Weathering

Two types of weathering

1. Physical (Mechanical)

2. Chemical

Physical Weathering

rocks broken down into smaller pieces by external conditions (not changing the material)

Chemical Weathering

rocks broken down through chemical changes (changing the material)

Abrasion

scrapping of rock surfaces by hitting other rocks/sand (mechanical weathering)

Ice wedging (frost action)

water gets into cracks and freezes causing the cracks to get bigger (mechanical weathering)

animal action

animals burrow and dig moving sediments (mechanical weathering)

root wedging

rocks are broken due to plants as they grow through cracks (mechanical weathering)

exfoliation (pressure release)

sheets of rocks breaking off due to release of pressure (mechanical weathering)

Hydrolysis

water weathers rock by dissolving it (chemical weathering), dissolve minerals and chemically alters them

oxidation

oxygen combines with minerals that have iron causing "rusting" (chemical weathering)

acid rain

gases react chemically with water forming acids such as like sulfuric acid and nitric acid from burning fossil fuels (chemical weathering)

Warm and Wet Climate

This climate would have more chemical weathering

Cool and Wet Climate

this climate would have more physical weathering (ice wedging)

Agent Wind

this agent can create sorted sediments. Sediments undergo abrasion.

Agent Water

this agent can create sorted, rounded rocks. Sediments undergo abrasion.

Agent Gravity

this agent creates piles of unsorted, jagged rocks on the bottom of mountains and cliffs

Erosion

The process by which wind and water transports soil and sediment from one location to another

Weathering rate

The weathering rate is the rate in which a rock breaks down. Dependent on climate and rock type

Surface area and weathering

-Physical weathering increases surface area

-Chemical weathering rates are directly proportional to surface area

-Therefor physical weathering increasing chemical weathering rates

Lichens are

symbiotic association of algae and fungi

Lichens produce

a weak acid that breaks down all sorts of things including rocks

Carbonic acid/carbonation

a very weak acid formed in solution when carbon dioxide dissolves in water.