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Near surface ground ice sediments of the Mackenzie Delta, Northwest Territories, Canada
  • Near surface ground ice sediments of the Mackenzie Delta, Northwest Territories, Canada
  • Active layer ; Canada ; Delta ; Ecology ; Flood ; Ground ice ; Humid environment ; Northwest Territories ; Periglacial features ; Permafrost ; Soil properties ; Vegetation
  • The ice content of near-surface permafrost was determined at more than 70 sites in the Mackenzie Delta. The principal objectives of this paper are : to describe near-surface ground-ice contents for different alluvial terrain types in the Mackenzie
  • Delta; to identify the factors that influence the development of near-surface ground ice; and to examine the influence of ground ice on the flooding hydrology of terrestrial environments in the Mackenzie Delta.
Landforms and ground ice as evidence of the source of H2O in permafrost
  • Landforms and ground ice as evidence of the source of H2O in permafrost
  • This paper summarizes the available evidence for the origin of ice in selected permafrost landforms and in types of ground ice.
Isostatic equilibrium grounding line between the West Antarctic inland ice sheet and the Ross Ice Shelf
  • Isostatic equilibrium grounding line between the West Antarctic inland ice sheet and the Ross Ice Shelf
  • Antarctique ; Barrière de Ross ; Equilibre isostatique ; Glaciologie ; Géographie des régions polaires ; Ligne d'ancrage ; Modèle mathématique ; Modélisation ; Plate-forme continentale ; Ross Ice Shelf
Ground ice in the sedimentary rocks and kimberlites of Yakutia, Russia
  • Ground ice in the sedimentary rocks and kimberlites of Yakutia, Russia
  • Asian part of Russia ; Frost action ; Geochemistry ; Ground ice ; Periglacial features ; Permafrost ; Sakha ; Sedimentary rock
  • in areas of considerable tectonic disturbance. The geochemistry of the ground ice is the result of cryogenic processes that cause salt differentiation during water freezing, together with natural solute concentration and cryogenic mineral formation.
  • The formation of cement (pore) and intrusive ice in the frozen rocks of the central part of the Yakutian diamond-bearing province is considered. Cement ice is best developed in the sedimentary rocks and kimberlite pipes. Intrusive ice is formed only
The burial of ice in the proglacial environment on Bylot Island, Arctic Canada
  • The burial of ice in the proglacial environment on Bylot Island, Arctic Canada
  • Arctic Region ; Canada ; Geophysics ; Glacier fluctuation ; Ground ice ; Ice ; Periglacial features ; Remote sensing ; Thermokarst
  • and permanent snow bank ice are discussed, and specific examples are given from 3 different environments (ice-cored moraines, ice-cored deltas and icings). The impacts of thermokarst and retrogressive thaw flow erosion on the preservation of ground ice are also
  • This paper investigates the occurrence of subsurface ice in a periglacial environment and addresses the potential for its preservation in a high arctic environment such as Bylot Island. The processes associated with the burial of glacial, icing
A computer model along a flow-line of an ice dome: captured ice shelf
  • A computer model along a flow-line of an ice dome: captured ice shelf
  • Floating ice ; Glacial flow ; Glacier mass balance ; Ice ; Numerical model ; Skane ; Sweden
  • The paper examines the captured ice shelf hypothesis through the construction of a numerical model. Based on ice surface elevation, ice thickness, and ground topography, the velocity is calculated. The thickness is adjusted, taking into account
Isotope characterisation of ground ice in northern Canada
  • Isotope characterisation of ground ice in northern Canada
  • Special Issue : Stable isotopes and geochemistry of ground ice
  • Arctic Region ; C 14 dating ; Canada ; Cold area ; Geochemistry ; Ground ice ; Ice wedge ; Isotope analysis ; Oxygen 18 ; Permafrost ; Pingo ; Polar region
  • This paper reviews isotopic research on the characterisation and identification of various types of ground ice throughout the Canadian Arctic, including buried glacier ice, massive segregated ice, segregated ice lenses and offshore ice-rich
  • permafrost, as well as ice related to other cold-region phenomena such as ice wedges, icings (aufeis), frost blisters and pingos. The formational age of ground ice bodies ranges from recent (seasonal ice in the active layer) to tens of thousands of years
  • , when the region experienced widespread continental-scale glaciation. The ratios O 18/O 16 are analysed. Placing the ice bodies into a time frame can be accomplished either through age dating of the enclosing sediments and encased organics, or by direct
  • dating of the ice utilising tritium (3H) for relatively young ice and radiocarbon (14C) analysis of contained gas bubbles for older ice.
