weathering

Weathering describes the breaking down or dissolve of rocks and minerals on the surface of the Earth. Water, ice, acids, salts, plants, animals, and also changes in temperature space all agents the weathering.

You are watching: The type of weathering in which rock is physically broken into smaller pieces


Weathering defines the breaking under or dissolving of rocks and also minerals ~ above the surface of the Earth. Water, ice, acids, salts, plants, animals, and changes in temperature are all agents the weathering.
Once a rock has been damaged down, a procedure called erosion transports the bits that rock and mineral away. No rock on planet is hard enough to withstand the pressures of weathering and erosion. Together, this processes sculpted landmarks such together the grand Canyon, in the U.S. State of Arizona. This substantial canyon is 446 kilometers (277 miles) long, as much as 29 kilometers (18 miles) wide, and also 1,600 meters (1 mile) deep.
Weathering and erosion constantly adjust the rocky landscape of Earth. Weathering wears far exposed surfaces end time. The size of exposure frequently contributes to how breakable a rock is to weathering. Rocks, such together lavas, that room quickly hidden beneath other rocks room less vulnerable to weathering and erosion than rocks that space exposed come agents such as wind and also water.
As it smoothes rough, spicy rock surfaces, weathering is often the very first step in the production of soils. Small bits of weathered minerals mix v plants, animal remains, fungi, bacteria, and also other organisms. A single kind of weathering rock frequently produces infertile soil, while weathered materials from a arsenal of rocks is richer in mineral diversity and also contributes to an ext fertile soil. Soils species associated v a mixture of weathered rock include glacial till, loess, and alluvial sediments.
Weathering is often separated into the procedures of mechanical weathering and also chemical weathering. Organic weathering, in which living or once-living organisms contribute to weathering, deserve to be a component of both processes.
Water, in either fluid or solid form, is frequently a key agent of mechanically weathering. Because that instance, liquid water can seep right into cracks and crevices in rock. If temperature drop short enough, the water will freeze. When water freezes, the expands. The ice then works as a wedge. It progressively widens the cracks and splits the rock. As soon as ice melts, liquid water performs the plot of erosion by transporting away the tiny rock pieces lost in the split. This specific procedure (the freeze-thaw cycle) is dubbed frost weathering or cryofracturing.
Temperature changes can also contribute to mechanical weathering in a procedure called thermal stress. Alters in temperature cause rock to expand (with heat) and contract (with cold). Together this wake up over and also over again, the framework of the absent weakens. End time, that crumbles. Rocky desert landscapes are particularly vulnerable to heat stress. The external layer of desert rocks undergo repeated stress together the temperature changes from day come night. Eventually, outer layers flake turn off in thin sheets, a process called exfoliation.
Exfoliation contributes come the development ofbornhardts, one of the most dramatic functions in landscapes created by weathering and erosion. Bornhardts room tall, domed, secluded rocks often found in tropical areas. Sugarloaf Mountain, an iconic landmark in Rio de Janeiro, Brazil, is a bornhardt.
Changes in push can additionally contribute to exfoliation because of weathering. In a process called unloading, overlying products are removed. The underlying rocks, released from overlying pressure, have the right to then expand. Together the rock surface ar expands, that becomes vulnerable to fracturing in a procedure called sheeting.
Another type of mechanical weathering occurs as soon as clay or other materials near absent absorb water. Clay, an ext porous 보다 rock, deserve to swell with water, weathering the surrounding, more difficult rock.
Salt additionally works to weather rock in a procedure called haloclasty. Saltwater periodically gets right into the cracks and also pores that rock. If the saltwater evaporates, salt crystals space left behind. Together the crystals grow, castle put press on the rock, slowly breaking that apart.
Honeycomb weathering is linked with haloclasty. Together its surname implies, honeycomb weathering explains rock formations through hundreds or even thousands the pits formed by the development of salt crystals. Honeycomb weathering is common in seaside areas, where sea sprays constantly force rocks to connect with salts.
Haloclasty is not restricted to seaside landscapes. Salt upwelling, the geologic process in which secret salt domes expand, can add to weathering that the overlying rock. Structures in the old city that Petra, Jordan, were made unstable and also often fell down due come salt upwelling indigenous the ground below.
Plants and animals can be agents of mechanically weathering. The particle of a tree might sprout in soil that has collected in a cracked rock. As the roots grow, they widen the cracks, eventually breaking the rock into pieces. End time, trees can break personally even huge rocks. Even tiny plants, such together mosses, can enlarge tiny cracks together they grow.
Animals that tunnel underground, such together moles and prairie dogs, additionally work to rest apart rock and soil. Other pets dig and trample absent aboveground, bring about rock to slowly crumble.
For instance, carbon dioxide from the air or soil periodically combines with water in a procedure called carbonation. This to produce a weak acid, dubbed carbonic acid, that have the right to dissolve rock. Carbonic acid is especially effective at dissolve limestone. When carbonic acid seeps v limestone underground, it have the right to open up huge cracks or hole out substantial networks the caves.
Carlsbad Caverns national Park, in the U.S. State of new Mexico, includes an ext than 119 limestone caves produced by weathering and also erosion. The largest is dubbed the large Room. V an area of about 33,210 square meter (357,469 square feet), the large Room is the size of six football fields.
Sometimes, chemistry weathering dissolves big portions that limestone or various other rock on the surface ar of the earth to type a landscape called karst. In this areas, the surface rock is pockmarked through holes, sinkholes, and caves. One of the world’s many spectacular instances of karst is Shilin, or the stone Forest, close to Kunming, China. Thousands of slender, sharp towers of weathered limestone rise from the landscape.
Another kind of chemistry weathering works on rocks that contain iron. These rocks rotate to rust in a process called oxidation. Rust is a compound produced by the interaction of oxygen and iron in the visibility of water. As rust expands, it weakens rock and helps break it apart.
Hydration is a kind of chemistry weathering in i m sorry the chemistry bonds that the mineral are readjusted as the interacts with water. One circumstances of hydration occurs together the mineral anhydrite reacts v groundwater. The water transforms anhydrite into gypsum, among the most usual minerals ~ above Earth.
Another familiar form of chemical weathering is hydrolysis. In the procedure of hydrolysis, a brand-new solution (a mixture of 2 or an ext substances) is created as chemistry in rock communicate with water. In countless rocks, for example, sodium minerals interact with water to type a saltwater solution.
Hydration and also hydrolysis add to flared slopes, another dramatic example of a landscape created by weathering and erosion. Flared slopes are concave rock formations occasionally nicknamed “wave rocks.” their c-shape is greatly a result of subsurface weathering, in i beg your pardon hydration and hydrolysis wear away rocks beneath the landscape’s surface.
Living or once-living organisms can likewise be agents of chemistry weathering. The decaying remains of plants and some fungi form carbonic acid, which have the right to weaken and dissolve rock. Some bacteria have the right to weather absent in stimulate to access nutrients such as magnesium or potassium.
Clay minerals, consisting of quartz, are among the most typical byproducts of chemistry weathering. Clays do up around 40% of the chemistry in all sedimentary rocks top top Earth.
For example, details kinds of waiting pollution increase the price of weathering. Burn coal, natural gas, and petroleum releases chemicals such as nitrogen oxide and sulfur dioxide right into the atmosphere. Once these chemicals integrate with sunlight and moisture, they adjust into acids. They then fall earlier to planet as mountain rain.
Acid rain quickly weathers limestone, marble, and other kinds of stone. The results of acid rain can frequently be viewed on gravestones, make names and other inscriptions impossible to read.
Acid rain has additionally damaged plenty of historic buildings and also monuments. For example, at 71 meters (233 feet) tall, the Leshan large Buddha at mountain Emei, China is the world’s biggest statue of the Buddha. It was sculpted 1,300 years back and sat unharmed for centuries. An innovative drainage mechanism mitigates the natural process of erosion. However in current years, acid rain has turned the statue’s sleep black and also made several of its hair crumble and fall.

