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TitreChronology of slope failures in the Fram Slide Complex: Evaluation of the influence of regional processes on slope stability
AuteurElger, J; Bemdt, C; Krastel, S; Gross, S; Piper, D J W; Geissler, W H
SourceMarine Geology 2016., https://doi.org/10.1016/j.margeo.2016.11.003 (Accès ouvert)
Année2016
Séries alt.Secteur des sciences de la Terre, Contribution externe 20150474
ÉditeurElsevier BV
Documentpublication en série
Lang.anglais
DOIhttps://doi.org/10.1016/j.margeo.2016.11.003
Mediapapier; en ligne; numérique
Formatspdf
Lat/Long OENS -9.0000 12.0000 81.0000 78.0000
Sujetsglissements de terrain; coulées boueuses; stabilité des pentes; glissements de pentes; méthane hydraté; hydrate; marges continentales; bathymétrie; sédiments marins; sédiments marins; sédimentologie; géologie marine
Illustrationslocation maps; bathymetric profiles; seismic profiles; tables; geological sketch maps
ProgrammeLa géoscience pour les développements extracôtiers de la côte est, Géoscience en mer
Diffusé2016 12 05
Résumé(disponible en anglais seulement)
The glaciated NW European continental margins are affected by many submarine landslides, which occur predominantly at the front of cross-shelf troughs where the alternation of rapidly deposited glacigenic and hemipelagic material generates sedimentary overpressure. Here, we investigate the influence of local and regional processes such as tectonic activity, changes of climate and oceanography, gas hydrates and fluid migration systems, slope gradient, toe erosion and contourite deposition on slope stability by comparing seismic and bathymetric data of the Fram Slide Complex with data from the tectonically similar Vestnesa area at the northern termination of the Knipovich Ridge approximately 120 km farther south. We show that variation in the local controls has a strong impact on slope stability. Two areas within the Fram Slide Complex underwent different phases of slope failures, whereas there is no evidence at all for major slope failures between the Knipovich Ridge and Vestnesa Ridge farther south. This suggests that slope shape, which influences contour currents and the resulting sedimentation pattern, toe erosion dependent on the throw of normal faults, and the different thickness of contourite deposits exert pronounced effects on slope stability. These results highlight the limitations of regional hazard assessments as small differences in local controlling factors in the region have led to substantially different local slope failure histories.
Résumé(Résumé en langage clair et simple, non publié)
Dans ce document, nous examinons les origines des glissements sous-marins sur une marge continentale à modelé glaciaire analogue à des parties de la marge continentale de l¿Est du Canada. Nous constatons que, à l¿échelle locale, l¿érosion à la base du talus est le facteur ayant la plus grande incidence sur les risques de glissement.
GEOSCAN ID297807