| Title | Glacial and postglacial landforms and processes adjacent to King William Island, Nunavut, Canadian Arctic Archipelago |
| Download | Download (whole publication) |
| |
| Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
| Author | Shaw, J; Todd, B J |
| Source | Program and abstracts: 2017 GeoHab Conference, Dartmouth, Nova Scotia, Canada; by Todd, B J; Brown, C J; Lacharité, M; Gazzola, V; McCormack, E; Geological Survey of Canada, Open File 8295, 2017 p. 109, https://doi.org/10.4095/305929  Open Access |
| Links | GeoHab 2017
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| Year | 2017 |
| Publisher | Natural Resources Canada |
| Meeting | 2017 GeoHab: Marine Geological and Biological Habitat Mapping; Dartmouth, NS; CA; May 1-4, 2017 |
| Document | open file |
| Lang. | English |
| Media | on-line; digital |
| Related | This publication is contained in Program and abstracts: 2017
GeoHab Conference, Dartmouth, Nova Scotia, Canada |
| File format | pdf |
| Province | Northern offshore region; Nunavut |
| NTS | 57B; 57C; 67A; 67D; 67E |
| Area | King William Island; Canadian Arctic Archipelago; Victoria Strait |
| Lat/Long WENS | -100.0000 -94.5000 70.5000 68.2500 |
| Subjects | marine geology; surficial geology/geomorphology; environmental geology; geophysics; mapping techniques; oceanography; marine environments; coastal studies; conservation; marine organisms; marine
ecology; resource management; biological communities; environmental studies; ecosystems; geophysical surveys; acoustic surveys, marine; sonar surveys; side-scan sonar; postglacial deposits; marine sediments; glacial deposits; glaciomarine deposits;
glacial landforms; glacial features; submarine ridges; drumlins; ice flow; ice movement directions; eskers; iceberg gouging; paleocurrents; paleocurrent directions; glacial history; glaciation; ice retreat; sea level changes; paleo-sea levels;
Wisconsinian glacial stage; seafloor topography; submarine features; channels; bedforms; pockmarks; scour marks; gas seeps; reefs; Laurentide Ice Sheet; Sponges; Biology; Phanerozoic; Cenozoic; Quaternary |
| Program | Offshore Geoscience |
| Released | 2017 09 26 |
| Abstract | The subaerial morphology of coastal King William Island and the bathymetry of adjacent offshore channels of the Canadian Arctic Archipelago have been explored with terrestrial/marine LiDAR and multibeam
sonar surveys. During the Late Wisconsinan, the Laurentide Ice Sheet extended northward across most of the Canadian Arctic and imprinted the buried landscape. Analysis of the survey data elucidates both glacial and postglacial processes that have
shaped the seafloor in channels of the south-central Canadian Arctic Archipelago.
Glacial landforms include multiple, parallel, elongated, ridges many kilometres in length (mega-scale glacial lineations), and fields of drumlins; both of these
features are indicative of ice flow direction, generally to the north. During ice sheet retreat, eskers and tunnel valleys formed beneath the ice and swarms of icebergs were released at the calving front. The keels of numerous icebergs incised the
seabed with a pattern of furrows flanked by berms; these iceberg ploughmarks provide insight into paleocurrent directions in the archipelago during glacial retreat. Iceberg ploughmarks subaerially exposed on King William Island indicate a formerly
higher sea level than at present.
Postglacial landforms include raised beaches on King William Island, formed during the lowering of sea level to its present elevation. Extensive fields of small seabed pockmarks, 2 to 3 m in diameter, were likely
formed by the release of gas within the sea floor sediment. A biogenic or petrogenic source for the gas has yet to be determined. Enigmatic, flat-bottomed pits, about 30 m in diameter, may be strudel scour or may be also related to gas release.
Work is continuing to determine if Hexactinellid sponge reefs populate Victoria Strait west of King William Island. The seabed morphology in Victoria Strait strongly resembles that of sponge reefs mapped in the Pacific Ocean off British Columbia,
where these reefs preferentially grow on ridges of coarse-grained glacial deposits exposed on the seabed. |
| Summary | (Plain Language Summary, not published)
The sixteenth annual GeoHab Conference was held this year (2017) at the Waterfront Campus of the Nova Scotia Community College in Dartmouth, Nova Scotia,
Canada. |
| GEOSCAN ID | 305929 |
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