Glacial Sediment Dynamics in North Atlantic Systems

Glacial sediment dynamics in North Atlantic systems encompass the processes by which ice sheets erode underlying bedrock, entrain debris, transport sediment via meltwater streams and icebergs, and ultimately deposit material across fjords, continental shelves and deep basins. During glacial advances, subglacial erosion generates tills and streamlined landforms that record ice flow pathways, while meltwater plumes deliver fine sediments into surrounding basins. Ice-rafted debris (IRD) carried by drifting icebergs creates distinct layers in marine cores that reflect episodic calving and iceberg discharge events. Shifts in sediment depocentres—zones of intense deposition—track ice-margin retreat, revealing rates of ice-sheet stabilisation and rapid reorganisation. Ice shelves and grounding-zone wedges mark former grounding lines and still-stands, preserving evidence of episodic retreat. These sedimentary archives are critical for reconstructing past ice-sheet behaviour, informing predictive models of marine-based ice-sheet response to warming, and understanding impacts on ocean circulation, nutrient fluxes and benthic ecosystems across the North Atlantic realm.

Research from Nature Portfolio

Recent studies have employed extensive radiocarbon-controlled sediment coring in Baffin Bay to map spatio-temporal shifts of sediment depocentres since the Last Glacial Maximum. Results indicate prolonged ice-margin stability on slopes until ~15 ka, followed by rapid landward retreat and a shift of major depocentres onto the inner shelf by ~13–11 ka. Sedimentation-rate-derived erosion estimates highlight high erosion capacity of western Greenland ice streams draining into the bay. Complementary seafloor mapping and seismostratigraphic profiling off northern Baffin Island have revealed a 500 m-thick palaeo-ice shelf during the last glacial episode. This ice shelf influenced the dynamics of Laurentide, Innuitian and Greenland ice streams and its disintegration appears to have triggered large-scale ice-stream reorganisation during early deglaciation.

Glacial Sediment Dynamics in North Atlantic Systems publication trend

The graph below shows the total number of articles in glacial sediment dynamics in north atlantic systems across all publications each year (not limited to Nature Index journals).

Technical terms

Sediment depocentre: A principal zone of sediment accumulation on the seafloor, indicating focused depositional pathways from glacial sources.

Ice-rafted debris (IRD): Coarse sediment fragments transported by icebergs and released into marine environments upon melting.

Grounding-zone wedge (GZW): A sediment accumulation formed at the former grounding line of an ice sheet during pauses in retreat.

Glacimarine sedimentation: Deposition of fine-grained material within marine settings influenced by glacial meltwater and ice proximity.

Ice shelf: A floating extension of a grounded ice sheet that buttresses upstream ice streams and modifies sediment delivery to the shelf edge.

References

1. Shifting sediment depocenters track ice-margin retreat in Baffin Bay. Communications Earth & Environment (2024).
2. Evidence for an extensive ice shelf in northern Baffin Bay during the Last Glacial Maximum. Communications Earth & Environment (2022).
3. Chronology of detrital carbonate events in Baffin Bay reveals different timing but similar average recurrence time of North American-Arctic and Laurentide ice sheet collapse events during MIS 3. Earth and Planetary Science Letters (2023).
4. Enhanced iceberg discharge in the western North Atlantic during all Heinrich events of the last glaciation. Earth and Planetary Science Letters (2021).