Large-scale rock slope failures in the Eastern Pyrenees : identifying a sparse but significant population in paraglacial and parafluvial contexts

Glacial and paraglacial environments

Auteur(s) et Affiliation(s)



Description :
Large-scale rock slope failures (RSFs) are particularly found in 3 topographic settings in the Eastern Pyrenees : at cirque and trough-head thresholds (transition zones of elevated instability between cirque and main glaciated trough walls); near the upper or outer periphery of the ice field, where glacial adaptation of fluvial valleys is incomplete; and in fluvial valleys beyond glacial limits where incision is locally intense. RSF is absent from the range divide, from within cirques, and from most main valleys. In the montane areas, RSF is strongly associated with vestiges of preglacial summit surfaces, confirming that plateau ridges are less stable than sharpened crests and horns. RSF is contributing significantly to the progressive destruction of this paleic relief. The overall sparsity of RSF indicates insufficient rock mass stresses, including rebound after concentrated bedrock erosion. This may reflect a relatively weak imprint of glacial erosion, in a context of relatively low mean rates of neotectonic uplift, possibly signalling overall that eastern Pyrenees landscapes are close to dynamic equilibrium.


Type de document :
Article de monographie

Source :
Geografiska annaler. Series A. Physical geography, issn : 0435-3676, 2014, vol. 96, n°. 3, p. 357-391, nombre de pages : 35, Références bibliographiques : 4 p.

Date :
2014

Editeur :
Pays édition : Suede, Stockholm, Svenska sällskapet för antropologi och geografi