The possible role of magnetic measurements in the discrimination of Sahara/Sahel dust sources

Auteur(s) et Affiliation(s)



Description :
The mineral magnetic properties of deposited dusts collected along a broadly north-to-south transect across Niger have been investigated on both a bulk and particle size-specific basis. Dusts display a general north-to-south gradient in fine-grained ferrimagnetic mineral (magnetite/maghemite) concentrations, with samples south of the Sahara/Sahel transition, generally containing greater concentrations than dusts from further north where the climate is much drier. This distinction is seen especially clearly in the clay fraction, which harbours the products of weathering and pedogenesis. The AA. suggest that the regional distinction in both dust and surface soil/sand magnetic properties can be related to differences in weathering regime between the arid Saharan parts of the transect and the Sahel sites where higher rainfall has permitted stronger weathering and pedogenesis.


Type de document :
Article de périodique

Source :
Earth surface processes and landforms, issn : 0197-9337, 2012, vol. 37, n°. 6, p. 594-606, nombre de pages : 13, Références bibliographiques : 2 p.

Date :
2012

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