GlaciDat – a GIS database of submarine glacial landforms and sediments in the Arctic

Data from two surveys by multi-beam sonar and two by marine/terrestrial LiDAR are used to evaluate the geomorphology of the seafloor in littoral areas of the Canadian Arctic Channels, near King William Island, Nunavut. Submarine terrains show well-preserved glacial landforms (drumlins, mega-scale glacial lineations, iceberg-turbated terrain, recessional moraines, and glaciofluvial landforms) with only slight modification by modern processes (wave action and sea-ice activity). At Gjoa Haven the seafloor is imprinted by fields of pits 2 m wide and 0.15 m deep. They may result from gas hydrate dissolution triggered by falling relative sea levels. The Arctic Archipelago displays what might be termed inverted terrains: marine terrains, chiefly beach ridge complexes, exist above modern sea level and well-preserved glacial terrains are present below modern sea level. This is the inverse of the submerging regimes of Atlantic Canada, where glacial terrains exist on land, but below sea level they have been effaced and modified by marine processes down to the lowstand depth.

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New results on the dynamics of the NW part of the Svalbard Ice Sheet during the deglaciation of the Woodfjorden Trough

10.5194/egusphere-egu2020-10921 ◽

2020 ◽

Author(s):

Tom Arne Rydningen ◽

Amando Lasabuda ◽

Jan Sverre Laberg ◽

Christine Tømmervik Kollsgård ◽

Stine Bjordal Olsen ◽

...

Keyword(s):

Continental Shelf ◽

Ice Sheet ◽

Outer Part ◽

Middle Part ◽

The Arctic ◽

Quality Data ◽

Glacier Front ◽

Ice Retreat ◽

Late Weichselian ◽

Glacial Landforms

Present-day warming is most pronounced at high latitudes, raising concern for the stability of modern ice caps such as the ones overlying the Svalbard archipelago. Palaeo-records give us opportunity to understand past behavior of these systems, including the ice retreat from the continental shelf at the end of the last glaciation. In order to evaluate and reconstruct this in a robust way, it is essential that we acquire high-quality data sets covering key areas in the Arctic.New multi-beam bathymetric data was acquired in July 2019 from the Woodfjorden Trough; an up to 60 km long and 40 km wide transverse trough on the northwestern part of the Svalbard continental shelf. Previous investigations have shown that this trough was occupied by a major ice stream draining the Svalbard Ice Sheet during the last glacial, but the deglacial dynamics of this sector of the Svalbard Ice Sheet are presently not well constrained.The new data reveal a complex seabed morphology including larger (2 km wide, 50 m high) and smaller (100 m wide, 3 m high) ridges, as well as sediment wedges (1 to 2 km wide, 30 m high), partly showing crosscutting relationships. These ridges and wedges are discontinuous in the outer part of the trough, where they are partly superposed by glacial lineations and small- to larger sized iceberg ploughmarks (up to 1500 m wide and 30 m deep). In the middle part of the trough, more continuous ridges dominate.The ridges and wedges are interpreted to be glacial landforms formed by grounded ice within the Woodfjorden Trough. Their crosscutting relationships testify to a complex deglaciation, including several advances and still stands of the ice front during overall ice retreat, and their size could indicate that the glacier front was stable for some time. Smaller ridges may be retreat moraines formed during shorter (annual?) still stands of the glacier front. Based on their discontinuous characteristics, the ridges and wedges in the outer part of the trough may pre-date the final Late Weichselian deglaciation, i.e. they may have been overridden by a grounded glacier. The more continuous character of the ridges in the middle part of the trough indicate that these likely date from the Late Weichselian deglaciation.The glacial landforms identified here are rather atypical for glacial troughs, commonly dominated by mega-scale glacial lineations superposed by one or a few grounding zone wedges and/or smaller retreat moraines. The abundant morainal systems and glacial lineations of the Woodfjorden Trough, instead, testify to highly dynamic grounded ice occupying the trough, and a retreat which was characterized by several periods of ice margin stability, interrupted by readvances. This fits with recent studies from onshore areas, showing that the deglaciation of northern Svalbard was at least partly characterized by glacial readvances during the overall ice retreat.

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BRITICE Glacial Map, version 2: a map and GIS database of glacial landforms of the last British-Irish Ice Sheet

Boreas ◽

10.1111/bor.12273 ◽

2017 ◽

Vol 47 (1) ◽

pp. 11-e8 ◽

Cited By ~ 44

Author(s):

Chris D. Clark ◽

Jeremy C. Ely ◽

Sarah L. Greenwood ◽

Anna L. C. Hughes ◽

Robert Meehan ◽

...

