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Physical weathering, also called mechanical weathering or disaggregation, is the class of processes that causes the disintegration of rocks without chemical change. Physical weathering involves the breakdown of rocks into smaller fragments through processes such as expansion and contraction, mainly due to temperature changes.
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.
Exfoliation (or onion skin weathering) is the gradual removing of spall due to the cyclic increase and decrease in the temperature of the surface layers of the rock. Rocks do not conduct heat well, so when they are exposed to extreme heat, the outermost layer becomes much hotter than the rock underneath causing differential thermal expansion .
Exfoliating slabs of granite, on Half Dome in Yosemite National Park, USA. Exfoliating granite is a granite undergoing exfoliation, or onion skin weathering (desquamation).The external delaminated layers of granite are gradually produced by the cyclic variations of temperature at the surface of the rock in a process also called spalling.
Abrasion is a process of weathering that occurs when material being transported wears away at a surface over time, commonly occurring with ice and glaciers. The primary process of abrasion is physical weathering. Its the process of friction caused by scuffing, scratching, wearing down, marring, and rubbing away of materials.
Many explanations have been proposed for honeycomb and other cavernous weathering. These explanations include marine abrasion; wind corrosion; mechanical weathering resulting from short-term temperature variations; chemical weathering of the interior of the rock (core-softening) under a protective crust (case-hardening) followed by mechanical removal of the softened material; biogeochemical ...
The P-T conditions experienced by a rock throughout these processes can be classified into three main stages according to temperature changes: [3] Prograde (pre-peak) metamorphism: the process when the rock is buried and heated in environments such as basins or subduction zones. [3] Devolatilization reactions (release of gases e.g. CO 2, H 2 O ...
Wind erosion of soil at the foot of Chimborazo, Ecuador Rock carved by drifting sand below Fortification Rock in Arizona (Photo by Timothy H. O'Sullivan, USGS, 1871). Aeolian processes, also spelled eolian, [1] pertain to wind activity in the study of geology and weather and specifically to the wind's ability to shape the surface of the Earth (or other planets).