sediments and completely dried up as a result of global climate change (Bérbaltavárian /Messinian/ Stage). In the basin dominated by dry climate conditions, torrents bordered with riparian forests appeared. During the Lower Pannonian Stage (Eppelsheimium in the Hungarian terminology) the tropic rainforests which previously had covered even regions at higher latitudes contracted to a smaller area around the Equator due to the global climate change. Then under the warm and humid climate of the Middle and Late Pliocene (Csarnotanian and Ruscinian Stages, 4–3 Ma BP) tropic rainforests expanded again and the drainage network development of the Pannonian Basin continuing even today started. During our research, climate-indicating travertine layers covering the terraces, travertine stratigraphy and fauna fi ndings were investigated.