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Frost weathering is a collective term for several mechanical weathering processes induced by stresses created by the freezing of water into ice. The term serves as an umbrella term for a variety of processes, such as frost shattering, frost wedging, and cryofracturing.
The term "felsenmeer" comes from the German meaning "sea of rock". In a felsenmeer or blockfield, freeze-thaw weathering has broken up the top layer of the rock, covering the underlying rock formation with jagged, angular boulders. Freeze-thaw or frost weathering occurs when water that is trapped along microcracks in rock expands and contracts ...
In addition to chemical and physical weathering of hydraulic action, freeze-thaw cycles, and more, there is a suite of processes which have long been considered to contribute significantly to bedrock channel erosion include plucking, abrasion (due to both bedload and suspended load), solution, and cavitation.
Two types of physical breakdown are freeze-thaw weathering and thermal fracturing. Pressure release can also cause weathering without temperature change. It is usually much less important than chemical weathering, but can be significant in subarctic or alpine environments. [5] Furthermore, chemical and physical weathering often go hand in hand.
Higher altitudes are associated with more periglacial activity due to colder temperatures, increased freeze-thaw cycles, and greater exposure to wind and snow accumulation. These conditions favor processes like frost heaving, solifluction, and ice wedge formation, which are hallmarks of periglacial environments.
The effect of expansion during freezing can be dramatic, and ice expansion is a basic cause of freeze-thaw weathering of rock in nature and damage to building foundations and roadways from frost heaving. It is also a common cause of the flooding of houses when water pipes burst due to the pressure of expanding water when it freezes. [9]
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]
Physical causes. Topography: Slope aspect and gradient; Geological factors: Discontinuity factors (dip spacing, asperity, dip and length) Physical characteristics of the rock (rock strength etc.) Tectonic activity: Seismic activity (earthquakes) Volcanic eruption; Physical weathering: Thawing; Freeze-thaw; Soil erosion; Hydrogeological factors ...