Weathering and Erosion

Weathering

There are three types of weathering

• Physical Weathering
• Biological Weathering
• Chemical Weathering

What is weathering?
Weathering is the breaking down/wearing away of rocks over time.

Physical  Weathering

What is it?
Physical weathering is the breaking down of rocks caused by physical features such as temperature, wind, and water.

Physical weathering by water happens when water continuously hits or washes over the rocks, breaking them down and making them smooth.

Physical weathering by temperature or freezing and thawing can happen when rocks continuously freeze and thaw, the rock will crack causing the outer layers to break off.

This is a picture of physical weathering because it shows examples of this rock contrasting and expanding over time,from temperature change. When a rock contasts and expands for a long period of time,the rock will start to wear away and crack. Like this.

Biological Weathering

What is biological weathering?
Biological weathering is the wearing away of rocks due to living things such as plants and animals.

An example of biological weathering by plants is when you are outside and you see grass or trees growing through cement or pavement. An example of biological weathering due to animals is when small animals such as bunnies burrow into the ground causing rocks around them to split and crack.

This is a photo of biological weathering because it shows example of show people put rocks with netting over a mud slide/cliff to prevent anymore cliffs falling.

Chemical Weathering

What is chemical weathering?
Chemical weathering is the breaking down of rocks/sediment due to chemicals.

How does it happen?
Chemical weathering can happen by oxidation, or air pollution. Oxidation is breaking down by water and oxygen. The air pollution pollutes rain water, and that rain water breaks down rocks, especially limestone and chalk.

This is a photo of chemical weathering and it show examples of rust on a rock,the rust got there from rain water. Rain water has some acid in it so when it rains the rain can make a chemical reaction with some rocksmost likely limestone. Another thing that could happen to the rocks is that from the rain water the rock can start to wear away which is why there is some holes in the rock

Erosion

What is erosion?
Erosion is the moving around or rock pieces or sediment after they are broken down, or weathered.

Erosion by Wind

How does erosion by wind occur?
Erosion by wind happens when the wind picks up or pushes and pulls small clay-sand sized pieces of sediment such as sand, ash, and dust, and move them to a new location. This type of erosion happens in many sandy areas such as deserts.

What impacts does it have on land forms?

• Erosion by wind can create sand dunes by pushing it against each other.
• The wind can pick up small pieces of topsoil from farms.
• Wind has even taken out some mountains by blowing it over.

This is an example of Erosion by wind because it shows the different sand particals that were moved across the sand. Which makes a pattern or effect in the sand.

Erosion by water

How does erosion by water happen?
Erosion by water happens when moving rivers or rain water currents take sediment from their original place downstream to a new location. The size of the rock pieces that are able to be moved depend on the speed of the current. Most rainwater streams only take small, clay-sand sized pieces, but fast moving rivers can carry very large boulders. It also happens when waves wash onto shore then take rocks back into the water, then push them up again back onto the beach or anywhere the water washes up.

How does this impact other landforms?
Erosion by water can cause abrasion, which is wearing away of stream bed and backs causing them to become much deeper over a long period of time. Water can also cause erosion by carving out valleys and canyons, as well as build things up to make a delta.

This is a photo of erosion by water and it is an example of erosioin by water because a coastline moves sediments around either in or out of the lake,ocean,river or stream.

Erosion by Glaciers

How does erosion by glaciers/ice occur?
This happens when large sheets of ice move slowly down hill around land. When the glaciers move, the pick up anything and everything in their path. The sediment either gets pushed/plowed in front of the glacier, or get stuck inside even if they are massive boulders or just tiny pebbles.

What impacts do glaciers have on land forms?
Erosion by glaciers can make very huge effects on land. They shape coastlines on oceans and lakes, and form them. Glaciers can also cause mountains to be formed, as well as carve valleys and canyons. They can also straight up erode the land down. There was even a time in history called the ice age, when many large areas around the world were just completely covered in ice and glaciers.

What impacts do glaciers have on land forms?
Erosion by glaciers can make very huge effects on land. They shape coastlines on oceans and lakes, and form them. Glaciers can also cause mountains to be formed, as well as carve valleys and canyons. They can also straight up erode the land down. There was even a time in history called the ice age, when many large areas around the world were just completely covered in ice and glaciers.

This is a photo of erosion by gravity and it is an example of erosion by gravity because it shows how there was once a glacier here but it moved down hill and picked up everything that was in its path. Which leaves a cliff like landform here.

Erosion by Gravity

How does erosion by gravity happen?
Many times after rocks are weathered and broken on hillsides or cliffs, gravity will pull them all down toward the Earth's surface no matter what the size. It can also happen when rain or snow sink into the rocks which causes more pressure causing it to fall to the lowest point near it. Earthquakes are another way known to cause gravity to pull rocks down. Erosion by gravity is also known as mass wasting.

What effects does erosion by gravity have on other landforms?
It can cause very large landslides, which can erode an area greatly, as well as cause even more pieces of rock to break and/or fall down with the others already falling.

This is a cliff. This is an example of gravity by erosion because it used to be all filled in, but over time, gravity pulled the chunk of land down.

Some people have taken steps to try and prevent more weathering and eriosion from happening. People have put in nets and extra mud to prevent mud and landslides.

This is an example on how people are trying to stop erosion by gravity. They put netting and mud on a hill where the hill could pottentially fall off.

Citations

• BBC
• Eschool
• DE
• National Geographic
• Ducksters