Weathering

Weathering

Weathering - decomposition and disintegration of rocks in situ. 

Decomposition refers to the chemical process and creates altered rock substances whereas disintergration or mechanical weathering produces smaller, angular fragments of the same rock. 

Weathering is important for landscape evolution as it breaks down rock and facilitates erosion and transport by rivers. 

Mechanical Weathering (physical) 

Freeze Thaw - Occurs when water in joints and cracks freezes at 0*, expands by 10% then exerts pressure. Rocks can only withstand a certain degree of pressure. It is most effective in environments where moisture is plentiful and there are frequent fluctuations above and below freezing point, such as periglacial and alpine regions. 

Salt Crystal Growth - Occurs in areas where temperatures fluctuate around 26-28*C and sodium carbonate expand by 300%. When water evaporates, salt crystals may be left behind to attack the structure. Both mechanics are frequent in hot desert regions. 

Disintegration - Found in hot desert…