Which Of The Following Factors Control How Minerals Weather?

viii.3 Controls on Weathering Processes and Rates

Weathering does not happen at the same rate in all environments. The same types of weathering do non happen in all environments. There are a variety of factors that determine what kinds of weathering volition occur, and how fast the processes will proceed.

Climate

Water and temperature are key factors decision-making both weathering rates and the types of weathering that occur:

H2o is required for chemical weathering reactions to occur.
Water must be nowadays for ice wedging to happen.
Higher temperatures speed up chemical reactions.
Climate will determine whether water is present mostly in liquid grade, solid form (ice), or both.
Climate will make up one's mind what plant life is available to force rocks apart with their roots, and to contribute organic acids to soils to aid in chemical weathering.

This means, for case, that chemical weathering volition be faster in a tropical rainforest than in the Chill, a cold desert. Information technology means physical weathering will exist the predominant form of weathering in the Arctic.

Oxygen and Carbon Dioxide

The presence and abundance of oxygen and carbon dioxide affect chemic weathering rates. Surface environments on Globe almost all take some complimentary oxygen available, permitting oxidation reactions to take place. Exceptions are in settings such as deep lakes or swamps where oxygen cannot easily mix into the water, and where biological processes consume the oxygen chop-chop.

Carbon dioxide, which acidifies water and contributes to chemic weathering, is more than concentrated in some settings than others. For instance, considering of the activities of organisms, soils can take very loftier concentrations of carbon dioxide, whereas carbon dioxide concentrations will be lower on surfaces gratis of soils and exposed to the atmosphere.

Minerals

The minerals making up a stone will decide what kinds of chemical weathering reactions are possible, and how chop-chop chemical weathering reactions occur. Under the same conditions, dissolution of the calcite making upwards limestone will occur more than rapidly than hydrolysis reactions happening to feldspar in granite. Quartz is very resilient to chemical weathering, and will remain long after calcite and feldspar have been weathered away. A rock with grains cemented by calcite will weather faster than a stone with grains cemented by quartz.

In full general, differences in the rates of chemic weathering amid minerals can be broken downwards as follows:

Minerals that weather by dissolution (e.g., halite, gypsum, calcite) are the easiest to weather.
Silicate minerals with lower silica to oxygen ratios (e.chiliad., silicates made of isolated silica tetrahedra or unmarried chains) are easier to weather than silicate minerals with higher ratios (east.grand., those made of silica tetrahedra arranged sheets or frameworks).
Minerals that are by-products of chemical weathering are some of the most resistant to further chemical weathering, although they may exist more than decumbent to physical weathering (e.yard., dirt minerals).

Weathering Makes Weathering Get Faster

Weathering accelerates weathering. Physical weathering forms cracks and breaks rocks autonomously into smaller pieces. The smaller the pieces, the greater the surface surface area exposed to chemical weathering. When the newly exposed surfaces are exposed to chemical weathering, it weakens the rock fifty-fifty further, making it more than susceptible to concrete weathering processes.

Differential Weathering

When rocks in an outcrop weather at different rates, the result is called differential weathering. Differential weathering causes some beds in an outcrop to be recessed relative to the others, because beds that are slow to conditions will take longer to recede than weaker beds (Figure eight.15).