Exploring geochemical controls on weathering and erosion of convex hillslopes : beyond the empirical regolith production function

Auteur(s) et Affiliation(s)



Description :
The AA. develop a model describing steady-state regolith production caused by mineral dissolution on hillslopes which have attained an equilibrium parabolic profile. When the hillslope lowers at a constant rate, the rate of chemical weathering is highest at the ridgetop where curvature is highest and the ridge develops the thickest regolith. This result derives from inclusion of all the terms in the mathematical definition of curvature. Here, the AA. similarly explore model predictions of the effect of curvature at the hillslope scale. The hillslope model shows that when erosion rates are small and vertical porefluid infiltration is moderate, the hill weathers at both ridge and valley in the erosive transport-limited regime. For this regime, the reacting mineral is weathered away before it reaches the land surface. In contrast, when the erosion rate increases or porefluid velocity decreases, denudation occurs in the weathering-limited regime. These predictions are broadly consistent with the observations.


Type de document :
Article de périodique

Source :
Earth surface processes and landforms, issn : 0197-9337, 2013, vol. 38, n°. 15, p. 1793-1807, nombre de pages : 15, Références bibliographiques : 1 p.

Date :
2013

Editeur :
Pays édition : Royaume-Uni, Chichester, Wiley