Les formes et dépôts nivéo-éoliens actuels en Antarctique et au Nouveau-Québec
In Antarctica, McMurdo region, Victoria Valley, niveo-eolian deposits, made of alternating layers of wind driven snow and sand, 0-2 m thick, are perennial. Together with sandy glaciers, they perhaps have some kinship with the layered deposits discovered by Mariner 9 in the south polar region of Mars...
| Published in: | Cahiers de géographie du Québec |
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| Format: | Article in Journal/Newspaper |
| Language: | unknown |
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Consortium Erudit
2005
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| Online Access: | http://www.erudit.org/fr/revues/cgq/1972-v16-n39-cgq2613/021079ar.pdf https://www.erudit.org/fr/revues/cgq/1972-v16-n39-cgq2613/021079ar.pdf https://doi.org/10.7202/021079ar https://core.ac.uk/display/59282647 https://www.erudit.org/fr/revues/cgq/1972-v16-n39-cgq2613/021079ar/ https://www.erudit.org/revue/cgq/1972/v16/n39/021079ar.html?vue=resume http://id.erudit.org/iderudit/021079ar https://academic.microsoft.com/#/detail/2132369840 https://id.erudit.org/iderudit/021079ar |
| Summary: | In Antarctica, McMurdo region, Victoria Valley, niveo-eolian deposits, made of alternating layers of wind driven snow and sand, 0-2 m thick, are perennial. Together with sandy glaciers, they perhaps have some kinship with the layered deposits discovered by Mariner 9 in the south polar region of Mars.In Poste-de-la-Baleine, 55°17' N., 77°46' W., niveo-eolian deposits are annual with the snow melting down every year. They contribute to the nourishment of the first sandy raised beach and of some dunes. On the ice-foot, they form 1, 2 or 3 ephemeral beach-ridges, the highest (1-3 m) being nearest the shore. Mixed ripples of sand and snow form on the fresh snow this pattern is much like that of dune-fields as seen from the air (transverse, reticulate, lobate, etc.) and is much more photogenic than that of sand upon sand, or snow upon snow. According to the relative proportion of snow and sand, their albedo may have every value between that of pure snow and that of pure sand this might be one model, among others, of the variations with time observed in the albedo of the Martian surface. Denivation forms are sharp cones, soft rounded hillocks, the sandy surface of which is typically cracked, sand pellets, sand rolls (denivation micromoraines) and sand nets. Under overhanging impure ice, which forms the base of the niveo-eolian upon the shore-sand, falling droplets of melt-water, when pure, form impact microcraters if saturated with sand, flattened sand pellets if intermediate, sand stalagmites. En Antarctique, région de McMurdo, vallée de Victoria, des dépôts nivéo-éoliens, faits de lits alternants de neige et de sable entraînés par le vent, épais de 0 à 2 m, sont pérennes. Conjointement aux glaciers à sable inclus, ils sont peut-être apparentés aux dépôts stratifiés découverts par Mariner 9 dans la région polaire sud de la planète Mars.À Poste-de-la-Baleine, 55°17' Nord, 77°46' Ouest, les dépôts nivéo-éoliens sont annuels, toute la neige fondant chaque été. Ils contribuent à engraisser la première plage ... |
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