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Single-grain post-infrared luminescence (SG-pIRIR) protocols allow dating of fluvial deposits that present large scatter in equivalent dose (De) distribution because of heterogeneous bleaching (zeroing) of the grains by sunlight exposure before deposition. In such settings though, luminescence signals measured in modern deposits tend to be better bleached downstream. It suggests that the study of alongstream luminescence signals may allow the quantification of fluvial transport processes and the transient storage of particles in floodplains [1, 4, 5, 6]. In this study, we aim to measure the alongstream distribution of SG-pIRIR signal from modern floodplain deposits of several braided and wandering rivers running in Chile along a latitudinal climatic gradient (Rio Tolten, Rio Allipen, Rio Ñuble, Rio Itata, Rio Choapa, Rio Huasco). Those rivers run from 1000km South of Santiago, where catchments receive up to 2000 mm of annual precipitations, to Huasco in the South of Atacama desert, with precipitations less than 100 mm per year. Measurements of Terrestrial Cosmogenic Nuclide (TCN) 10Be concentrations in modern fluvial sediments indicate a latitudinal gradient in catchment-wide erosion rates from 10² to 10-1 mm/kyr northward [2]. Our catchments of interest are therefore distributed over a distance of more than 2000km between latitudes of 40°S and 28°S, and take place under different climatic conditions, from an oceanic climate in the South to a desertic one in the North, which likely influences the fluvial style of rivers. In this study, we would like to take advantage of this climatic and erosional gradient to investigate further the differences that can occur alongstream in the luminescence signal, and see if we can document different transport parameters along those gradients. Finally, we will combine our luminescence data with state-of-the-art quantification of rates of surface processes by in-situ TCN measurements (10Be, 26Al, 14C and Kr isotopes [3]). [ABSTRACT FROM AUTHOR]