Is gravitational spreading a precursor for the Stífluhólar landslide (Skagafjörður, Northern Iceland)?

Abstract : In Iceland, the Late Weichselian deglaciation led to paraglacial topographic readjustments in the form of extensive deep-seated gravitational slope deformation (DSGSD) and large rockslope failures (landslides and rock-avalanches). Here we provide age estimates for the Stí" uhólar landslide (Tröllaskagi Peninsula, Northern Central Iceland), which indicate that this occurred between the end of the Late Weichselian deglaciation (15-13 ka cal. yr. BP) and 8200 ± 1400 cal. yr. BP. Our surface observations also suggest that the Stífluhólar landslide was probably initiated by propagation and connection of DSGSD failure planes. This observation suggests that the DSGSD can act as a precursor for landsliding in paraglacial settings. However, further investigations are still required to fully assess the role of DSGSD as a landslide precursor, both at the local and at a regional scale. Comparisons with other examples of paraglacial rock slope failures in Northern Iceland and in the world suggest that DSGSD is not the main or suficient precondition for large landslides. The landslide of Stífluhólar occurred due to some combination of favorable preconditioning, predisposing and triggering controls. Predisposing controls include: the favourable dip of the bedding planes in the basaltic bedrock and the presence of intercalated poorly cohesive layers of palagonite between the lava layers, probably acting as basal sliding planes for the landslide.
Type de document :
Article dans une revue
Géomorphologie : relief, processus, environnement, Groupe français de géomorphologie (GFG), 2016, 22 (1), pp.9-24. 〈10.4000/geomorphologie.11295〉
Liste complète des métadonnées

https://hal.archives-ouvertes.fr/hal-01318136
Contributeur : Denis Mercier <>
Soumis le : jeudi 19 mai 2016 - 11:50:14
Dernière modification le : mercredi 11 juillet 2018 - 18:14:02

Identifiants

Citation

Julien Coquin, Denis Mercier, Olivier Bourgeois, Thierry Feuillet, Armelle Decaulne. Is gravitational spreading a precursor for the Stífluhólar landslide (Skagafjörður, Northern Iceland)?. Géomorphologie : relief, processus, environnement, Groupe français de géomorphologie (GFG), 2016, 22 (1), pp.9-24. 〈10.4000/geomorphologie.11295〉. 〈hal-01318136〉

Partager

Métriques

Consultations de la notice

385