Giant striations at the base of a submarine landslide

Gee, M.J.R.; Gawthorpe, Robert L.; Friedmann, Julio

doi:10.1016/j.margeo.2004.09.003

Cited by 104 publications

(107 citation statements)

References 16 publications

Supporting

Mentioning

101

Contrasting

Order By: Relevance

“…Like other slides (e.g., Gee et al, 2005), the Hinlopen/Yermak Megaslide eroded the underlying and adjacent sediments. Close to its western margin, the slide debris formed an area of generally elevated morphology adjacent to the field of megablocks in the central part.…”

Section: Sophia Basin -Inner Slide Debrismentioning

confidence: 64%

Dynamics and timing of the Hinlopen/Yermak Megaslide north of Spitsbergen, Arctic Ocean

et al. 2008

View full text Add to dashboard Cite

Section: Sophia Basin -Inner Slide Debrismentioning

confidence: 64%

Dynamics and timing of the Hinlopen/Yermak Megaslide north of Spitsbergen, Arctic Ocean

et al. 2008

View full text Add to dashboard Cite

“…The occurrence of numerous submarine landslides has been reported in the literature -some of these slides are small while some are very large such as the Storegga slide in the Norwegian Sea or the Grand Banks slide in offshore Newfoundland. Using advanced technologies, some slide morphologies and potential causes have been explained (Hampton et al 1996;McAdoo 1999;Lee 2000, 2002;Canals et al 2004;Sultan et al 2004;Gee et al 2005;Solheim et al 2005;Krastel et al 2006;Masson et al 2006;Locat et al 2009;Twichell et al 2009;Conway et al 2012) and some risk frameworks have been proposed (Lee and Edwards 1986;Lee et al 1991;Angell et al 2003;Nadim et al 2003Niedoroda et al 2003;Nadim and Locat 2005;Masson et al 2006;Mosher 2009;Lacasse and Nadim 2009). Offshore slopes are typically very mild (<10°, Hadj-Hamou and Kavazanjian 1985).…”

Section: Introductionmentioning

confidence: 99%

Modeling of large-deformation behaviour of marine sensitive clays and its application to submarine slope stability analysis

et al. 2016

View full text Add to dashboard Cite

Post-slide investigations suggest that many large-scale submarine landslides occur through marine sensitive clay layers. A nonlinear mathematical model for post-peak degradation of undrained shear strength of sensitive clay is proposed based on experimental results. A method for estimation of model parameters is presented. Incorporating the model, an analytical solution is developed to examine possible mechanisms of large-scale submarine landslides. Analyses are performed for mild infinite slopes where the failure initiates from a "fully weakened zone" of soil having undrained shear strength lower than the shear stress acting parallel to the slope. The driving force, in excess of resistance, generated from the fully weakened zone is then transferred to the surrounding soil elements resulting in shear band formation due to strain-softening behaviour of sensitive clays. When the length of the fully weakened zone is greater than a critical length, catastrophic shear band propagation (self-driven without any additional external force) occurs, which could result in large-scale offshore landslides. A simple design chart is developed to calculate the critical length. Compared with a 2005 study by Puzrin and Germanovich based on a linear post-peak shear strength degradation model, the present study gives a conservative estimation of critical length for catastrophic shear band propagation.Key words: sensitive clay, large deformation, submarine landslides, shear band, undrained shear strength.Résumé : Les enquêtes post-glissement de terrain suggèrent que de nombreux glissements de terrain sous-marin à grande échelle se produisent à travers les couches d'argiles marines sensibles. Un modèle mathématique non linéaire de la dégradation post-pic de la résistance au cisaillement non drainée de l'argile sensible est proposé sur la base de résultats expérimentaux. Une méthode d'estimation de paramètres du modèle est présentée. Incorporant le modèle, une solution analytique est développée pour examiner les mécanismes possibles de glissements de terrain sous-marin à grande échelle. Les analyses sont effectuées pour des pentes infinies douces où l'échec est entamé à partir d'une « zone totalement affaiblie » du sol ayant une résistance au cisaillement non drainé inférieure à la contrainte de cisaillement agissant parallèlement à la pente. La force d'entraînement, au-delà de la résistance, générée à partir de la zone entièrement affaiblie est transférée aux éléments de sol environnant aboutissant en la formation de bandes de cisaillement en raison du comportement d'adoucissement à la déformation des argiles sensibles. Lorsque la longueur de la zone entièrement affaiblie est supérieure à une longueur critique, une propagation d'une bande de cisaillement catastrophique (auto-conduit sans aucune force externe supplémentaire) se produit qui pourrait entraîner des glissements de terrain en mer à grande échelle. Un graphique de conception simple est développé pour calculer la longueur critique. Par rapport à une étude réalisée e...

show abstract

“…The basal shear surface separates highly stratified in situ slope sediments below from the less stratified, deformed or disrupted reflections comprising the slide body. It may ramp up and down stratigraphy, but will be a smooth surface that may show kinematic indicators (Frey-Martinez et al, 2005;Gee et al, 2005;Moscardelli and Wood, 2008). The top surface is defined as a surface separating the chaotic facies below and the highly stratified facies or slide above.…”

Section: Database and Methodologymentioning

confidence: 99%