Tag: rivers, coasts and glaciation

Decomposition and disintegration and decomposition of rocks due to chemical reaction is called chemical weathering. Chemical weathering takes place through the process of solution, oxidation and carbonation. Solution refers to the dissolution of soluble particles and minerals from the rocks with the help of water in motion. The atmospheric oxygen in rain water when meet with mineral like iron, rusting takes place and the colour of the rock changes. The process is called oxidation. When the carbon dioxide present in water reacts with rocks new chemical substances like calcium carbonation and iron carbonate are formed. This process is called carbonation. 

Exfoliation is type of mechanical weathering, it is also known as onion weathering. The exfoliation refers to peeling off concentric shells of rocks due to combined actions of heat and wind in hot arid and semi-arid regions and monsoon lands. Exfoliation is more common over crystalline rocks.  

Carbonation is the reaction of carbonate or bicarbonate ions with minerals. The process of carbonation is also known as solution wherein atmospheric carbon dioxide after mixing with water forms carbonic acid which after reacting with carbonate rocks like limestoe forms calcium bicarbonate which is easily dissolved in water.

The exogenetic forces or processes are originated from the atmosphere. These forces are continuously engaged in the destruction of the relief features created by the endogenertic forces through their weathering, erosion, mass movement. 

Biological weathering refers to decomposition and disintegration of rocks due to organic material of both flora and fauna. Production of different kinds of organic acids such as humic acids, baterial acids, microfaunal acids etc produced by organic materials help in the decomposition and disintegration of rocks and soils.

Decomposition and disintegration of rocks due to chemical reaction is called chemical weathering. The chief agents of chemical weathering are air and water. By the action of this two agents, the minerals in rock undergo chemical change and form a new chemical substance. Chemical weathering is more dominant in the area of humid climate. 

The oxidation simply means a reaction of atmospheric oxygen to form oxides. The atmospheric oxygen after reacting with the rocks produces several types of oxides, iron oxide being the most important, which weaken the rocks to disintegrate.

Weathering describes the breaking down or dissolving of rocks and minerals on the surface of the Earth. Water, ice, acids, salts, plants, animals, and changes in weather conditions like temperature, moisture, precipitation, are all agents of weathering.

• The correct sequence of events of the soil erosion process is weathering, erosion, transportation.
  
• Weathering: It is a process by which small rocks are broken down into further smaller pieces.
  
• Erosion: The small fragments of rocks or dust formed by weathering process is moved by wind or water.
  
• Transportation: This is the process by which the sand or rock fragments are carried on to the other places.