Weathering Flashcards
What are the two types of chemical weathering?
Carbonation
Hydrolysis
What are the three types of mechanical weathering?
Exfoliation
Frost shattering
Pressure release
What are the two types of biological weathering?
Burrowing
Root action
Outline carbonation
CO2 in the atmosphere reacts with rainwater & pore water in the soil to form carbonic acid
Makes groundwater acidic
Show carbonation of limestone
CaCO3 + H2CO3 → Ca2+ + 2HCO3-
Insoluble impurities are left behind as clay residues.
Outline hydrolysis
Reaction between silicate minerals and water
Sped up by carbonic acid
Products include clay, silica and a carbonate/bicarbonate (K, Na, Ca)
Outline exfoliation
Expansion and contraction of minerals eg in a desert due to heat.
Outline pressure release
Erosion of rock above, reduce the overlying pressure and the rock expands producing fractures
Outline root action
Roots grow along bedding planes forcing them apart, water penetrates and chemical weathering occurs
