Submarine geomorphology of the northeastern Baffin Island fiords and cross-shelf troughs

Abstract

This paper presents a series of 50 geomorphological maps of the seabed of northeastern Baffin Island fiords and cross-shelf troughs, in eastern Arctic Canada. The mapping was produced using swath bathymetry imagery from multiple bathymetry datasets. A total of 24 types of landform were systematically mapped (>55,000 landforms) and reflect processes linked to subglacial, ice-marginal or paraglacial to postglacial environments. The landforms record the transition of the seabed from being covered by a marineterminating ice sheet to the establishment of postglacial conditions. The landform assemblages allow the distinction of ice-flows orientation and ice-stream pathways along fiords and cross-shelf troughs. The multiple moraines and grounding-zone wedges indicate that the ice margin stabilized during retreat and that the overall deglaciation occurred by steps. These maps provide a framework for future investigations in northeastern Baffin Island fiords and shelf and can also provide a template for future seabed geomorphological studies in Arctic Canada. ARTICLE HISTORY

Retreat and stabilization of a marine-based ice margin along a high arctic fjord-cross-shelf trough system

“…These extensive elongated ridges are interpreted as ice-stream lateral moraines based on their shape, dimensions and location at the margins of the trough (Ottesen et al, 2007;Rydningen et al, 2013;Batchelor and Dowdeswell, 2016;Brouard and Lajeunesse, 2019b). They have been suggested to be formed mainly from the accumulation of subglacial till at the shear zone between fast-flowing ice stream and slow-flowing portions of an ice sheet or ice free terrain (Dyke and Morris, 1988;Clark, 1999, 2002;Batchelor and Dowdeswell, 2016).…”