Massive ground ice body of glacial origin at Yugorski Peninsula, Arctic Russia
  • Massive ground ice body of glacial origin at Yugorski Peninsula, Arctic Russia
  • Arctic Region ; Ground ice ; Ice ; Oxygen 18 ; Palaeogeography ; Permafrost ; Quaternary ; Russia ; Stratigraphy
  • A massive ground ice body at Cape Shpindler on Yugorski Peninsula, southern Kara Sea coast, Russia, was studied with regard to large-scale internal structures, its stratigraphic context and contacts to surrounding sediments, in order to highlight
  • its origin. The results mean that the buried ice body has survived 2 interglacial periods (Eemian and Holocene), as well as several interstadials. This has consequences for the perception of the potential of relict permafrost to preserve long
Sulfur and carbon isotopes within atmospheric, surface and ground water, snow and ice as indicators of the origin of tabular ground ice in the Russian Arctic
  • Sulfur and carbon isotopes within atmospheric, surface and ground water, snow and ice as indicators of the origin of tabular ground ice in the Russian Arctic
  • Special Issue : Stable isotopes and geochemistry of ground ice
  • Arctic Region ; Coastal environment ; Geochemistry ; Ground ice ; Ice ; Isotope analysis ; Moisture ; Periglacial features ; Russia
  • Field sampling of tabular ground ice (TGI) was undertaken at a number of geological sections along the Russian Arctic coast. S 34 in sulfate ion and C 13 in organic matter were analysed in ground ice and enclosing deposits, and in reference samples
  • structure between TGI and atmospheric and continental moisture. TGI and its enclosing deposits have a heavier isotopic composition of sulfur and carbon than buried snow and glacial ice. This is considered to be evidence of an essential contribution of marine
Origin and characteristics of massive ground ice on Herschel Island (western Canadian Arctic) as revealed by stable water isotope and Hydrochemical signatures
  • Origin and characteristics of massive ground ice on Herschel Island (western Canadian Arctic) as revealed by stable water isotope and Hydrochemical signatures
  • Special Issue : Stable isotopes and geochemistry of ground ice
  • Arctic Region ; Canada ; Cold area ; Deuterium ; Geochemistry ; Ground ice ; Hydrochemistry ; Inland ice ; Isotope analysis ; Oxygen 18 ; Periglacial features ; Permafrost ; Polar region
  • Herschel Island in the southern Beaufort Sea is a push moraine at the northwestern-most limit of the Laurentide Ice Sheet. Stable water isotope (δ18 O, δD) and hydrochemical studies were applied to two tabular massive ground ice bodies to unravel
  • their genetic origin. Buried glacier ice or basal regelation ice was encountered beneath an ice-rich diamicton with strong glaciotectonic deformation structures. Both massive ground ice bodies exhibited a mixed ion composition suggestive of terrestrial waters
  • with a marine influence. Hydrochemical signatures resemble the Herschel Island sediments that are derived from near-shore marine deposits upthrust by the Laurentide ice. A prolonged contact between water feeding the ice bodies and the surrounding sediment
The significance of global snow and ice cover for global change studies
  • The significance of global snow and ice cover for global change studies
  • Climatic warming ; Cryosphere ; Floating ice ; Forecast;Prediction ; Glacial features ; Greenhouse effect ; Ground ice ; Ground survey ; Ice ; Permafrost ; Remote sensing ; Sea ice ; Snow ; Spatial analysis
  • Recent trends of spatial extent and volume of global snow and ice cover are reported the A. examines expected changes projected for increasing concentrations of greenhouse gases too.
The geologic basis for a reconstruction of a grounded ice sheet in McMurdo Sound, Antarctica, at the Last Glacial Maximum
  • The geologic basis for a reconstruction of a grounded ice sheet in McMurdo Sound, Antarctica, at the Last Glacial Maximum
  • Glacial and paleoclimatic history of the Ross ice drainage system of Antarctica. Special issue
  • Aerial photography ; Antarctica ; C 14 dating ; Geochronology ; Glaciology ; Ice sheet ; Lateglacial ; Palaeogeography ; Sea level
  • The overall results in this paper afford a background for interpreting the glacial chronology of eastern Taylor Valley and for reconstructing a grounded ice sheet in the overall Ross Embayment at the Last Glacial Maximum (LGM)
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
Development of covered karstic dolines in ground ice environment (Eastern Alps, Austria). Interests of experimental and mathematical modelling
  • Development of covered karstic dolines in ground ice environment (Eastern Alps, Austria). Interests of experimental and mathematical modelling
  • Alps (The) ; Austria ; Doline ; Ground ice ; Karst ; Meltwater ; Mountain ; Periglacial features ; Permafrost ; Piping
  • The AA. studied the evolution of dolines in ground ice environment, in a paleouvala of the Hochschwab Mts. (Northern Calcareous Alps, Austria) as well as in laboratory conditions. They measured the ground ice thickness by geophysical methods
  • . They estimated the melting (thinning) speed and the pertinent parameters for ground ice samples at different temperatures in laboratory conditions. After simulating the process, the AA. were able to determine the physical conditions generating the ground ice
  • melting phenomena, and based on this they calculated its melting speed. Due to the air circulation in the karst, the lower level of the ground ice starts to melt and the covering sediment particles fall down. Thus the thinned covering sediments will fall
  • -in and dropout dolines will mould the ground, or the surface may sink by the progress of the melting, entailing suffosion dolines to be generated.