Keyword(s):

Ice Sheet ◽

Gis Database ◽

Glacial Landforms

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The De Long Trough: a newly discovered glacial trough on the East Siberian continental margin

Climate of the Past ◽

10.5194/cp-13-1269-2017 ◽

2017 ◽

Vol 13 (9) ◽

pp. 1269-1284 ◽

Cited By ~ 8

Author(s):

Matt O'Regan ◽

Jan Backman ◽

Natalia Barrientos ◽

Thomas M. Cronin ◽

Laura Gemery ◽

...

Keyword(s):

Continental Shelf ◽

Arctic Ocean ◽

Ice Sheets ◽

Laminated Sediments ◽

The Arctic ◽

Outer Continental Shelf ◽

Last Glacial ◽

Glacial Landforms ◽

Siberian Shelf ◽

The Last Glacial

Abstract. Ice sheets extending over parts of the East Siberian continental shelf have been proposed for the last glacial period and during the larger Pleistocene glaciations. The sparse data available over this sector of the Arctic Ocean have left the timing, extent and even existence of these ice sheets largely unresolved. Here we present new geophysical mapping and sediment coring data from the East Siberian shelf and slope collected during the 2014 SWERUS-C3 expedition (SWERUS-C3: Swedish – Russian – US Arctic Ocean Investigation of Climate-Cryosphere-Carbon Interactions). The multibeam bathymetry and chirp sub-bottom profiles reveal a set of glacial landforms that include grounding zone formations along the outer continental shelf, seaward of which lies a >  65 m thick sequence of glacio-genic debris flows. The glacial landforms are interpreted to lie at the seaward end of a glacial trough – the first to be reported on the East Siberian margin, here referred to as the De Long Trough because of its location due north of the De Long Islands. Stratigraphy and dating of sediment cores show that a drape of acoustically laminated sediments covering the glacial deposits is older than ∼ 50 cal kyr BP. This provides direct evidence for extensive glacial activity on the Siberian shelf that predates the Last Glacial Maximum and most likely occurred during the Saalian (Marine Isotope Stage (MIS) 6).

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Oriented lake-and-ridge assemblages of the Arctic coastal plains: glacial landforms modified by thermokarst and solifluction

Polar Record ◽

10.1017/s0032247400015503 ◽

1999 ◽

Vol 35 (194) ◽

pp. 215-230 ◽

Cited By ~ 15

Author(s):

Mikhail G. Grosswald ◽

Terence J. Hughes ◽

Norman P. Lasca

Keyword(s):

Ice Sheet ◽

Late Glacial ◽

The Arctic ◽

Laurentide Ice Sheet ◽

Baffin Island ◽

Mackenzie Delta ◽

Space Images ◽

The North ◽

Arctic Ice ◽

Glacial Landforms

AbstractOriented assemblages of parallel ridges and elongated lakes are widespread on the coastal lowlands of northeast Eurasia and Arctic North America, in particular, in Alaska, Arctic Canada, and northeast Siberia. So far, only the oriented lakes have been of much scientific interest. They are believed to be formed by thermokarst in perennially frozen ice-rich sediments, while their orientation is accounted for either by impact of modern winds blowing at right angles to long axes of the lakes (when it concerns individual lakes), or by the influence of underlying bedrock structures (in the case of longitudinal and transverse alignment of lake clusters).En masseexamination of space images suggests that oriented lake-and-ridge assemblages, not the oriented lakes alone, occur in the Arctic. Hence any theory about their formation should account for the origin and orientation of the assemblages as a whole. The existing hypotheses appear inadequate for this end, so this paper proposes that the assemblages were initially created by glacial activity, that is, by ice sheets that drumlinized and tectonized their beds, as well as by sub- and proglacial meltwater, and then they were modified by thermokarst, solifluction, and aeolian processes. This assumption opens up an avenue by which all known features of oriented landforms in the Arctic can be explained. The paper suggests that the oriented landforms in Siberia and Alaska are largely signatures of a marine Arctic ice sheet that transgressed from the north, while the Baffin Island and Mackenzie Delta forms were created by the respective sectors of the Laurentide ice sheet. The oriented features discussed belong to the last Late Glacial through the Early Holocene.

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Map and GIS database of glacial landforms and features related to the last British Ice Sheet

Boreas ◽

10.1080/03009480410001983 ◽

2004 ◽

Vol 33 (4) ◽

pp. 359-375 ◽

Cited By ~ 174

Author(s):

Chris Clark ◽

David Evans ◽

Anjana Khatwa ◽

Tom Bradwell ◽

Colm Jordan ◽

...

