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CH3041
WEATHING RATES
Solubility
 Chemical weathering occurs primarily in the Vadose zone of soil (aerobic)
Ø Rate increases with: 1) Temperature
 2) H2O infiltration rate (GR)
 
 4) Dissolution rates at 25oC
of different minerals also
vary substantially with pH.
(GR= P± R- ET-MR)
3) Physical weathering
• There is an inverse
relationship between
particle size and solubility
as shown here for minerals
 goethite a-FeOOH &
 hematite a-Fe2O3