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The Goldich dissolution series concerns intrinsic mineral qualities, which were proven both by Goldich as well as preceding scientists to also be important for constraining weathering rates. Earlier work by Steidtmann [3] demonstrated that the order of ionic loss of a rock as it weathers is: CO 3 2-, Mg 2+, Na +, K +, SiO 2 −, Fe 2+/3+, and ...
[3] [4] Quartz is the most common mineral in the sand or silt fraction as it is resistant to chemical weathering, except under hot climate; [5] other common minerals are feldspars, micas and ferromagnesian minerals such as pyroxenes, amphiboles and olivines, which are dissolved or transformed in clay under the combined influence of physico ...
Chemical weathering mainly results from the excretion of organic acids and chelating compounds by bacteria [24] and fungi, [25] thought to increase under greenhouse effect. [26] Physical disintegration is the first stage in the transformation of parent material into soil.
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.
The regolith of a region is the product of its long weathering history; leaching and dispersion are dominant during the initial phase of weathering under humid conditions. [1] Saprolites form in high rainfall regions which result in chemical weathering and are characterised by distinct decomposition of the parent rock's mineralogy. [5]
Denudation can involve the removal of both solid particles and dissolved material. These include sub-processes of cryofracture, insolation weathering, slaking, salt weathering, bioturbation, and anthropogenic impacts. [4] Factors affecting denudation include: Anthropogenic (human) activity, including agriculture, damming, mining, and ...
The rate of weathering is sensitive to factors that change how much land is exposed. These factors include sea level , topography , lithology , and vegetation changes. [ 4 ] Furthermore, these geomorphic and chemical changes have worked in tandem with solar forcing, whether due to orbital changes or stellar evolution, to determine the global ...
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 ...