Research

Most large submarine landslides in the North Atlantic are thought to have been triggered during the Pleistocene or immediately following deglaciation. They represent major geohazards since they can break communication cables, subsea pipelines, and oil and gas infrastructures and they can also generate tsunamis (e.g., 1929 Grand Banks earthquake). An understanding of the precise age of landslides  and their stability over time is crucial to correctly assessing geohazards along the western North Atlantic. 

Turbidity currents are gravity flows that transfer large volumes of sediment and organic carbon to the deep-sea and represent major geohazards to offshore infrastructure. The knowledge of where, when and how they occur is of prime importance to mitigate their impact. More importantly, a complete understanding of their impact on the seafloor is critical for the management of seabed infrastructure. Direct monitoring, which includes repeat seabed mapping and the deployment of ADCPs, allows to directly link turbidity currents with changes on the seabed. Direct monitoring of turbidity currents was conducted in Southwind fjord (Baffin Bay) and Pointe-des-Monts (Québec), and is ongoing in Shortland Canyon on the Scotian Slope (eastern Canada).

Following the Last Glacial Maximum (LGM), global ice sheets retreated rapidly, driven largely by melt and retreat of regional-scale ice streams. Eastern Canada was the focus of many large ice streams originating from the Laurentide Ice Sheet. Using multibeam and seismic data combined with sediment cores, ongoing projects aim at reconstructing the maximum extent of marine-based ice and deglaciation of eastern Canada. Main research projects are focused on the Laurentian Channel, Labrador and Baffin Bay.

The distribution of subsea permafrost is largely unknown and relies heavily on modelling that suggests its confinement to the Beaufort, Siberian and Laptev seas. Recently, we have found evidence that subsea permafrost is preserved along the Labrador coast (56ºN) under the influence of the Labrador Coastal Current. Investigation of its formation process and preservation are ongoing. In addition, seabed mapping efforts are underway to better assess the distribution of subsea permafrost elsewhere in subarctic regions where submarine groundwater seepage with a higher freezing point exists.