%0 Book Section
%9 OS CH : Chapitres d'ouvrages scientifiques
%A Carretier, Sébastien
%A Tolorza, V.
%A Rodríguez, M.P.
%A Pepin, E.
%A Aguilar, G.
%A Regard, V.
%A Martinod, J.
%A Riquelme, R.
%A Bonnet, S.
%A Brichau, Stéphanie
%A Hérail, Gérard
%A Pinto, , L.
%A Farías, M.
%A Charrier, R.
%A Guyot, Jean-Loup
%T Erosion in the Chilean Andes between 27°S and 39°S : tectonic, climatic and geomorphic control
%B Geodynamic processes in the Andes of Central Chile and Argentina
%C Bath
%D 2015
%E Sepúlveda, S.A.
%E Giambiagi, L.B.
%E Moreiras, S.M.
%E Pinto, L.
%E Tunik, M.
%E Hoke, G.D.
%E Farías, M.
%L fdi:010070666
%G ENG
%I The Geological Society of London
%@ 978-1-86239-653-1
%K CHILI ; ANDES
%N 399
%P 401-418
%R 10.1144/SP399.16
%U https://www.documentation.ird.fr/hor/fdi:010070666
%> https://www.documentation.ird.fr/intranet/publi/depot/2017-08-11/010070666.pdf
%W Horizon (IRD)
%X The effect of mean precipitation rate on erosion is debated. Three hypotheses may explain why the current erosion rate and runoff may be spatially uncorrelated: (1) the topography has reached a steady state for which the erosion rate pattern is determined by the uplift rate pattern; (2) the erosion rate only depends weakly on runoff; or (3) the studied catchments are experiencing different transient adjustments to uplift or to climate variations. In the Chilean Andes, between 27°S and 39°S, the mean annual runoff rates increase southwards from 0.01 to 2.6 m a-1 but the catchment averaged rates of decadal erosion (suspended sediment) and millennial erosion (10Be in river sand) peak at c. 0.25 mm a-1 for runoff c. 0.5 m a-1 and then decrease while runoff keeps increasing. Erosion rates increase non-linearly with the slope and weakly with the square root of the runoff. However, sediments trapped in the subduction trench suggest a correlation between the current runoff pattern and erosion over millions of years. The third hypothesis above may explain these different erosion rate patterns; the patterns seem consistent with, although not limited to, a model where the relief and erosion rate have first increased and then decreased in response to a period of uplift, at rates controlled by the mean precipitation rate.
%S Special Publications
%$ 062 ; 068