Pingos are true perennial permafrost mounds. It is generally accepted that there are 2 main types of pingos in terms of genesis : hydrostatic (closed system) and hydraulic (open system). It is here proposed that a third category of polygenetic
(or mixed) pingos should also be recognized. Since suitable conditions for the formation of pure hydrostatic pingos are rarely met outside the Mackenzie Delta/Tuktoyaktuk Peninsula area the world type of pingo is most likely to be of an hydraulic
or polygenetic variety and thus further investigation is warranted, particularly for the elucidation of the palaeoenvironmental inferences of relict pingos.
Première description de pingos en Antarctique. L'absence de cicatrices de pingos dans cette région du globe semble due à la nature du substrat plutôt qu'aux conditions climatiques.
Etude à long terme de la croissance et de l'affaissement des pingos de la péninsule de Tuktoyaktuk. La majorité des 1350 pingos examinés se sont développés dans des fonds de lacs asséchés, sous lesquels se trouvent des dépôts de sable. Les pingos en
expansion sont souvent identifiés par : une rupture en périphérie du pingo, l'écoulement printanier, la croissance des buttes cryogènes, des failles normales et des oscillations de la hauteur du pingo. Certaines données dérivées de l'étude à long terme de la
croissance des pingos sont utiles à l'identification des structures d'affaissement, associées à des paléo-pingos dans des régions actuellement sans pergélisol.
Active layer ; Arctic Region ; Cold area ; Geophysics ; Groundwater ; Ice ; Meltwater ; Periglacial features ; Pingo ; Svalbard
Ground penetrating radar (GPR) investigations conducted on 2 open system pingos, Innerhytte pingo and Riverbed pingo, are described. Surface exposures suggest that both pingos are largely formed in weak Jurassic shales. Little evidence
for the presence of large bodies of massive ice was found. Strong subsurface reflections within the core of both pingos are interpreted as representing either the presence of alternating shale and ice units, or variations in the chemistry, ice crystal properties
or air content of pingo ice. Both pingos are characterized by conspicuous surface icings, with groundwater flow to the surface in late winter, prior to initiation of actve-layer thawing, suggesting derivation from a deep groundwater source.
Arctique scandinave ; Géographie des régions polaires ; Géomorphogenèse ; Permafrost ; Pingo ; Périglaciaire ; Suède ; Zone froide
Description de monticules à noyaux de glaces: des hummocks sont interprétés comme pingos, palses et formes fossiles en formes de mares circulaires. La subsistance de ces formes serait due au climat.
A discussion on pingos in Mellemfjord, Disko, Central West Greenland
Disko ; Eau souterraine ; Fjord ; Groenland ; Géomorphogenèse ; Pergélisol ; Pingo ; Périglaciaire ; Zone froide
Cold area ; Fjord ; Geomorphogenesis ; Greenland ; Groundwater ; Periglacial features ; Permafrost ; Pingo
Open system, or more correctly, hydraulic pingos, are genetically poorly understood. A continuing problem concerns their need for a perennial groundwater supply (intra- or sub-permafrost). This has to be maintained despite the existence
of continuous permafrost in many areas where they are located. Recent work on Disko Iland has suggested a new type of hydraulic pingo developing only in a marsh environment. It is argued that the marsh setting is not relevant to the formation of these features
Location, age and origin of pingo remnants in the Drentsche Aa valley area (the Netherlands)
Datation radiocarbone ; Géographie de l'Europe ; Lithologie ; Palynologie ; Pays-Bas ; Pingo ; Périglaciaire ; Quaternaire zones moyennes
Lithological and palynological data from organic levels below some ramparts suggest growth of most of the pingos in a thaw lake environment. Hydrostatic (closed-system) origin of the pingos is suggested. Radiocarbon data indicate that the pingos
developed between 25,000 and 19,000 BP. Transformation into pingo remnants was not isochronous, but occurred until the middle Late Glacial (Late Weichselian).
