Weathering Project

Weathering
Weathering is the breaking down of Earth's rocks, soils and minerals through direct contact with the planet's atmosphere. Weathering occurs "with no movement", and thus is different than erosion, which involves the movement of rocks and minerals by agents such as water, ice, wind, and gravity.
In addition, weathering is the effect of atmospheric exposure to man-made structures and materials.
Classifications of weathering —
  1- Mechanical or physical weathering                                                                                                           Involves the breakdown of rocks and soils through direct contact with atmospheric conditions, such as heat, water, ice and pressure.
  2- Chemical or biological weathering,                                                                                             Involves the direct effect of atmospheric chemicals or biologically produced chemicals (also known as biological weathering   in the breakdown of rocks, soils and minerals.                  
Living organisms may contribute to mechanical weathering (as well as chemical weathering, see 'biological' weathering below). Lichens and mosses grow on essentially bare rock surfaces and create a more humid chemical microenvironment.
Chemical weathering changes the composition of rocks, often transforming them when water interacts with minerals to create various chemical reactions. Chemical weathering is a gradual and ongoing process
The materials left over after the rock breaks down combined with organic material creates soil. A soil derived from a single rock type can often be less in one or more minerals for good fertility, while a soil weathered from a mix of rock types (as in glacial, or   sediiments) often makes more fertile soil
The primary process in physical weathering is abrasion (the process by which clasts and other particles are reduced in size). Chemical and physical weathering often go hand in hand. Furthermore, the...