Horizon / Plein textes La base de ressources documentaires de l'IRD

IRD

Publications des scientifiques de l'IRD

Schwartz S., Zerathe S., Jongmans D., Baillet L., Carcaillet J., Audin Laurence, Dumont T., Bourles D., Braucher R., Lebrouc V. (2017). Cosmic ray exposure dating on the large landslide of Sechilienne (Western Alps) : a synthesis to constrain slope evolution. Geomorphology, 278, 329-344. ISSN 0169-555X

Accès réservé (Intranet IRD) Document en accès réservé (Intranet IRD)

Lien direct chez l'éditeur doi:10.1016/j.geomorph.2016.11.014

Titre
Cosmic ray exposure dating on the large landslide of Sechilienne (Western Alps) : a synthesis to constrain slope evolution
Année de publication2017
Type de documentArticle référencé dans le Web of Science WOS:000392555000024
AuteursSchwartz S., Zerathe S., Jongmans D., Baillet L., Carcaillet J., Audin Laurence, Dumont T., Bourles D., Braucher R., Lebrouc V.
SourceGeomorphology, 2017, 278, p. 329-344. ISSN 0169-555X
RésuméThe 60 x 10(6) m(3) Sechilienne landslide (Belledonne Massif, Western Alps) is located on the right bank of the East-West trending Romanche valley which is shaped by glacial and alluvial processes during the Quaternary. Its head scarp (>35 m high) was dated by Le Roux et al. (2009) using the cosmic ray exposure (CRE) method. Even though these previous results revealed that the initiation of the instability occurred several thousand years after ice down-wastage in the valley, the internal landslide evolution is not constrained. In this paper, we provide 63 additional Be-10 samples collected from the internal scarps and the main scarp, as well as on glacially polished rock surfaces. The aim is to constrain the global landslide kinematics (internal and head scarps) and its relationship with glacier retreat. Results from glacially polished surfaces point out that complex shielding processes (relict moraines, soil deposits and seasonal snow cover) might have affected rock dating. Despite scattering of the resulting ages, the dataset shows that the glacial retreat was achieved between 17.5 and 13 ka. Exposure ages obtained on gravitational scarps reveal that the landslide initiation occurred 8 to 6 ka ago. From the initiation until 2 ka the gravitational kinematics was slow (similar to 2 mm" year(-1)) and focused around the head scarp, leading to a general slope subsidence. After 2 ka, the exposure rates increased significantly (similar to 8 min. year(-1)) with the development of pervasive internal deformation of the landslide mass. This new scenario for the 58chilienne slope reflects a progressive rock-slope weakening since 8 ka, associated with a continuous activity of a deep-seated surface failure.
Plan de classementGéologie et formations superficielles [064]
Descr. géo.FRANCE ; ALPES
LocalisationFonds IRD [F B010068925]
Identifiant IRDfdi:010068925
Lien permanenthttp://www.documentation.ird.fr/hor/fdi:010068925

Export des données

Disponibilité des documents

Télechargment fichier PDF téléchargeable

Lien sur le Web lien chez l'éditeur

Accès réservé en accès réservé

HAL en libre accès sur HAL


Accès aux documents originaux :

Le FDI est labellisé CollEx

Accès direct

Bureau du chercheur

Site de la documentation

Espace intranet IST (accès réservé)

Suivi des publications IRD (accès réservé)

Mentions légales

Services Horizon

Poser une question

Consulter l'aide en ligne

Déposer une publication (accès réservé)

S'abonner au flux RSS

Voir les tableaux chronologiques et thématiques

Centres de documentation

Bondy

Montpellier (centre IRD)

Montpellier (MSE)

Nouméa

Papeete

Niamey

Ouagadougou

Tunis

La Paz

Quito