Geology: Weathering

Weathering

Breaking down rocks into small pieces by chemical or physical means.

Physical weathering

The physical breakdown of bedrock

Chemical weathering

The breakdown of rocks via chemical methods

Sediments

Pieces of rock that have been weathered and possibly eroded

Soil

A type of non-eroded sediment mixed with organic matter, used by plants.

Erosion

The transport and movement of weathered sediments

Dissolution

The process in which solids (like minerals) are dissolved and the ionic components are dispersed in a liquid (usually water)

Hydrolysis

Water breaking into ions and replacing ions in minerals; a major type of chemical weathering in silicates.

Oxidation

Iron in minerals bonds with oxygen, causing reactions like rust

Exfoliation

A type of mechanical weathering in which outer layers of rock, approximately parallel to the surface, fracture off.

Frost wedging

A process where water freezes inside cracks in rocks, causing expansion and mechanical weathering.

Karst

Carbonate rocks which dissolve, leaving behind caverns and holes which affect the landscape.

Joint

A fracture in rocks along which little or no displacement has occurred

Talus

Loose blocks of rock that fall down from steep surfaces and cover slopes.