Variability in depositional processes throughout a 260,000-year lake-sediment archive from Lake Challa (equatorial East Africa) ā€“ a paleoclimate reconstruction based on multi-proxy provenance analysis of the terrigenous fraction

January 2019 to December 2022
climate history
depositional processes
Research fields
Biology and Life Sciences

This project will be undertaken in the framework of the UGent-coordinated international lakedrilling
project ICDP-DeepCHALLA. Drilling operations were successfully carried out in November
2016. The entire sedimentary infill of the lake basin could be retrieved, with excellent recovery and
outstanding quality. The sediments are continuously laminated and provide a unique, undisturbed
and detailed 260,000-year-long sediment record from equatorial East Africa. The proposed project
has two main objectives. Firstly, it will construct the detailed depositional framework of this long
archive, which will help determining how the textural, geochemical and biological information
contained in these sediments should be interpreted. Secondly, detailed examination of particle-size
distributions and their specific end members, mineralogy, geochemistry and isotope geochemistry
of the clastic material brought to the lake by surface runoff and by aeolian processes will allow us to
detect and quantify past changes in its origin and abundance, which reflect changes in lake depth
and the seasonality of rainfall and wind patterns through time. Combined with other sedimentary
proxies of past moisture balance and landscape change, the results of this project will permit a more
coherent, mechanistic understanding of East African climate history during the entire time frame
that modern humans have existed, and inhabited this region.