Similarities between mounds on Mars and pingos on Earth are considerable; they include the shape, summit craters and occasional circular fractures around some mounds. Pingos probably exist on Mars, but it is difficult to interpret the mounds on Mars
as closed-system pingos because no trace of lakes is visible and the spacing of these mounds is smaller than that of the typical pingos in the Mackenzie delta. The striking similarity between annular ridges on Mars and the depressions surrounded by ramparts
that are remnants of lithalsas in the Hautes-Fagnes (Belgium)suggest a similar origin. Pingos and lithalsas are formed on Earth under different climatic conditions, on Mars they could therefore reflect 2 generations of periglacial mounds and a significant change
Antarctique ; Glace ; Glace du sol ; Géographie des régions polaires ; Géomorphodynamique ; Permafrost ; Pingo
Pingos in Antarctica appear to be residual landforms that have formed on the surface of the moraine as the ice core has been destroyed by ablation and thermal erosion. This interpretation appears to have misinterpreted tension cracks and coherent
slumping of sediment as dilation cracks and as evidence for the extrusion of a central sediment plug. Pingos on supraglacial debris have not been described from any other locations and it seems that their formation is inconsistent with the ablation
Ibryuk Pingo is one of the largest pingos in the world. Precise survey for the 1973 to 1983 period show that the highest peak is growing at a nearly constant rate of 2.3 cm/yr. The source of growth is believed to lie at a depth of about 65 m below
Les cicatrices de pingos sont la marque d'un permafrost ancien ou actuel. Elles apparaissent mêlées aux pingos actifs dans les régions de permafrost actuel. Présentation de formes de convergence liées aux processus glaciaires, thermokarstiques
cicatrices de pingos fossiles antérieures au Wisconsin. (CM).
Groundwater hydrology and stable isotope analysis of an open-system pingo in northwestern Mongolia
Analyse isotopique ; Carotte de glace ; Eau souterraine ; Hydrogéologie ; Mongolie ; Mongolie du Nord-Ouest ; Pergélisol ; Pingo ; Périglaciaire ; Zone froide
Cold area ; Hydrogeology ; Ice core ; Isotope analysis ; Mongolia ; Periglacial features ; Permafrost ; Pingo ; Underground water
Agua subterránea ; Análisis isotópico ; Hidrogeología ; Mongolia ; Muestra de hielo ; Pergelisol ; Periglaciar ; Pingo ; Zona fría
The first record of stable isotopes through a complete sequence of ice within an open-system pingo in northwestern Mongolia indicates a complex history of ice formation and pingo growth. A continuous section of ice 32 m long was cored through
the centre of Mongot Pingo, and ice cores were analysed for stable isotopes and chemical composition. Two different stable isotope patterns in separate ice sections are identified : 1) open-system freezing and 2) semi-closed system (or closed system) freezing
. Discharge measurements were observed in 2009 after drilling through pingo ice to artesian sub-pingo water and compared with data collected from the same pingo in 1968. It is shown that the major mechanism for ice formation at this pingo is groundwater
artesian pressure, though not continuously. Four major stages of pingo growth after 8790 yr BP are inferred.
This paper describes the results of geological and palynological investigations of a pingo remnant in Friesland. The remnant is situated in a small, former tributary valley of the Boorne river. As contrasted with other pingo remnants
in The Netherlands, the Stokersdobbe is at its base filled with sand and gravel overlaid by a loam deposit of Bolling age. The decay of the pingo could be dated between 13.000 (Bolling) and 18.000 radiocarbon years B.P. The period of growth of the pingo is correlated
Résultats de forages dans des palses en dôme montrant que le sol entourant les pingos n'est pas gelé. Ces formes pourraient dater d'une période où le permafrost était plus répandu.
Arctique ; Coin de glace ; Glaciation ; Pingo ; Périglaciaire ; Svalbard ; Zone froide
Arctic Ocean;Arctic Region ; Cold areas ; Glaciation ; Ice wedges ; Periglacial features ; Pingos ; Svalbard
Primary research data from central Spitzbergen on periglacial processes, internal structure of pingos, ice-wedge polygons, and history of glaciation.- (DWG)