WEATHERING
What is weathering?
The BREAKING DOWN/disintegration/dissloving of rocks into smaller peices/solube material, at the surface by elements/effects of the weather
What is Erosion?
Erosion is the carrying away/transport or removing rocks and sediment to a new location
What is Physical/Mechanical Weathering?
break down of rocks into smaller pieces/fragments WITHOUT NO change in mineral/chemical composition
What is Chemical Weathering?
The process that breaks down rocks through a chemical change.
When does erosion happen in the cycle?
A. before weathering B. after weathering
C. after deposition
b. after weathering
What is the correct order of the 3 parts of the denudation cycle?
weathering, erosion, deposition
What are the agents of erosion
Wind, water gravity, moving ice
Which ELEMENT of the weather is mostly responsible for the mechanical breaking down of rocks
TEMEPERATE/ chnage in temperature
What is the NAME of the rock in the Caribbean is mostly to be weathering by the process of chemical weathering?
Limestone-sedimentary rock
What pulls pieces of rock or sediment down to a new location on the earth.
Gravity
What are the two main types of weathering?
physical/mechanical and chemical
What is Deposition?
When broken down rocks materials are layed down.
What type of rocks are mostly to experience pressure release?
IGENOUS ROCKS
Granite-Intrusive Plutonic Rocks (Batholith) underground.
Chemical Weathering is MOSTLY COMMON in which type of climate
Wet and Humid
Warm, humid and wet
Humid Tropical regions
Why can't the cycle of weathering, erosion, and deposition be stopped?
The erosion cycle is part of nature. Humans can't stop it, but we can help slow it down.
What does in-situ means?
in that place
in its original position
While driving along the highway North-South heading to Kingston, I noticed huge rocks along the highway. Large nets covered these rocks and seemed to go from the top to the bottom. Were these nets put in place to stop weathering or erosion?
Erosion: even when rocks become broken they can not be carried or moved to another location
Explain the process of Frost Action/Freeze-Thaw/ Frost Wedging in breaking down rocks.
1.When water sinks into cracks in a rock and the temperature drops low enough, the water freezes into ice.
2.The ice expands and forms wedges in the rock that can split the rock into smaller fragments. Ice wedging usually occurs after water repeatedly freezes and melts inside small rock crevices over time.
Explain CARBONATION is the breaking of rocks.
First rainwater reacts with carbon dioxide in the air to form Carbonic acid.
•The carbonic acid then reacts with the calcium carbonate in the rock to form calcium bicarbonate (calcium hydrogen carbonate).
•This stage is very important because, Calcium Carbonate is not soluble in water.
•However, Calcium Bi-Carbonate is soluble in water.
This means that when Calcium Bi-Carbonate is formed, the final stage is when it is removed in solution.
Give and example of water erosion
An example of water erosion is when a river pulls sediment and small rocks from the riverbanks and carries it all down stream to another place.
'The rate/degree of weathering depends on certains factors'.
Name ANY TWO factors that influences the rate of weathering.
1. the structure and mineral composition of the rocks,
2. the local climate and vegetation,
3. and the length of time during which the weathering processes takes place
What is Denudatiom?
The wearing away of the landscape
Explain the process of Thermal Expansion/Temperature Change in the breaking down of rocks
Rocks are broken up into smaller pieces by extreme temperatures!
High temperatures during the day results in the surface of the rocks to expand.
Rapid cooling at nights causes the surface of the rocks to contract.
The repeated expansion and contraction cauases the cracks on the surface of the rocks to break apart grain by grain and peel of-exfoliation.
Explain HYDROLYSIS in the breaking down of granite rocks?
qThe most common example of a hydrolysis is feldspar, which can be found in granite changing to clay.
qWhen it rains. water seeps down into the ground and comes in contact with granite rocks.
qThe Feldspar crystals within the granite react with the water and are chemically altered to form clay minerals, which weaken the rock.
What is an example of ice erosion
An example is when a glacier scrapes rock and sediment as it moves down hill, and leaves it in a different location