weathering
DESCRIPTION
Weathering. Rocks and Weathering. Weathering: is the process that breaks down rock and other substances at Earth’s surface Heat, cold, water, ice, oxygen, CO 2 Erosion: is the removal of rock particles by wind, water, ice, or gravity - PowerPoint PPT PresentationTRANSCRIPT
WEATHERING
Rocks and Weathering
Weathering: is the process that breaks down rock and other substances at Earth’s surface Heat, cold, water, ice, oxygen, CO2
Erosion: is the removal of rock particles by wind, water, ice, or gravity
Uniformitarianism: same processes that happens today happened in the past.
Two Kinds of Weathering
Mechanical: physically breaking down rocks Examples: splitting or cracking of rocks, hit a
rock with a hammer Causes: freezing and thawing, release of
pressure, plant growth, action of animals, and abrasion Abrasion: grinding away of rock by rock particles
carried by water, ice, wind or gravity. Ice wedging: freezing and thawing in rocks. Caused
by water’s property of expanding when frozen. See diagram on Page 40 to 41 G
Mechanical Weathering
Ice wedginghays.outcrop.org
Abrasion lyricsdog.eu
Two Kinds of Weathering Continue Chemical Weathering: process that breaks
down rock through chemical changes Cause: water, oxygen, CO2, living organisms, and
acid rain Water: dissolves rock Oxygen: oxidation: the process of iron and oxygen
reacting with each other with water to form rust. CO2 : Carbonic acid: CO2 dissolved in water = weak
acid. Weathers limestone and marble Living Organism: when plants grown in cracks of
rocks, their roots produce a weak acid that dissolves the rock. Lichens, which are a plant like organisms, also produces a weak acid that dissolves rocks.
Acid Rain: air pollution mixes with water vapor to form acid rain, which causes rapid chemical weathering.
Chemical Weathering
Living organismscgz.e2bn.net
Waterfotopedia.com
Rate of Weathering
Rock type: Minerals: determine how fast they dissolve in
water Permeable: rocks are full of tiny, connected air
spaces (like a sponge) that water seep through them.
Climate: Average weather conditions in an area
Precipitation and temperature Rain, freezing and thawing, temperature
(higher = faster rate) Hot and wet climates = faster rate
The Process of Soil Formation Soil forms as rock is broken down by
weathering and mixes with other materials on the surface.
Soli horizon: layer of soil that differ in color and texture from the layer above and below it
Rate at which it forms depends on climate and rock type
Soil
Soil Horizonincreasemyvocabulary.com
Process of soil formationagcal.usask.ca