Search results
Results from the WOW.Com Content Network
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.
Frost weathering is the collective name for those forms of physical weathering that are caused by the formation of ice within rock outcrops. It was long believed that the most important of these is frost wedging, which is the widening of cracks or joints in rocks resulting from the expansion of porewater when it freezes. A growing body of ...
German masons repointing a wall in 1948. Repointing is the process of renewing the pointing, which is the external part of mortar joints, in masonry construction. Over time, weathering and decay cause voids in the joints between masonry units, usually in bricks, allowing the undesirable entrance of water.
Ice lens formation resulting in frost heave in cold climates. Frost heave is the process by which the freezing of water-saturated soil causes the deformation and upward thrust of the ground surface. [3] This process can distort and crack pavement, damage the foundations of buildings and displace soil in regular patterns.
Typically, hoodoos form from weathering processes that continuously work together in eroding the edges of a rock formation known as a fin. For example, the primary weathering force at Bryce Canyon is frost wedging. The hoodoos at Bryce Canyon experience more than 200 freeze-thaw cycles each year.
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.
[9] [10] In 1935, Melik discovered that frost weathering had been a very successful geomorphic process in non-glaciated regions of the Slovenian Alps throughout the Pleistocene. The word "periglacial" was not well-known at the time so he merely emphasized enhanced transit of scree down the slopes in relation to mass movement processes.
Frost damage can occur as cracks, stone splinters and swelling of the material. When water freezes, the volume of water increases by 9 %. [ citation needed ] When the volumetric moisture content exceeds 91 %, then the volume increase of water in the pores of the material caused by freezing cannot be absorbed by sufficient empty pores.