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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.
Physical weathering involves the breakdown of rocks into smaller fragments through processes such as expansion and contraction, mainly due to temperature changes. Two types of physical breakdown are freeze-thaw weathering and thermal fracturing. Pressure release can also cause weathering without temperature change.
Spalling is a common mechanism of rock weathering, and occurs at the surface of a rock when there are large shear stresses under the surface. This form of mechanical weathering can be caused by freezing and thawing, unloading, thermal expansion and contraction, or salt deposition.
The main process that creates these accumulations is called nivation. It is a complex of processes that includes freeze–thaw action (weathering by the alternate freezing and melting of ice), mass movement (the downhill movement of substances under gravity), and erosion by meltwater which is the main agent of the surroundings' influence. [5]
The freezing and thawing action of the ice enlarges, widens, or causes further cracks in the bedrock as it changes volume across the ice/water phase transition (a form of hydraulic wedging), gradually loosening the rock between the joints. This produces large chunks of rock called joint blocks.
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 due to fluctuations in temperature above and below the freezing point.
1. Letting Meat Sit on the Countertop. Allowing raw meat to slowly defrost at room temperature can be a serious health hazard. As the food begins to warm up, harmful bacteria can rapidly multiply ...
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.