Paleogeographic evolution and paleoenvironmental reconstruction of the Sudd area during the Early-Mid Holocene, Sudan

Sixty-five diatom species were identified from five localities within the top Umm Ruwaba Formation (namely Bara A, Bara B, Binaya, Sayal and Kosti). The recovered diatoms have been used here to confirm the existence of the so-called Lake Sudd, which once covered parts of central and southern Sudan, and lasted from 5.253 to 11.300 Ka B.P. The diatom assemblage indicates deposition in fresh to slightly saline water. The distribution of large-sized diatoms, noted within the study material, is attributed to the presence of spots characterized by high nutrition which correspond to the beach of the ancient lake. Integration of the paleontological results and remote sensing data permits the delineation of the lake boundary.

Research highlights► Diatom taxa that comprise planktonic and littoral–benthonic forms were recorded. ► The planktonic forms, exclusively reported from Bara, are frequently found in lake. ► The benthonic–littoral forms (noted in mass) correspond to the lake shoreline. ► The diatom taxa indicate the existence of a single lake between 5.253 and 11.300 B.P. ► Paleontological and remote sensing data allow the delineation of the lake shoreline.