| Summary: | International audience Nain archipelago is located along the eastern margin of the former Laurentide Ice Sheet (LIS). In this area, successive phases of glacier retreat and readvance have shaped the landscape into fjords and islands. The limited amplitude of the isostatic rebound in the region, compared to southern and western parts under the former Québec-Labrador dome of the LIS, suggest a thinner ice cover during the Last Glacial Maximum (LGM). The geomorphological dynamics of those marine-terminated glaciers stand at the confluence of eustatic, isostatic and topographic driving factors. Following the post-glacial marine transgression, isostatic rebound led to the deposit of successive marine terraces. In order to document the evolution of the archipelago landscape since the LGM, two specific aims will drive this research. Firstly, we set geomorphological maps at different scales including surface formations and processes, through the use of Digital Elevation Models (DEM), detailed satellite imagery, and field survey. Secondly, we establish a detailed chronological frame by the use of three crossed dating methods: cosmogenic nuclides (10 Be, 36 Cl) on bedrock and erratic boulders, luminescence dating (OSL) on sandy deposit, and radiocarbon (14 C) on organic matter and shells. This will allow us to precise the glacial flows directions and heights, deglaciation modalities and driving factors, and the setup of detailed post-glacial emersion curves. This poster presents the methodology and the preliminary results of this PhD research, which is part of the ANR project: "InterArctic : A millenium of interaction between societies and environments in Arctic and sub-Arctic regions".
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