Weathering by water"s freeze-thaw cycle has break-up this rock in two.

Photograph by George F. Mobley, national Geographic


Spheroidal weathering is a kind of chemistry weathering the occurs when a rectangle-shaped block is weathering from 3 sides at the corners and also from two sides along its edges. It is also called “onion skin” weathering.

Weathered MountainsThe Appalachian mountains in eastern North America as soon as towered more than 9,000 meter (30,000 feet) high—taller 보다 Mount Everest! Over countless years, weathering and erosion have actually worn them down. Today, the greatest Appalachian height reaches simply 2,037 meter (6,684 feet) high.


chemical compound that reacts with a base to kind a salt. Acids have the right to corrode some herbal materials. Acids have actually pH levels reduced than 7.


precipitation through high levels of nitric and also sulfuric acids. Acid rain have the right to be manmade or happen naturally.


process in which living or once-living organisms add to the disintegration of rocks and also minerals (weathering).


(c. 563-483 BCE) Indian prince, spiritual leader, and also founder that the buddhist religion. Also called Prince Siddhartha and also Gautama Buddha.


process changes the composition of rocks, frequently transforming them as soon as water interacts v minerals to create various chemical reactions.


chemical weathering procedure in i m sorry the freeze-thaw bike of ice cracks and also disintegrates rock. Also called frost weathering.


type that mineral that is clear and, as soon as viewed under a microscope, has a repeating pattern of atoms and molecules.


process of rocks crumbling as result of rain, wind, or other atmospheric conditions. Additionally called mechanically weathering and physical weathering.


C-shaped landform consists of a concave rock wall surface formed by weathering and also erosion that subsurface rocks. Additionally called a “wave rock.”


chemical weathering process in i m sorry the freeze-thaw cycle of ice cracks and disintegrates rock. Likewise called cryofracturing.


stone noting a person"s interment place, often engraved v the person"s name and also dates of birth and death.


type that sedimentary rock greatly made the calcium lead carbonate from shells and skeletons of naval organisms.


process that rocks crumbling due to rain, wind, or various other atmospheric conditions. Additionally called physical weathering.


chemical process of a problem combining with oxygen to readjust the substance"s physical and molecular structure.


process of rocks crumbling due to rain, wind, or other atmospheric conditions. Also called mechanically weathering.


part the a plant that secures the in the soil, obtains water and also nutrients, and often shop food make by leaves.


structure developed as water evaporates indigenous a salty lake or sea. The remaining salt is buried by sediments, yet eventually pierces v the rock, developing a hill.


type of physics weathering in which a single layer of rock is damaged off. Also called contour weathering.

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existing in the tropics, the latitudes in between the Tropic the Cancer in the north and the Tropic the Capricorn in the south.


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