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TitleIce-sculpted bedrock in channels of the Canadian Arctic Archipelago
AuthorDowdeswell, J A; Todd, B J; Dowdeswell, E K; Batchelor, C L1E
SourceAtlas of Submarine Glacial Landforms: Modern, Quaternary, and Ancient; Geological Society Memoir vol. 46, 2016 p. 59-60, https://doi.org/10.1144/M46.111
Year2016
Alt SeriesEarth Sciences Sector, Contribution Series 20150043
PublisherGeological Society of London (London)
Documentbook
Lang.English
Mediapaper; on-line; digital
File formatpdf
ProvinceNorthern offshore region
NTS87C; 97D
AreaSmith Sound; Amundsen Gulf; Peel Sound
Lat/Long WENS -74.4194 -74.4139 78.0333 77.9000
Lat/Long WENS-119.0833 -118.5000 69.8500 69.5000
Lat/Long WENS -96.0250 -96.0000 72.8333 72.7833
Subjectsstriations; chattermarks; glacial erosion; bedrock erosion; fine-scale abrasion; p-forms; gouges
Illustrationslocation maps; seismic reflection profiles; bathymetric profiles
ProgramMarine Geohazards, Public Safety Geoscience
AbstractGlaciers erode bedrock at all scales, from striations of millimetres in width through to the landscape-scale of U-shaped valleys and fjords. Glacier erosion processes include fine-scale abrasion and the fracture of larger rock fragments (e.g. Iverson 1990; Harbor 1992). These processes take place especially where high stress concentrations are present below rock particles held at the glacier bed beneath actively flowing ice that is at the pressure melting point. The rate and nature of bedrock erosion by ice is also dependent on the rock type involved, its joint structure at both macro- and micro-scales and the presence of water in any joints and cavities (e.g. Iverson 1991). Multibeam sonar imagery of rocky areas of the high-latitude seafloor often reveals streamlined bedrock landforms although metre-scale and smaller features, such as striations, gouges, chattermarks and p-forms (Dahl 1965; Benn & Evans 2010), are usually below system resolution.
Summary(Plain Language Summary, not published)
Glaciers erode bedrock at all scales, from striations of millimetres in width through to the landscape-scale of valleys and fjords. Glacier erosion processes include fine-scale abrasion and the fracture of larger rock fragments. These processes take place especially where stress concentrations below rock particles held in the ice are high beneath actively flowing basal ice that is at the pressure melting point. The rate and nature of bedrock erosion by ice is also dependent on the rock-type involved, its joint structure at both macro- and micro-scales, and the presence of water in any joints and cavities. Multibeam imagery of rocky areas of the high-latitude seafloor often reveals streamlined bedrock landforms, although metre-scale and smaller features, such as striations, gouges, chattermarks and p-forms, are usually below system resolution.
GEOSCAN ID296403