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Ice Segregation as an Origin for Lenses of Non-Glacial Ice in “Ice-Cemented” Rock Glaciers

  • William J. Wayne (a1)

Abstract

In order to flow with the gradients observed (10° to 15°) rock glaciers cannot be simply ice-cemented rock debris, but probably contain masses or lenses of debris-free ice. The nature and origin of the ice in rock glaciers that are in no way connected to ice glaciers has not been adequately explained. Rock glaciers and talus above them are permeable. Water from snow-melt and rain flows through the lower part of the debris on top of the bedrock floor. In the headward part of a rock glacier, where the total thickness is not great, if this groundwater flow is able to maintain water pressure against the base of an aggrading permafrost, segregation of ice lenses should take place. Ice segregation on a large scale would produce lenses of clear ice of sufficient size to permit the streams or lobes of rock debris to flow with gradients comparable to those of glaciers. It would also account for the substantial loss in volume that takes place when a rock glacier stabilizes and collapses.

Résumé

Pour qu’ils puissent s’écouler sur les pentes où on les observe (10° à 15°), les glaciers rocheux ne peuvent pas être simplement constitués de débris rocheux soudés par la glace, mais contient probablement des blocs ou des lentiiles de glace dépourvus de sédiments. La nature et l’origine de la glace dans les glaciers rocheux, qui ne sont en aucune maniére reliés à des glaciers de glace, n’a pas été correctement expliquée. Les glaciers rocheux et les talus qui les surplombent sont perméables. Les eaux de fusion et de pluie coulent à travers la partie inférteure des blocs sur le bedrock. Dans la partie haute d’un glacier rocheux, lorsque l’épaisseur totale n’est pas grande, si l’écoulement sur le bedrock est suffisant pour maintenir la pression hydrostatique contre la base d’un permafrost en contrepente, il peut y avoir ségrégation de lentilles de glace. La ségrégation de la glace sur une grande échelle produirait des lentilles de glace pure suffisamment importantes pour permettre aux courants et aux langues de débris rocheux de s’écouler sur des pentes comparables à celles des glaciers. Ceci expliquerait aussi la substantielle perte de volume qui intervient lorsqu’un glacier rocheux se stabilise et s’effondre.

Zusammenfassung

Um auf den beobachteten flachen Hangneigungen von 10° bis 15° fliessen zu können, können Blockgletscher nicht einfach eiszementierter Schutt sein, sondern wahrscheinlich Massen oder Linsen schuttfreien Eises enthalten. Die Natur und die Herkunft des Eises in Blockgletschern, die nicht mit Eisgletschern verbunden sind, wurden bisher nicht ausreichend erklärt. Die Blockgletscher und der Schutt auf ihnen sind durchlässig. Wasser aus der Schneeschmelze und Regen fliesst durch den unteren Teil des Schuttes über den Felsuntergrund. Im vorderen Teil eines Blockgletschers, wo die Gesamtdicke nicht gross ist, kann die Absonderung von Eislinsen stattfinden, wenn dieser Grundwasserstrom einen ausreichenden Wasserdruck gegen die Basis eines aufsteigenden Permafrostes aufrecht erhalten kann. Eisabsonderung in grossem Umfang würde Linsen aus klarem Eis erzeugen, deren Grösse die Ströme oder Loben von Felsschutt bei Hangneigungen, die denen von Gletschern vergleichbar sind, zum Fliessen bringen könnten; sie könnte auch den hohen Volumenverlust erklären, der bei unbewegten und kollabierenden Blockgletschern eintritt.

