EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Mid-Pleistocene volcano-tectonic fragmentation of the Turkana-Suguta Megalake

Annett Junginger1,2, Simon Kuebler3, Carolina Rosca1, R. Bernhard Owen4, Alan Deino5, Craig Feibel6, Martin. H. Trauth7, and Hubert Vonhof8
Annett Junginger et al.
  • 1Department of Geosciences, Eberhard Karls University Tuebingen, Tuebingen, Germany
  • 2Senckenberg Center for Human Evolution and Paleoenvironment (S-HEP), Tuebingen, Germany
  • 3Department of Earth and Environmental Sciences, University of Munich, Munich, Germany
  • 4Department of Geography, Hong Kong Baptist University, Hong Kong
  • 5Berkeley Geochronology Center, Berkeley, USA
  • 6Department of Anthropology, Rutgers University, USA
  • 7Institute of Geosciences, University of Potsdam, Potsdam, Germany
  • 8Max Planck Institute of Chemistry, Mainz, Germany

The East African Rift System (EARS) is a key location for studying Plio-Pleistocene paleoclimate and hominin inhabitance. The region experienced profound reorganization during this interval as a response to volcanism, tectonics and climate change, and arguably detailed spatiotemporally coherent climate datasets could provide evidence of causal links between geologic change and hominin evolution.  However, continued tectonism, erosion, burial and volcanism obscures much of this information. Despite its rich fossil record, the Turkana basin in the northern Kenya Rift is no exception. It has been hypothesized that Lake Turkana and paleo-Lake Suguta to its south formed one 530-650 km long mega-lake before 221 ka ago, and was a major barrier for E-W dispersal of hominids and other terrestrial fauna. Here we present new information on basin development based on paleolandscape modeling and 87Sr/86Sr analysis on microfossils of newly discovered paleo-lake sequences in the Suguta Valley, permitting reconstruction of volcano-tectonic processes 900-700 ka ago. Contrary to previous assumptions, results suggest that two to three lakes separated by tectono-volcanic barriers formed instead of one mega-lake. These results have implications for previously formulated hypotheses about mega-lakes preventing W-E migration and exchange and suggest that during the early Middle Pleistocene E-W migrations were possible.

How to cite: Junginger, A., Kuebler, S., Rosca, C., Owen, R. B., Deino, A., Feibel, C., Trauth, M. H., and Vonhof, H.: Mid-Pleistocene volcano-tectonic fragmentation of the Turkana-Suguta Megalake, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-17267,, 2023.