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Large sorted stone polygons, and ventifact distribution, in the Syrkadal area, Scania, S. Sweden
  • Large sorted stone polygons, and ventifact distribution, in the Syrkadal area, Scania, S. Sweden
  • Cold area ; Ice wedge ; Periglacial features ; Soil wedge polygon ; Sweden
  • Coin de glace ; Périglaciaire ; Skåne ; Sol polygonal ; Suède ; Zone froide
  • Large sorted polygons in Syrkadal Valley are described. The polygons are interpreted as post-dating the ventifacts of the area, and probably formed during the time span from the deglaciation to the end of Older Dryas (12 050 BP). They were probably
  • reactived during the earlier port of Younger Dryas (11 000-10 500 BP). Factors contributing to the destruction or preservation of relict sorted polygons are discussed.
The Scheme of correlation of polygonal wedge structures
  • The Scheme of correlation of polygonal wedge structures
  • Cryopédologie ; Fente en coin ; Géographie physique ; Géomorphologie ; Périglaciaire ; Sol ; Sol polygonal
Sorted polygons on recently deglaciated terrain in the highland of Mælifellsandur, South Iceland
  • Sorted polygons on recently deglaciated terrain in the highland of Mælifellsandur, South Iceland
  • Cold area ; Deglaciation ; Freeze-thaw cycle ; Freezing ; Iceland ; Moraine ; Soil wedge polygon ; Splash ; Wind
  • Cycle gel-dégel ; Déglaciation ; Gel ; Islande ; Moraine ; Sol polygonal ; Splash ; Vent ; Zone froide
  • This note directs attention to sorted polygons which are rapidly forming on a recently deglaciated ground moraine in the highland of Mælifellssandur, an area where permafrost is absent. It is concluded that in this area the formation oof sorted
  • polygons is connected with cracking of the seasonnaly frozen surface layer combined with rapid infilling of the cracks by sand, gravel, and stones as a result of sorting of surface material due to wind action, rainsplash, drifting snow, and probably also
Frost-fissure patterns in the Nordic countries
  • Climatic geomorphology ; Cold area ; Europe ; Freezing ; Ice wedge ; Northern Europe ; Periglacial features ; Permafrost ; Soil wedge polygon
  • Coin de glace ; Europe ; Europe du Nord ; Gel ; Géomorphologie climatique ; Permafrost ; Périglaciaire ; Sol polygonal ; Zone froide
Ice wedges on hillslopes and landform evolution in the late Quaternary, western Arctic coast, Canada
  • Ice wedges on hillslopes and landform evolution in the late Quaternary, western Arctic coast, Canada
  • Active layer ; Arctic Region ; Canada ; Coastal environment ; Cold area ; Diapir ; Ice wedge ; Permafrost ; Quaternary ; Slope ; Slope gradient ; Soil erosion
  • This paper discusses how hilltop epigenetic wedges can evolve into hillslope anti-syngenetic wedges by prolonged slope denudation. It demonstrates the existence, on hillslopes, of thermally induced mass transport of the active layer from polygon
  • centres, outwards to the throughs and provides survey evidence in support of ice-wedge diapirism. Also it suggests that some discordant hillslope polygon patterns may have developed prior to the evolution of the present topography.
Thermal regime of ice-wedge cracking in Adventdalen, Svalbard
  • Thermal regime of ice-wedge cracking in Adventdalen, Svalbard
  • Arctic Region ; Cold area ; Ice wedge ; Ice wedges ; Periglacial features ; Snow ; Snow cover ; Soil temperature ; Soil wedge polygon ; Svalbard ; Thermal regime
  • Arctique ; Coin de glace ; Fente de gel ; Manteau nival ; Neige ; Périglaciaire ; Régime thermique ; Sol polygonal ; Svalbard ; Température du sol ; Zone froide
  • One year of monitoring (2002-2003) at a low-centred ice-wedge polygon site on Svalbard is described. Ground temperatures were recorded hourly from the top of an ice wedge through the active layer to the ground surface in the central part of a trough
  • and in the adjacent rampart. Daily data on snow-cover depth were collected by automatic digital photography. Cracks were mapped in February, April and July. The results show that cracking occurred after ground temperatures at the centre of the ice-wedge top decreased
  • to below -15°c. Ground cooling in mid-winter occurred mainly through the snow-free ramparts because the ice-wedge troughs were filled by snow to depths of up to 30 cm.
