1. WEATHERING, EROSION & SOIL FORMATION

3. WEATHERING, EROSION, TRANSPORTATION
Weathering- Physical disintegration and chemical decomposition of rocks
Erosion- Physical removal
Transportation- Movement of eroded particles
Chemical vs. Physical Weathering
Effects of weathering
Surface alteration of outcrops
Spheroidal weathering
Differential weathering

4. Physical Weathering

7. Transport

8. Abrasion

10. WEATHERING, EROSION, TRANSPORTATION
Weathering- Physical disintegration and chemical decomposition of rocks
Erosion- Physical removal
Transportation- Movement of eroded particles
Chemical vs. Physical Weathering
Effects of weathering
Surface alteration of outcrops
Spheroidal weathering
Differential weathering

13. Differential Weathering

15. MECHANICAL WEATHERING
Disintegration of rocks
Frost Action
Frost wedging - rock pried apart along joints
water expands upon freezing (ice wedge)
Frost heaving

17. Frost Action

18. MECHANICAL WEATHERING
Pressure Release
sheet joint
exfoliation
exfoliation domes
Other
Plant growth; Burrowing animals
Pressure of salt crystals
Extreme temperature changes
Mechanical weathering increases surface area facilitating chemical weathering

21. Exfoliation

23. Organic Action

24. Mechanical Weathering
Growth of salt crystal in arid/semi-arid regions can split rocks
Heat and cold extremes can also cause rock breakage

25. CHEMICAL WEATHERING Decomposition of rock to form new substances
Equilibrium
Role of Oxygen
Fe in ferromagnesian minerals becomes oxidized
Hematite
Limonite

29. Chemical Weathering Carbonic Acid H2CO3 Role of Acid
Hydrogen ions in water
pH=-Log[H+] Acid/Base
Carbonic Acid H2CO3
CO2 + H2O -> H2CO3
H2CO3 -> H+ + HCO3- (in water)
Solution weathering- Karstic Features
Calcite (in limestone) dissolves in acidic water
fluted (channeled) rock surface
caves

32. Chemical Weathering Carbonic Acid H2CO3 Role of Acid
Hydrogen ions in water
pH=-Log[H+] Acid/Base
Carbonic Acid H2CO3
CO2 + H2O -> H2CO3
H2CO3 -> H+ + HCO3- (in water)
Solution weathering- Karstic Features
Calcite (in limestone) dissolves in acidic water
fluted (channeled) rock surface
caves

33. KARST

34. Chemical Weathering Chemical weathering of other minerals
Chemical weathering of feldspar
H+ + feldspar -> clay mineral
Chemical weathering of other minerals
Weathering and climate
Weathering Products

37. Chemical Weathering Chemical weathering of other minerals
Chemical weathering of feldspar
H+ + feldspar -> clay mineral
Chemical weathering of other minerals
Weathering and climate
Weathering Products