define the following terms: weathering physical/mechanical weathering biological weathering describe: 2 types of physical weathering that happens on coasts 1 type of checmial weathierng that occurs on coasts 2 type of biological weatheirng that occurs on coasts what does mass movement mean

Weathering is the breakdown of rocks at the Earth’s surface by weathering agents such as water , wind , temperature , etc.

There are 3 types of weathering :-

◇ Physical / Mechanical Weathering =

•Physical weathering is caused by the effects of changing temperature on rocks, causing the rock to break apart

•Physical weathering happens especially in places places where there is little soil and few plants grow, such as in mountain regions and hot deserts.

•There are 2 types of physical weathering which occurs on coastal areas are :-

▪ Freezing Thaw

▪ Exfoliation

◇ Chemical Weathering =

•Chemical weathering is caused by rain water reacting with the mineral grains in rocks to form new minerals (clays) and soluble salts. These reactions occur particularly when the water is slightly acidic.

•These chemical processes need water, and occur more rapidly at higher temperature, so warm, damp climates are best. Chemical weathering is the first stage in the production of soils.

•Usually Oxidation occurs on the shoreline rocks where iron elements are present within rocks. The ‘rusting’ of the iron content may cause rocks to disintegrate.

◇ Biological Weathering =

•Biological weathering is weathering caused by plants and animals. Plants and animals release acid forming chemicals that cause weathering and also contribute to the breaking down of rocks and landforms.

•Trees put down roots through joints or cracks in the rock in order to find moisture. As the tree grows, the roots gradually prize the rock apart. Even lichens when grow on rocks , they secrete some chemicals which also breaks down the rock.