The Fram Slide off Svalbard: a submarine landslide on a low-sedimentation-rate glacial continental margin

Abstract

Submarine slope failures are a widespread, hazardous phenomenon on continental margins. The prevailing opinion links large submarine landslides along the glaciated NW European continental margins to overpressure generated by the alternation of rapidly deposited glacigenic and hemipelagic material. Here, we report a newly discovered large landslide complex off NW Svalbard. It differs from all known large slides off NW Europe, as the available data rule out that this slope failure resulted from rapid glacigenic deposition. This suggests that processes such as contour currents, tectonic faulting, and overpressure build-up related to the gas hydrate system must be considered for hazard assessment.

Chronology of the Fram Slide Complex offshore NW Svalbard and its implications for local and regional slope stability

“…There are not many submarine landslides known and studied in the European Arctic apart from the Hinlopen/Yermak slide complex (Winkelmann and Stein, 2007) and the Fram Slide (Elger et al, 2015). Elger et al (2015) reported on the extent of the Fram Slide and compared it with the typical characteristics of slope failures on the NE Atlantic glaciated margin. That study confirmed that submarine slope failure in the NE…”

The Kongsfjorden Channel System offshore NW Svalbard: downslope sedimentary processes in a contour-current-dominated setting

“…SBF Sjubrebanken Fan Contourite-drift deposition dominated the overall sedimentary environment in the eastern Fram Strait since at least 11 Ma and numerous sediment drifts have been identified on the continental slope off western Svalbard, mainly at water depths exceeding 1200 m [7,21,23,24,41,57,61]. However, multiple escarpments north of the study area provide evidence of repeated downslope sediment transport ( [10,50]). …”

“…Multiple slide scars resulting from large-scale mass wasting occur below 1300-1400 m in the northern part of the study area (Figs. 3, 4e, 5; for details, see [10,50].…”

Submarine Mass Movements and their Consequences

“…Haflidason et al 2004;Baeten et al , 2014Elger et al 2015). Haflidason et al 2004;Baeten et al , 2014Elger et al 2015).…”

“…Slope failures occurred frequently during peak glaciation when grounded ice sheets extended to shelf break and the mouths of glacial shelf troughs (e.g. Baeten et al , 2014Elger et al 2015). However, the rapid deposition of glacigenic debris lobes on fine-grained contouritic deposits with high water content may lead to overpressure in the latter, facilitating the development of large-scale submarine landslides during interglacials (e.g.…”