GSA QUATERNARY GEOLOGY AND GEOMORPHOLOGY DIVISION FAROUK EL-BAZ AWARD FOR DESERT RESEARCH 2020: A NEW LOOK AT THE KALAHARI GROUP SEDIMENTS
Results also imply a less arid early-mid-Pleistocene environment than the present in southern Africa, and major reorganization of drainage systems. For example, our data establish the existence of a shallow water body that persisted for >450ka prior to 1.2Ma. Evidence from neighbouring archaeological excavations suggests an association of high-density hominin occupation with this water body.
Independently, the residence time of the Kalahari sand blanket, that covers large parts of the basin, is determined applying a cosmogenic isotope-based model. Results indicate that throughout the Kalahari, sand penetrated and covered the basin 1-2 Ma and that since 1Ma the Kalahari sand cover has been mostly stable.
Overall, the new examination of the KGS implies a dynamic landscape in which cycles of aggradation-erosion occurred, but only the last one is preserved in the sedimentary record. The dominance of aeolian activity in the last 1 Ma is the result of the overall aridification in southern Africa.