Weathering the escarpment : chemical and physical rates and processes, south-eastern Australia

Auteur(s) et Affiliation(s)



Description :
The passive margin escarpment of south-eastern Australia has a debated but generally accepted model of propagation in which it retreated (within 40 Ma) to near its current position following rifting between Australia and New Zealand 85-100 Ma before present. The AA. focus on this escarpment to quantify chemical weathering rates and processes and how they may provide insight into scarp evolution and retreat. They compare chemical weathering extents and rates above and below the escarpment using a mass balance approach coupling major and trace element analyses with previous measurements of denudation rates using cosmogenic nuclides (10Be and 26Al). They find a slight gradient in saprolite chemical weathering rate as a percentage of total weathering rate across the escarpment. Finally, the AA. quantify variations in the rates and extent of chemical weathering at the hillslope scale across the escarpment to suggest new insight into how climate differences and hillslope topography help drive landscape evolution, potentially overprinting longer term tectonic forcing.


Type de document :
Article de périodique

Source :
Earth surface processes and landforms, issn : 0197-9337, 2009, vol. 34, n°. 6, p. 768-785, nombre de pages : 18, Références bibliographiques : 1,5 p.

Date :
2009

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