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  • Icing processes associated with High Arctic perennial springs, Axel Heidelberg Island, Nunavut, Canada
  • Canada ; Cold area ; Conceptual model ; Freezing ; Geochemistry ; Hydrology ; Ice ; Nunavut ; Springs
  • This paper presents preliminary findings of a study concerned with icings and related phenomena associated with perennial springs on Axel Heiberg Island. The icings and frost mounds formed by these springs are very different from those formed
  • by late summer and early winter subglacial discharge. The high solute concentrations lead to freezing-point depression, complex patterns of freezing and the formation of brine icings, together with a variety of mineral precipitates. Freezing-point
  • depression experiments help explain icing hydrology and the spatial pattern of icing formation.
  • Ground-ice stratigraphy and formation at North Head, Tuktoyaktuk Coastlands, Western Arctic Canada : a product of glacier-permafrost interactions
  • Arctic Region ; Canada ; Cold area ; Deglaciation ; Ground ice ; Ice wedge ; Meltwater ; Model ; Northwest Territories ; Periglacial features ; Permafrost ; Stratigraphy ; Wisconsinan
  • Glacially deformed permafrost at North Head, in the Tuktoyaktuk Coastlands, contains a complex ground-ice stratigraphy that formed during the course of the last glacial-interglacial cycle. Two generations of ground ice are distinguished within
  • a single stratigraphic sequence. The superimposition of post-deformation intrusive ice and massive segregated intrusive ice into permafrost containing pre-deformation ground ice indicates that substantial quantitites of overpressurized water were injected
  • into ice-marginal permafrost during or after deglaciation. This required external water was probably overpressurized subpermafrost groundwater in front of the retreating margin of the Late Wisconsinan LIS.
  • 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
  • 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.
  • Recent research in North America supports earlier Russian conclusions about the existence of a transition zone. The transition zone is ice-enriched, and functions as a buffer between the active layer and long-term permafrost by increasing the latent
  • A multidisciplinary study was carried out to understand the interactions between biotic and abiotic processes in granite weathering in ice-free areas of Northern Victoria Land. Examples of tafoni, pits and grooves were analysed, focusing