Articles | Volume 367
03 Mar 2015
 | 03 Mar 2015

Sediment budget in the Ucayali River basin, an Andean tributary of the Amazon River

W. Santini, J.-M. Martinez, R. Espinoza-Villar, G. Cochonneau, P. Vauchel, J.-S. Moquet, P. Baby, J.-C. Espinoza, W. Lavado, J. Carranza, and J.-L. Guyot

Keywords: Ucayali, Pachitea, Andes, Amazon, erosion, sedimentation, MODIS, Peru, hydrology

Abstract. Formation of mountain ranges results from complex coupling between lithospheric deformation, mechanisms linked to subduction and surface processes: weathering, erosion, and climate. Today, erosion of the eastern Andean cordillera and sub-Andean foothills supplies over 99% of the sediment load passing through the Amazon Basin. Denudation rates in the upper Ucayali basin are rapid, favoured by a marked seasonality in this region and extreme precipitation cells above sedimentary strata, uplifted during Neogene times by a still active sub-Andean tectonic thrust. Around 40% of those sediments are trapped in the Ucayali retro-foreland basin system. Recent advances in remote sensing for Amazonian large rivers now allow us to complete the ground hydrological data. In this work, we propose a first estimation of the erosion and sedimentation budget of the Ucayali River catchment, based on spatial and conventional HYBAM Observatory network.