Cryosuction is the concept of negative pressure in freezing soil resulting from transformation of liquid water to ice in the
soil pore The pore space of soil contains the liquid and gas phases of soil, i.e., everything but the solid phase that contains mainly minerals of varying sizes as well as organic compounds.
In order to understand porosity better a series of equations have b ...
s whereby water migrates through soil pores to the freezing zone (through
capillary action
Capillary action (sometimes called capillarity, capillary motion, capillary rise, capillary effect, or wicking) is the process of a liquid flowing in a narrow space without the assistance of, or even in opposition to, any external forces li ...
).
Fine-grained soils such as clays and silts enables greater negative pressures than more coarse-grained soils due to the smaller pore size. In
periglacial
Periglaciation (adjective: "periglacial", also referring to places at the edges of glacial areas) describes geomorphic processes that result from seasonal thawing of snow in areas of permafrost, the runoff from which refreezes in ice wedges and ot ...
environments, this mechanism is highly significant and it is the predominant process in
ice lens
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, ...
formation in permafrost areas.
Several models for ice-lens formation by cryosuction exist, among others the Hydrodynamic model and the Pre-melting model, many of them based on the
Clausius–Clapeyron relation
The Clausius–Clapeyron relation, named after Rudolf Clausius and Benoît Paul Émile Clapeyron, specifies the temperature dependence of pressure, most importantly vapor pressure, at a discontinuous phase transition between two phases of matter ...
with various assumptions, yielding cryosuction potentials of 11 to 12 atm per degree Celsius below zero depending on pore size.
See also
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Pore water pressure
Pore water pressure (sometimes abbreviated to pwp) refers to the pressure of groundwater held within a soil or rock, in gaps between particles ( pores). Pore water pressures below the phreatic level of the groundwater are measured with piezometers. ...
*
Suction
Suction is the colloquial term to describe the air pressure differential between areas.
Removing air from a space results in a pressure differential. Suction pressure is therefore limited by external air pressure. Even a perfect vacuum cannot ...
*
Permafrost
Permafrost is ground that continuously remains below 0 °C (32 °F) for two or more years, located on land or under the ocean. Most common in the Northern Hemisphere, around 15% of the Northern Hemisphere or 11% of the global surface ...
References
Geography of the Arctic
Geomorphology
Hydrology
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