Age determination of fossil ice-wedge polygons in Nordic areas
  • Age determination of fossil ice-wedge polygons in Nordic areas
  • In the Nordic areas there are indications of fossil ice-wedge polygons in the ground surface, e. g. as: (1) a pattern of shallow furrows, (2) crop marks in cultivated areas. The paper intends to give a survey of and to discuss applicable methods
  • for dating the formation or fossilization of such ice-wedge, polygons (shoreline diagrams, C-14 dating or tephrochronology).
Deeply dissected tundra polygons on a glacio-fluvial outwash plain, northern Ungava Peninsula, Québec
  • Deeply dissected tundra polygons on a glacio-fluvial outwash plain, northern Ungava Peninsula, Québec
  • C14 dating ; Canada ; Cold areas ; Cryoturbation ; Fluvioglacial features;Glaciofluvial features ; Glacial features ; Ice wedges ; Periglacial features ; Permafrost ; Quebec ; Soil wedge polygons ; Tundra ; Ungava
  • Canada ; Coin de glace ; Cryoturbation ; Datation C14 ; Fluvioglaciaire ; Glaciaire ; Pergélisol ; Périglaciaire ; Québec ; Sol polygonal ; Toundra ; Ungava ; Zone froide
  • Description des polygones de toundra profondément disséqués de la zone de pergélisol continu de l'extrémité nord de l'Ungava, développés sur une plaine d'épandage fluvio-glaciaire qui s'est formée à la suite de la déglaciation vers 7 500 B.P. Il
  • semble que les fentes de gel occupent encore la partie inférieure des sillons de polygone.
Ice- and soil-wedge dynamics in the Kapp Linné Area, Svalbard, investigated by two- and three-dimensional GPR and ground thermal and acceleration regimes
  • Ice- and soil-wedge dynamics in the Kapp Linné Area, Svalbard, investigated by two- and three-dimensional GPR and ground thermal and acceleration regimes
  • Active layer ; Arctic Region ; Cold area ; Geophysics ; Ice wedge ; Periglacial features ; Permafrost ; Snow cover ; Soil temperature ; Spatial distribution ; Svalbard
  • GPR is applied to image subsurface structures below non-sorted polygons in Kapp Linné, Svalbard, where ice and active-layer soil wedges co-exist within a small area. Two-dimensional GPR images ice wedges as hyperbolic reflections extending down from
  • the frost table. However, some ice-wedge signals are obscured or masked by similar hyperbolic reflections produced by stones or active-layer soil wedges. Three-dimensional GPR images ice wedges as linear amplitude anomalies, which excludes the possibility
  • of misinterpretation and offers more reliable results. GPR investigations show that ice wedges are distributed sporadically in lower (younger) beach ridges, but not in higher (older) ones. Inter-site monitoring of ground temperature, soil moisture, slow ground
  • deformation and cracking during 2004–09 and the determination of near-surface soil texture and stratigraphy suggest that snow cover and soil thermal properties determine the distribution of ice wedges.
Thermally induced movements in ice-wedge polygons, western arctic coast : a long-term study
  • Thermally induced movements in ice-wedge polygons, western arctic coast : a long-term study
  • Active layer ; Arctic Region ; Cold area ; Ice wedges ; Palaeogeography ; Patterned ground ; Periglacial features ; Permafrost ; Soil temperature ; Stratigraphy
  • Etude à long terme des mouvements d'origine thermique dans les polygones à fente de gel sur la côte occidentale de l'Arctique. Mise en évidence d'un faible déplacement estival du mollisol, à différentes profondeurs, dans les sillons de fente de gel
  • gel reliques et lors de l'interprétation de la stratigraphie des polygones.
Thermal-contraction-crack networks as evidence for Late-Pleistocene permafrost in Inner Mongolia, China
  • China ; Cryoturbation ; Ice wedge ; Inner Mongolia ; Palaeo-environment ; Palaeoclimate ; Periglacial features ; Permafrost ; Pleistocene
  • Numerous wedges on the Ordos Plateau show typical characteristics of periglacial sand wedges that enable them to be distinguished from desiccation cracks in clayey illuviation soil horizons. The sand wedges are organized in 2 generations
  • of polygonal networks. The presence of these periglacial phenomena show that the southern limit of continuous permafrost in Inner Mongolia occurred south of 38°N during the Last Glacial Maximum.