Keyword(s):

Ice Sheet ◽

Gis Database ◽

Glacial Landforms

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High‐resolution bathymetric mapping reveals subaqueous glacial landforms in the Arctic alpine lake Tarfala, Sweden

Journal of Quaternary Science ◽

10.1002/jqs.3112 ◽

2019 ◽

Vol 34 (6) ◽

pp. 452-462

Author(s):

Nina Kirchner ◽

Riko Noormets ◽

Jakob Kuttenkeuler ◽

Elias Strandell Erstorp ◽

Erik Schytt Holmlund ◽

...

Keyword(s):

High Resolution ◽

Alpine Lake ◽

The Arctic ◽

Bathymetric Mapping ◽

Glacial Landforms

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Post-Little Ice Age retreat of glaciers triggered rapid paraglacial landscape transformation in Sørkapp Land (Spitsbergen)

10.5194/egusphere-egu2020-8967 ◽

2020 ◽

Author(s):

Justyna Dudek ◽

Mateusz Czesław Strzelecki

Keyword(s):

Little Ice Age ◽

Remote Sensing Data ◽

Spatial Diversity ◽

Ice Age ◽

The Arctic ◽

Rapid Reduction ◽

Glacier Recession ◽

Landscape Transformation ◽

Glacial Landforms ◽

Marginal Zones

Contemporary climate warming in the Arctic affects the dynamics of the entire environment, including components of the cryosphere: permafrost and glacier systems. The change in the structure of the polar landscape since the termination of the Little Ice Age (ca. 1900) was expressed by widespread retreat of glaciers, progressive exposure of glacial landforms at ice margins and opening ice marginal zones to increasing paraglacial and periglacial processes operating synchronously in adjacent areas.The main aim of the presented study was to determine the course and spatial diversity of landscape transformation in the S&#248;rkapp Land peninsula (Spitsbergen) as a result of glacier recession in the periods 1961-1990-2010 based on existing remote sensing data. Using photogrammetric methods of data processing combined with GIS techniques, the rates of proglacial and ice-marginal terrain change following deglaciation have been determined.For the mentioned research period, the area of the marginal zones almost doubled from 53 km&#178; to 99 km&#178;. The dynamics of landscape transformation in these zones manifested in rapid reduction in the surface elevation of ice-cored moraines (with mean decrease of 0,18-0,22 m per year) and the forms underlain by the dead-ice. This process was enhanced by mass movements and debris flows. Within marginal zones, the area of subglacial landforms and sediments increased by 31 km&#178; from 8 km&#178; in 1961 to 39 km&#178; in 2010.Larger volume of proglacial waters and associated intensification of denudation, transport and accumulation of sediments entailed area increase of sandurs and proglacial riverbeds (which almost tripled from 3,5 km&#178; to over 10 km&#178;). Further redeposition and remobilization of material in some places also promoted enhanced sediment aggradation in coastal environment forming new beaches and spit systems.

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De Long Trough: A newly discovered glacial trough on the East Siberian Continental Margin

10.5194/cp-2017-56 ◽

2017 ◽

Cited By ~ 1

Author(s):

Matt O'Regan ◽

Jan Backman ◽

Natalia Barrientos ◽

Thomas M. Cronin ◽

Gemery Laura ◽

...

Keyword(s):

Continental Shelf ◽

Arctic Ocean ◽

Ice Sheets ◽

Laminated Sediments ◽

The Arctic ◽

Outer Continental Shelf ◽

Last Glacial ◽

Glacial Landforms ◽

Siberian Shelf ◽

The Last Glacial

Abstract. Ice sheets extending over parts of the East Siberian continental shelf have been proposed during the last glacial period, and during the larger Pleistocene glaciations. The sparse data available over this sector of the Arctic Ocean has left the timing, extent and even existence of these ice sheets largely unresolved. Here we present new geophysical mapping and sediment coring data from the East Siberian shelf and slope collected during the 2014 SWERUS-C3 expedition (SWERUS-C3: Swedish – Russian – US Arctic Ocean Investigation of Climate-Cryosphere-Carbon Interactions). The multibeam bathymetry and chirp sub-bottom profiles reveal a set of glacial landforms that include grounding zone formations along the outer continental shelf, seaward of which lies a >65 m thick sequence of glaciogenic debris flows. The glacial landforms are interpreted to lie at the seaward end of a glacial trough – the first to be reported on the East Siberian margin, here referred to as the De Long Trough because of its location due north of the De Long Islands. Stratigraphy and dating of sediment cores show that a drape of acoustically laminated sediments covering the glacial deposits is older than ~50 cal. kyr BP. This provides direct evidence for extensive glacial activity on the Siberian shelf that pre-dates the Last Glacial Maximum and most likely occurred during the Saalian (Marine Isotope Stage [MIS] 6).

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