Long-term dispersion of river gravel in a canyon in the Atacama Desert, Central Andes, deduced from their ¹⁰Be concentrations.

ABSTRACT: Intense storms or earthquakes in mountains can supply large amounts of gravel to rivers. Gravel clasts then travel at different rates, with periods of storage and periods of displacement leading to their downstream dispersion over millennia. The rate of this dispersion controls the long-term downcutting rate in mountainous rivers as well as the grain-size signature of climate and tectonic variations in sedimentary basins. Yet, the millennial dispersion rates of gravel are poorly known. Here, we use ¹⁰Be concentrations measured in individual pebbles from a localized source along a 56 km-long canyon in the Central Andes to document the distribution of long-term gravel transit rates. We show that an inverse grain-size velocity relationship previously established from short-term tra

SUBMITTER: Carretier S 

PROVIDER: S-EPMC6882893 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature