Periglacial features an phenomena related to PermafrostMost photos on this page are from Ny Friesland, where the climate is particularly cold and dry; on the nunataks, vegetation is sparse, but an active layer develops in the short summer, allowing periglacial processes to take place. There the photographs were taken on two nunataks (Dracoisen and Ditlovtoppen) at about 550 to 700 metres above sea level in summer 2010. Photos lower down on the page are from Ny-Ålesund and Longyerbyen, where the climate is somewhat more maritime, and were taken in July 2009. |
Frost-shattered dolomite boulder at Ditlovtoppen, Ny Friesland. The broken fragments are being transported downslope by solifluction. Trekking pole for scale (MH). | Bedrock near the surface fractures and undergoes sorting by freeze-thaw processes. Here at Ditlovtoppen, Ny Friesland, Carboniferous shales are forming distinct patterns at the surface (MH). | Bedrock lithology has a profound effect on the style of frost-sorting. Here at Ditlovtoppen, Ny Friesland, blocks of Carboniferous sandstone are concentrated in roughly formed buried ice wedges (MH). | Complete breakdown of the bedrock gives rise to blockfields, commonly known as felsenmeer. The material in this view from Ditlovtoppen, Ny Friesland, is Carboniferous sandstone (MH). |
Stone stripes are a feature of frost-sorting on slopes, as here on “Multikolorfjellet” adjacent to Polarisbreen. Ny Friesland (MH). | Close-up of stone stripes on Dracoisen, Ny Friesland, illustrating sorting of pale dolostone material and grey shale fragments (MH). | A large stone circle involving sorting of dolomitic material at Dracoisen, Ny Friesland (MH). | Small-scale polygons result from segregation of fine sediment and gravel-sized material. These examples at Ditlovtoppen are 10-20 cm across and formed in highly weathered Carboniferous sandstone and mudstone (MH). |
Roughly formed polygons at Ditlovtoppen, Ny Friesland, comprising large blocks of Carboniferous sandstone (MH). | Downslope movement of perennially saturated ground is accomplished by creep, giving rise to these solifluction lobes at Dracoisen, Ny Friesland (MH). | Large-scale (2 m-high) solifluction lobes on a low-angle slope, comprising blocks of Carboniferous sandstone. Summit of Ditlovtoppen in background (MH). | Slow mass-movement of hut-sized Carboniferous limestone over water-saturated shale of late Precambrian age is evident in this telephoto of the northern end of Dracoisen (MH). |
The same mass movement location from the lower edge of the zone of transported blocks (MH). | Minature pingos (frost boils) at Ditlovtoppen, Ny Friesland are only observed in a bed of coaly shale (MH). | Stone circles in Brøggerdalen, southwest of Ny-Ålesund (JA). | Detail of the same stone circles as in the previous photo, fisheye lens (JA). |
Small rock glaciers at the base of a cliff (Steinflåstupet) W of Ny-Ålesund (JA). | Small rock glacier in Brøggeralen, SW of Ny-Ålesund (panorama, requires scrolling to the right; JA). | Ice wedge polygons along the SW coast of Brøggerhalvøya (JA). | Rapid spring runoff causes considerable fluvial erosion and delta formation (SW coast of Brøggerhalvøya, JA). |
Alluvial fan, ice wedge polygons and raised beaches (SW coast of Brøggerhalvøya, JA). | Solifluction is evident in Longyerbyen where posts formerly used as foundations of tramway pylons have tilted downslope (JA). | Buildings constructed in areas affected by permafrost need to be insulated from the ground (UNIS, The University Centre in Svalbard; JA). | |
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