| Title | The Prairie dune archipelago |
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| Author | Wolfe, S A |
| Source | Landscapes and landforms of western Canada; by Slaymaker, O (ed.); World Geomorphological Landscapes 2016 p. 167-176, https://doi.org/10.1007/978-3-319-44595-3 12 |
| Image |  |
| Year | 2016 |
| Alt Series | Earth Sciences Sector, Contribution Series 20160300 |
| Publisher | Springer International Publishing |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf (Adobe® Reader®) |
| Province | Alberta; Manitoba; Saskatchewan |
| NTS | 62; 63; 64; 72; 73; 74; 82; 83; 84 |
| Area | Prairie Provinces |
| Lat/Long WENS | -120.0000 -95.0000 60.0000 48.0000 |
| Subjects | surficial geology/geomorphology; environmental geology; Nature and Environment; geophysics; Science and Technology; dunes; dunes, parabolic; depositional history; glacial history; deglaciation; ice
margins; glacial lakes; sediment reworking; morphology; depositional environment; sediment dispersal; dispersal patterns; vegetation; land use; climate; remote sensing; photogrammetric surveys; airphoto interpretation; satellite imagery; Laurentide
Ice Sheet; Cordilleran Ice Sheet; Little Ice Age; Great Plains; Prairies Ecozone; Boreal Plains Ecozone; Boreal Shield Ecozone; Montane Cordillera Ecozone; Taiga Shield Ecozone; Brandon Sand Hills; Elbow Sand Hills; Great Sand Hills; Bigstick Dune
Field; Seward Sand Hills; Middle Sand Hills; Manito Sand Hills; North Battleford Sand Hills; Grande Prairie Dune Field; Holmes Crossing Dune Field; Athabasca Sand Dunes; Glacial Lake Agassiz; Boreal Forest; eolian sediments; dune fields;
glaciofluvial outwash fan sediments; glaciofluvial outwash plain sediments; limit of glaciation; sediment transport directions; Wind; Climate change; Phanerozoic; Cenozoic; Quaternary |
| Illustrations | geoscientific sketch maps; photographs; aerial photographs; satellite images; schematic representations; geophysical images; digital elevation models; drawings |
| Program | GSC Northern Canada Division |
| Released | 2016 12 02 |
| Abstract | The Prairie dune archipelago describes the widely distributed dune fields extending across the Canadian Prairie Provinces. These dune fields have a common origin, with sediment supply derived from sandy
outwash deposits associated with meltwaters of receding Laurentide and Cordilleran glacial ice. Wind reworked sediments soon after deglaciation, in a time-transgressive manner from south to north. Within the boreal forests of western Canada,
post-glacial dune fields are well preserved with little to no remobilization during the Holocene. In contrast, dune fields of the southern Prairies reveal palimpsest landscapes, where dunes were reworked multiple times during the Holocene and
presently display complex morphologies and depositional histories. Whereas relict and partially active stabilized parabolic dunes throughout the Prairies reflect primarily non-arid conditions, evidence exists for desert-like dunes on the southern
Prairies developed during the Little Ice Age, possibly under reduced moisture conditions and shorter growing seasons. Historical accounts of dune fields indicate substantively more active dune fields in previous centuries than at present, raising
issues as to the extent of past disturbances, including drought, fire, trampling and grazing on the activity of sand dunes. The few dune fields with presently active areas have also witnessed significant decline in this century, with a commensurate
loss of plant and animal populations associated with these unique landscapes. |
| Summary | (Plain Language Summary, not published)
The Prairie Dune Archipelago is a unique result of post-glacial meltwater deposition of sand and late Pleistocene to Holocene erosion and redeposition by
wind. The resultant dune fields are widespread, but comparatively small, extending across the vast Canadian Prairies, analogous to an island chain or archipelago in contrast to extensive sand seas. As revealed by complex morphologies and accompanying
chronologies, these dune fields represent some of the most dynamic components of the prairie landscape. Here, dune activity is controlled mainly by sediment availability and wind strength, rather than renewed inputs of sand. Thus, changes affecting
the protective vegetation cover, such as drought and surface disturbances, have been the main drivers of dune activity since deglaciation. The present landscape of the prairie dune archipelago is thus a reflection of complex changes in past wind
regimes, climate and land use. |
| GEOSCAN ID | 299576 |
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