Pingo formed in arctic tundra as a result of periodically spaced ice lens formation.
Ice lenses are bodies of ice formed when moisture, diffused within soil or rock, accumulates in a localized zone. The ice initially accumulates within small collocated pores or pre-existing crack, and, as long as the conditions remain favorable, continues to collect in the ice layer or ice lens, wedging the soil or rock apart. Ice lenses grow parallel to the surface and several centimeters to several decimeters (inches to feet) deep in the soil or rock. Studies from 1990 have demonstrated that rock fracture by ice segregation (i.e., the fracture of intact rock by ice lenses that grow by drawing water from their surroundings during periods of sustained subfreezing temperatures) is a more effective weathering process than the freeze-thaw process which older texts proposed.[1]
Ice lenses play a key role in frost induced heaving of soils and fracture of bedrock, which are fundamental to weathering in cold regions. Frost heaving creates debris and dramatically shapes landscapes into complex patterns. Although rock fracture in periglacial regions (alpine, subpolar and polar) has often been attributed to the freezing and volumetric expansion of water trapped within pores and cracks, the majority of frost heaving and of bedrock fracture results instead from ice segregation and lens growth in the near-surface frozen regions. Ice segregation results in rock fracture and frost heave.[2]
^"Periglacial weathering and headwall erosion in cirque glacier bergschrunds"; Johnny W. Sanders, Kurt M. Cuffey, Jeffrey R. Moore, Kelly R. MacGregor and Jeffrey L. Kavanaugh; Geology; July 18, 2012, doi:10.1130/G33330.1
^Cite error: The named reference Murton2006 was invoked but never defined (see the help page).
Icelenses are bodies of ice formed when moisture, diffused within soil or rock, accumulates in a localized zone. The ice initially accumulates within...
growth of the ice and can promote the formation of lens-shaped areas of ice within the soil. Yet the force of one or more growing icelenses is sufficient...
Ice segregation is the geological phenomenon produced by the formation of icelenses, which induce erosion when moisture, diffused within soil or rock...
subglacial icelens formation, which contributes to the overdeepening process. Bands of sediment or glacial till have been observed below Antarctic ice sheets;...
during the following summer thaw, leaving a small surface depression. Some icelenses grow and form larger surface hummocks ("pingos") which can last for many...
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contributes to the formation of an icelens which grows by drawing up surrounding water. The expansion of the ice upon freezing exerts pressure on the...
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granular structure with many very distinctive crystalline shapes (such as icelenses). Separation of coarse from fine soil materials produces distinctive patterned...
and it is the predominant process in icelens formation in permafrost areas. As of 2001, several models for ice-lens formation by cryosuction existed, among...
to the ingenuity of Doctor Clawbonny (who is able to make fire with an icelens, make bullets from frozen mercury and repel attacks by polar bears with...
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of physical structure designed to emit light from a system of lamps and lenses and to serve as a beacon for navigational aid, for maritime pilots at sea...
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specially-made lens that is crucial to its functioning. Realizing that next alignment would not be until 2162, "Bill" calls in a favor to procure the lens early...
with f/1.8 lens, IR laser-assisted autofocus, optical and electronic image stabilization; 8 MP front camera with f/1.8 lens and 75° lens, second front...
different types of camera motion Panorama stitching from video Automatic lens vignette removal Automatic cropping to maximum image area Optional automatic...
expansion of freezing water in cell lumens, and additionally the formation of icelenses within wood. As stated, previous defects such as healed wounds, branch...
ice core analyses conducted on frost boils has found that samples extracted from the center of Frost Boils have higher concentration of icelenses in...
filled with soil material. I layers: These are icelenses and wedges that contain at least 75 per cent ice (by volume) and that distinctly separate layers...
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