Formation of sorted patterned-grounds - a literature review
  • Formation of sorted patterned-grounds - a literature review
  • Classification ; Patterned ground ; Pedogenesis ; Periglacial features ; Soil ; Theory
  • The article presents and compares current views on the development of sorted patterned-grounds in the periglacial zone. The theories can be divided into 8 groups, which assume : 1) convection and/or circulation of the ground en masse ; 2
  • ) circulation of only fine particles of the ground ; 3) convection of pore water ; 4) heave-settlement pulsation and lateral expansion on the fine domains ; 5) cracking of the ground followed by heave-settlement pulsation and lateral expansion of the centres
  • of polygons ; 6) cracking and filling of the fissures by allochthonous coarse material ; 7) gravitational displacement of coarse material due to melting of underlying glacier ice ; and 8) solifluction, linear erosion and/or helical flow. - (BJ)
Cryolithogenesis, the composition and structure of frozen rocks, and ground ice (the current state of the problem)
  • Cryolithogenesis, the composition and structure of frozen rocks, and ground ice (the current state of the problem)
Modelling the dynamics of ice sheets
  • Modelling the dynamics of ice sheets
  • Antarctica ; Cold area ; Glacier dynamics ; Glaciology ; Global change ; Ice sheet ; Model ; Sea level ; Temperature
  • Although the mechanics and qualitative dynamics of grounded ice sheets and ice shelves are fairly well understood, this is not true for the transition between the two. In consequence, the existence and nature of any grounding line instability have
  • yet to be established. Further problems are understanding how uncertainties in input parameters affect results, and obtaining optimal techniques for parameter inference using ice-sheet models.
Extent and chronology of the Ross Sea ice sheet and the Wilson Piedmont Glacier along the Scott Coast at and since the Last Glacial Maximum
  • Extent and chronology of the Ross Sea ice sheet and the Wilson Piedmont Glacier along the Scott Coast at and since the Last Glacial Maximum
  • Glacial and paleoclimatic history of the Ross ice drainage system of Antarctica. Special issue
  • Antarctica ; C 14 dating ; Deglaciation ; Erratic boulder ; Geochronology ; Ice sheet ; Lateglacial ; Palaeogeography ; Quaternary ; Sea level
  • During the Last Glacial Maximum, a coalescent ice mass consisting of the grounded Ross Sea ice sheet and an expanded Wilson Piedmont Glacier covered the southern Scott Coast. Based on marine deposits, features of marine erosion, radiocarbon dates
  • of raised beaches, marine shells, lacustrine algae, most recession of grounded ice in Ross Sea Embayment occurred in mid to late Holocene time, after deglacial sea-level rise due to melting of Northern Hemisphere ice sheets essentially was accomplished
  • . Rising sea level alone could not have driven grounding-line retreat back to the present-day Siple Coast.
Ground-ice stratigraphy and formation at North Head, Tuktoyaktuk Coastlands, Western Arctic Canada : a product of glacier-permafrost interactions
  • 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.
Interannual changes in seasonal ground freezing and near-surface heat flow beneath bottom-fast ice in the near-shore zone, Mackenzie Delta, NWT, Canada
  • Interannual changes in seasonal ground freezing and near-surface heat flow beneath bottom-fast ice in the near-shore zone, Mackenzie Delta, NWT, Canada
  • Canada ; Delta ; Ground freezing ; Ground ice ; Heat flow ; Interannual variability ; Nearshore zone ; Northwest Territories ; Periglacial features ; Permafrost ; Seasonal variability ; Surface temperature ; Water
  • Interannual changes in seasonal ground freezing and near-surface heat flow beneath zones of bottom-fast ice (BFI) were examined over the winters of 2005–06 and 2006–07 within the near-shore zone of the Mackenzie Delta. Winter variability in ground
  • thermal conditions was determined at 3 monitoring sites. When comparing conditions over the two winters, 2005–06 was characterised by a decrease in ice thickness that limited the extent of BFI and seasonal cooling of the ground. These changes in ice
  • conditions had a greater effect on the thermal conditions at sites where water depths were close to the maximum ice thickness. The short ice contact times at these sites are important to the thermal state of permafrost, as only minimal heat exchange