Linking source and sink in the Rwenzori Mountains and adjacent rift basins, Uganda: Landscape evolution and the sedimentary record of extreme uplift

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The Rwenzori Mountains and adjacent rift flanks represent the highest uplift of rift flanks on Earth and its uplift may have signifiantly contributed to the aridisation of East Africa since the Late Miocene. Within the RIFLE programme this project aims to reconstruct the erosional evolution of the Rwenzori Mountains since their extreme uplift using topographic properties, cosmogenic nuclides (10Be) and alluvial sedi-ments. Based on remote sensing, representative localities of active erosion and exposures of river terraces or the proximal basin fill will be selected for field studies. Suitable outcrops will be studied with respect to sedimentology and fluvial dynamics. Some OSL (optically stimulated lumines-cence) datings will deliver a time frame for the younger alluvial deposits. A highly resolved DEM (30 m) is used to analyse the landscape morphometry of the rift flanks and its dependence on uplift rates, rain-fall distribution, credibility of bedrocks, and denudation rates. Specific attention is paid to identify neotectonic movements. The controlling factors of erosion will be explored by field mapping, GIS analysis and numerical experiments using a suitable computer code of existing surface process models. Finally, the results will be integrated into an evolutionary model of erosion, sediment flux, and rift basin fill for the central western branch of the East African Rift.