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Copyright

References

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Barsch, D. 1977[a]. Nature and importance of mass-wasting by rock glaciers in Alpine permafrost environments. Earth Surface Processes, Vol. 2, Nos. 23, p. 23145.
Barsch, D. 1977[b]. Ein Permafrostprofil aus Graubünden, Schweizer Alpen. Zeitschrift für Geomorphologie, Neue Folge, Bd. 21, Ht. 1, p. 7986.
Barsch, D. 1978. Active rock glaciers as indicators for discontinuous alpine permafrost. An example from the Swiss Alps. Proceedings of the third International Conference on Permafrost, July 10-13, 1978, Edmonton, Alberta, Canada. Vol. 1. Ottawa, National Research Council of Canada, p. 34853.
Corte, A. E. 1976[a]. The hydrological significance of rock glaciers. Journal of Glaciology, Vol. 17, No. 75, p. 15758. [Letter.]
Corte, A. E. 1976[b]. Rock glaciers. Biuletyn Peryglacjahy, No. 26, p. 17597.
Corte, A. E. 1978. Rock glaciers as permafrost bodies with a debris cover as an active layer. A hydrological approach, Andes of Mendoza, Argentina. Proceedings of the third International Conference on Permafrost, July 10—13, 1978, Edmonton, Alberta, Canada. Vol. 1. Ottawa, National Research Council of Canada, p. 26269.
Corte, A. E., and Blanca, B. 1963. Relationship between four ground patterns, structure of the active layer, and type and distribution of ice in the permafrost. Biuletyn Peryglacjalny, No. 12, p. 790.
Foster, H. L., and Holmes, G. W. 1965. A large transitional rock glacier in the Johnson River area, Alaska Range. U.S. Geological Survey. Professional Paper 525-B, p. B112B116.
Johnson, J. P. jr.. [C 1973.] Some problems in the study of rock glaciers. (In Fahey, B. D., and Thompson, R. D., ed. Research in polar and alpine geomorphology. Proceedings: 3rd Guelph Symposium on Geomorphology, 1973. Norwich, University of East Anglia, Geo Abstracts Ltd.; Guelph, Ontario, University of Guelph, Dept. of Geography, “Geomorphology Symposium”, p. 8494. (University of Guelph. Dept. of Geography. Geographical Publication No. 3.))
Lliboutry, L. A. 1961. Les glaciers enterrés et leur rôle morphologique. Union Géodésique et Géophysique Internationale. Association Internationale d’Hydrologie Scientifique. Assemblée générale de Helsinki, 25—7—6–8 1960. Commission des Nieges et Glaces, p. 272–80. (Publication No. 54 de l’Association Internationale d’Hydrologie Scientifique.)
Luckman, B. H., and Crockett, K. J. 1978. Distribution and characteristics of rock glaciers in the southern part of Jasper National Park, Alberta. Canadian Journal of Earth Sciences, Vol. 15, No. 4, p. 54050.
Mackay, J. R. 1971. The origin of massive icy beds in permafrost, western Arctic coast, Canada. Canadian Journal of Earth Sciences, Vol. 8, No. 4, p. 397422.
Mackay, J. R. 1973. Problems in the origin of massive icy beds, western Arctic, Canada. Permafrost. Second International Conference, 13–28 July 1973, γakutsk, U.S.S.R. North American contribution. Washington, D.C., National Academy of Sciences, p. 22328.
Madole, R. F. 1972. Neoglacial facies in the Colorado Front Range. Arctic and Alpine Research, Vol. 4, No. 2, p. 11930.
Potter, N. jr., 1972. Ice-cored rock glacier, Galena Creek, northern Absaroka Mountains, Wyoming. Geological Society of America. Bulletin, Vol. 83, No. 10, p. 302557.
Smith, H. T. U. 1973. Photogeologic study of periglacial talus glaciers in northwestern Canada. Geografiska Annaler, Vol. 55A, No. 2, p. 6984.
Thompson, W. F. 1962. Preliminary notes on the nature and distribution of rock glaciers relative to true glaciers and other effects of the climate on the ground in North America. Union Géodésique et Géophysique Internationale. Association Internationale d’Hydrologie Scientifique. Commission des Neiges et des Glaces. Colloque d’Obergurgl, 10—9— 18—9 1962, p. 21219. (Publication No 58 de l’Association Internationale d’Hydrologie Scientifique.)
Wahrhaftig, C., and Cox, A. 1959. Rock glaciers in the Alaska Range. Bulletin of the Geological Society of America, Vol. 70, No. 4, p. 383436.
Washburn, A. L. [c 1979.] Geocryology: a survey of periglacial processes and environments. London, Edward Arnold.
Whalley, W. B. 1974. Rock glaciers and their formation as part of a glacier debris-transport system. University of Reading. Dept. of Geography. Geographical Papers, No. 24.
Whalley, W. B. 1976. A rock glacier and its relation to the mass balance of corrie glaciers, Strupbreen, Troms, Norway. Norsk Geografisk Tidsskrift, Bd. 30, Ht. 2, p. 5155.
White, S. E. 1976. Rock glaciers and block fields, review and new data. Quaternary Research, Vol. 6, No. 1, P. 7797.

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