Rivers And Oceans

Front 1

Types of "weathering"

Back 1

1) Physical
2) Chemical

Front 2

Define physical weathering and give examples of different processes

Back 2

no change in
chemical composition--just disintegration into
smaller pieces

physical breakup of rock due to:
• pressure release
• freeze & thaw of water
• crystallization of salt(s) within rocks
• thermal expansion and contraction

Front 3

Define chemical weathering and give examples of different processes

Back 3

breakdown as a result
of chemical reactions

Most of this is due to the fact many ionic and organic compounds dissolve in water. When exposed to the H+ ion, many of these minerals are easily broken down.

Front 4

Oxidation

Back 4

Oxygen dissolved in water
promotes oxidation of sulfides, ferrous
oxides, native metals (rusting)

Front 5

Hydration

Back 5

attachment of water molecules to
crystalline structure of a rock, causing
expansion and weakness

Front 6

Hydrolysis

Back 6

combination of hydrogen and
oxygen in water with rock to form new
substances

Front 7

Climatic catalysitc effects of progression of weathering

Back 7

Chemical weathering:
Most effective in areas of warm, moist climates – decaying vegetation creates acids that enhance weathering

Mechanical weathering:
Enhanced where there are frequent freeze-thaw cycles

Front 8

Soil

Back 8

Solid earth material that has been altered by physical, chemical
and organic processes so that it can support rooted plant life.