Weathering, or the process of rock and mineral breakdown through natural forces such as water, ice, acids, salts, plants and animals as well as temperature variations is known as weathering.
Chemical weathering encompasses processes like carbonation (the dissolving of cations like magnesium and calcium), hydrolysis (minerals reacted with water forming solutions like feldspar becoming clay), and oxidation (iron turning to rust). Different rocks weather differently over time.
Physical
Weathering refers to the process of breaking down and dissolving rocks and minerals on Earth’s surface through factors like water, ice, acids, salts, plants, animals as well as changes in temperature as agents of weathering.
Mechanical or physical weathering breaks rocks down into smaller fragments without altering their composition, usually through stress along natural areas of weakness such as bedding planes, fractures or joints. Weathering also occurs due to freeze-thaw processes or heating.
Chemical weathering can be improved by increasing surface area. Think of granulated sugar dissolving more slowly into water than when in its lump form.
Biological weathering refers to the action of both plants and animals on rocks. Rabbits might burrow into cracks in rocks and as they move, they widen them further; similarly, plants may grow into these spaces by wedging.
Chemical
Chemical weathering occurs when environmental elements, like water and air, interact with minerals found within rocks to alter their chemical makeup and cause it to break apart into smaller pieces, which then can be carried away by either water or air currents. This form of weathering tends to occur more frequently in warm, wet climates.
Chemical weathering reactions typically include solution, hydration, oxidation and hydrolysis processes. When granite comes into contact with water it turns to clay minerals; these chemical changes also weaken the rock, increasing its chance of breaking apart more readily. Water may dissolve calcite from limestone rocks in caves to form stalagmites and stalactites – an example of chemical weathering at work!
Acidic chemical weathering removes essential minerals such as calcium from rocks through weathering processes such as acid rain. This process erodes marble and limestone sculptures, buildings, and roads over time, as well as contributing to acid rain – formed when industrial pollutants react with oxygen in the air to form acids such as sulfuric and carbonic.
Abrasion
Chemical weathering occurs when atmospheric chemicals come in contact with rocks or soil and alter their composition, such as when rain or snow drenches onto rocks to dissolve parts, or when small particles such as sand carried by wind or water come in contact with rocks to cause them to break down into smaller and smaller pieces or even crumble altogether. Chemical weathering tends to occur more in warmer, wetter environments.
Abrasion occurs when two rocks collide against each other, such as when rocks slide down a mountainside or fall over the edge of a cliff, or water flows in streams carrying sand against other rocks. Abrasion may also happen when glaciers scrape against their surroundings as well.
Shape can have an impactful effect on wear rates; rounder smooth particles tend to wear down more rapidly than sharp angular ones.
Erosion
At every scale across the planet, erosion gradually alters rock into ever-evolving landscapes. Water is a key force in this process as it washes away sediments. Wind and ice also play a part in dispersing particles around. Glaciers also contribute by picking up rocks along their paths before depositing them later.
Physical weathering makes rocks smaller or smoother and can form cliffs or canyons; an example being how the Colorado River carved the Grand Canyon over millions of years. On the other hand, biological weathering involves plant roots finding cracks between rocks that gradually widen over time – for instance by entering them via cracks between cracks in rocks to expand them gradually.
Chemical weathering erodes rocks by changing its surface minerals, weakening it and making it easier for it to break apart or wear down. Acid rain may dissolve some minerals that make up a rock, creating what is sometimes known as acid weathering.