Submarine slope stability on high-latitude glaciated Svalbard–Barents Sea margin

Dimakis, Panagiotis; Elverhøi, Anders; Höeg, Kaare; Solheim, Anders; Harbitz, C. B.; Laberg, Jan Sverre; Vorren, Tore O.; Marr, Jeff

doi:10.1016/s0025-3227(99)00076-6

Cited by 62 publications

(30 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is crucial for estimating the timescale of the impact on the benthic communities and the possibility that communities would have been able to recover from such a disturbance. However, Dimakis et al [44] estimated that mass wasting on a glaciated continental slope in the northern hemisphere typically occurred at least once every 95 to 170 years. If this is a reliable estimate, and such conditions are applicable to glaciated continental margins elsewhere, the Antarctic slope fauna would have been severely affected during glacial periods, because it might take one hundred to several hundreds of years for the Antarctic benthos to reach community equilibrium following physical destruction [2,5,45,46].…”

Section: Extinction In the Seamentioning

confidence: 99%

On the origin of Antarctic marine benthic community structure

Thatje

Hillenbrand

Larter

2005

Trends in Ecology & Evolution

250

274

View full text Add to dashboard Cite

Section: Extinction In the Seamentioning

confidence: 99%

On the origin of Antarctic marine benthic community structure

Thatje

Hillenbrand

Larter

2005

Trends in Ecology & Evolution

250

274

View full text Add to dashboard Cite

“…The Humboldt Slide, on the northern California continental margin, is interpreted as a large shear-dominated retrogressive slope failure (Gardner et al, 1999). During the last glacial, the Svalbard^Barents Sea Margin was highly instable and generated successive slope failures with a frequency varying between 95 and 170 yr (Dimakis et al, 2000). Also, the Tr×nadjupet Slide, o¡ the coast of Norway, consists of two escarpments and is possibly the product of a progressive Fig.…”

Section: A Multi-phase Instability Event ?mentioning

confidence: 99%

“…the loading of a grounded ice sheet); (3) seepage of shallow methane gases or destabilization of gas hydrates; (4) oversteepening of the margin ; (5) erosion at the toe of the slope ; (6) tectonic setting; and (7) earthquakes (Bugge et al, 1987;Mosher et al, 1994;Mulder and Moran, 1995;Dimakis et al, 2000;Laberg and Vorren, 2000a). Below, we will tentatively evaluate the potential of each of these controlling factors for having triggered the Gebra Slide.…”

Section: Factors Promoting Failurementioning

confidence: 99%

“…with the development of trough^mouth fans . Recent studies on the Bear Island Fan (NE North Atlantic) yielded sediment accumulation rates of up to 60 cm/yr within a 5 km wide ice-proximal zone during the last glacial period (Laberg and Vorren, 1995;Dowdeswell and Siegert, 1999;Dimakis et al, 2000). As a consequence of this extremely rapid loading, the Bear Island Fan underwent severe slope failure (note that these failures occurred during glacial times, in contrast to those of the Gebra Slide).…”

Section: Factors Promoting Failurementioning

confidence: 99%

See 1 more Smart Citation

The Gebra Slide: a submarine slide on the Trinity Peninsula Margin, Antarctica

et al. 2003

View full text Add to dashboard Cite

A large submarine slide^the Gebra Slide^has been discovered on the continental margin of Trinity Peninsula, Central Bransfield Basin, Antarctic Peninsula. The slide scar is clearly expressed in the bathymetry and is cut into the toe of the glacial-period slope-prograding strata on the lower continental slope. Seismic data give evidence of an associated debris-flow deposit embedded in the interglacial-period basin-fill strata of the basin floor. The total volume of sediment involved in the mass movement is about 20 km 3 . Indirect dating of the mass-wasting event, based on seismic^stratigraphic relationships of the slide scar and associated debris-flow deposit with underlying glacial-period slope units and the overlying interglacial-period basin-floor units, suggests that it took place at the transition between the last glacial period and the present-day interglacial. The initiation of the Gebra Slide is attributed to a combination of several factors, such as high sedimentation rates during the last glacial period, the unloading effect of a retreating ice sheet during deglaciation, pre-existing tectonic fabric and high seismicity in the area. This is the first recent submarine slide of this size identified on the glacial, continental margins of Antarctica. In morphology and general characteristics it is quite similar to the well-known large-scale submarine slides from the northern hemisphere glacial margins, although it is smaller. Its most striking characteristic is its lower-slope position (at 1500^2000 m of water depth), which remains up to now difficult to explain. ß

show abstract

“…While some of the researchers used computer programs, such as Slope/W, to accommodate complex geometry and soil profiles, a large number of studies simply assumed infinite slope conditions (Almagor and Wiseman 1991;Mello and Pratson 1999;Dimakis et al 2000;Leynaud et al 2004;Kvalstad et al 2005b;Nixon and Grozic 2007). One of the major limitations of the limit equilibrium method is that it cannot explain the progressive development of a failure surface due to post-peak softening of sensitive clays.…”

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

Submarine slope stability on high-latitude glaciated Svalbard–Barents Sea margin

Cited by 62 publications

References 14 publications

On the origin of Antarctic marine benthic community structure

On the origin of Antarctic marine benthic community structure

The Gebra Slide: a submarine slide on the Trinity Peninsula Margin, Antarctica

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

Contact Info

Product

Resources

About