Late-Holocene Mass Movements in High Arctic East Lake, Melville Island (Western Canadian Arctic Archipelago).

• Main Authors: Normandeau, Alexandre, Joyal, Gabriel, Lajeunesse, Patrick, Francus, Pierre, Lamoureux, Scott F., Lapointe, François
• Other Authors: Lamarche, Geoffroy, Mountjoy, Joshu, Bull, Suzanne, Hubble, Tom, Krastel, Sebastian, Lane, Emily, Micallef, Aaron, Moscardelli, Lorena, Mueller, Christof, Pecher, Ingo, Woelz, Susanne
• Format: Book Part
• Language: unknown
• Published: Springer 2016
• Subjects: Canadian High Arctic; mass movements; swath bathymetry; paleoclimate; Arctic; Canadian Arctic Archipelago; Arctic Lake; Cape Bounty; Lake Melville; East Lake; Arctic Archipelago; Melville Island
• Online Access: https://espace.inrs.ca/id/eprint/4000/; https://doi.org/10.1007/978-3-319-20979-1_31

East Lake, located at Cape Bounty (Melville Island, Canadian High Arctic), was mapped using a high-resolution swath bathymetric sonar and a 12 kHz sub-bottom profiler, allowing for the first time the imaging of widespread occurrence of mass movement deposits (MMDs) in a Canadian High Arctic Lake. Mass movements occurred mostly on steep slopes located away from deltaic sedimentation. The marine to lacustrine transition in the sediment favours the generation of mass movements where the underlying massive mud appears to act as a gliding surface for the overlying varved deposits. Based on acoustic stratigraphy, we have identified at least two distinct events that triggered failures in the lake during the last 2000 years. The synchronicity of multiple failures and their widespread distribution suggest a seismic origin that could be related to the nearby Gustaf-Lougheed Arch seismic zone. Further sedimentological investigations on the MMDs are however required to confirm their age and origin.