Microbial controls on methane fluxes from a polygonal tundra of the Lena Delta, Siberia
  • Microbial controls on methane fluxes from a polygonal tundra of the Lena Delta, Siberia
  • Asian part of Russia ; Delta ; Geochemistry ; Humid environment ; Micro-organism ; Periglacial features ; Permafrost ; Siberia ; Soil wedge polygon ; Tundra
  • Delta ; Géochimie ; Micro-organisme ; Milieu humide ; Méthane ; Pergélisol ; Périglaciaire ; Russie d'Asie ; Sibir' ; Sol polygonal ; Toundra
  • as the quantification of methane production and oxidation under in situ conditions within the active layer of permafrost soils, in a typical polygonal tundra in the Lena Delta, Siberia.
A field perspective on modelling single ridge ice-wedge polygons
  • A field perspective on modelling single ridge ice-wedge polygons
  • Climatic variation ; Cold area ; Ice wedge ; Model ; Numerical model ; Palaeo-environment ; Periglacial features ; Polar region
  • criticisms focus on : the implications of trough evolution for cracking behaviour; the extent to which epigenetic, low-centred polygons represent the population of ice-wedge networks; and the modelled initiation of polygons in drained thaw lakes.
Genesis of active sand-filled polygons in lower and central Beacon Valley, Antarctica
  • Genesis of active sand-filled polygons in lower and central Beacon Valley, Antarctica
  • Antarctica ; Cold area ; Ice wedge ; Patterned ground ; Periglacial features ; Permafrost ; Polar region
  • In this study, the AA. describe and characterise sand-filled wedges and polygons and propose a descriptive model for their formation in lower and central Beacon Valley from detailed analysis of a 2-m resolution aerial photography and other
  • [b1] Dep. of Soil Science, Univ. of Wisconsin, Madison, Etats-Unis
Etude d'une coupe dégagée dans les loess d'Ans (près de Liège). Structures périglaciaires et fentes de gel
  • , and the third after, the formation of the Kesselt soil (Arcy-Stillfried B). Unsorted polygons and earth hummocks have been recognized in loess older than the Arcy-Stillfried B interstadial.
  • The brick-pit at Ans contains evidence for the existence of three nets of ice wedges in the course of the last glaciation. The date of the growth of these ice wedges cannot be determined precisely but it is clear that two developed before
Prospecting frost-wedge pseudomorphs and their polygonal network using the Electromagnetic Induction Sensor EM38DD
  • Prospecting frost-wedge pseudomorphs and their polygonal network using the Electromagnetic Induction Sensor EM38DD
  • Belgium ; Geophysics ; Ice wedge ; Methodology ; Patterned ground ; Periglacial features ; Sedimentary structure
  • The focus of this paper is on locating and mapping frost-wedge pseudomorphs using electromagnetic induction (EMI). The AA. used EMI at a test site in Belgium to develop a new methodology for locating near-surface frost-wedge pseudomorphs. Besides
Zonal peculiarities of polygonal ice-wedge relief in Western Siberia
  • Zonal peculiarities of polygonal ice-wedge relief in Western Siberia
  • Cryopédologie ; Géographie de l'Europe ; Polygone de toundra ; Périglaciaire ; Sibir'Zapadnaja ; URSS d'Asie ; Zone froide
Palaeocryogenic analysis of loess-paleosol sequences
  • Cryoturbation ; Loess ; Palaeogeography ; Palaeosol ; Periglacial features ; Permafrost ; Pleistocene ; Quaternary ; Soil wedge polygon
  • Cryoturbation ; Loess ; Paléogéographie ; Paléosol ; Pergélisol ; Pléistocène ; Périglaciaire ; Quaternaire ; Sol polygonal
Studie van polygonale fossiele structuren in Vlaanderen, op basis van luchfoto's en veldonderzoek
  • Aerial photography ; Belgium ; Flanders ; Geochronology ; Periglacial features ; Photointerpretation ; Soil wedge polygon
  • Belgique ; Géochronologie ; Photo-interprétation ; Photographie aérienne ; Périglaciaire ; Sol polygonal ; Vlaanderen
Ice-wedge casts and relict patterned ground in central Illinois and their environmental significance
  • Ice-wedge casts and relict patterned ground in central Illinois and their environmental significance
  • The objectives of this report are to summarize the data and observations on features and forms that the A. interprets to be the result of the formation of ice wedges and ice-wedge polygons during the last glaciation and to discuss