# data[].attributes.body
Chloe Uenishi
1. particles in rocks can wear away
2. oceans break apart rocks to make sand
3. weathering and erosion are much different
questions
1. what are fragments?
2. whats the difference between weathering and erosion?
3. what wears down surfaces?

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What I Learned
1. Physical erosion changes a rock's physical property
2. Chemical erosion changes a rock's chemical composition
3. The Grand Canyon was formed over millions of years by erosion
Questions
1. How does gravity break down rock?
2. How do humans contribute to erosion?
Why I Picked it
I saw National Geographic after searching and I knew it would be reliable.

# data[].attributes.body
(things I learned)
1. I learned that erosion can have strange effects.
2. I learned that there are multiple kinds of erosion
3. I learned that the sun itself is a factor of erosion.
(questions I have)
1. How exactly does erosion erode only some parts of rock (like the Arches)?
2. Can a rock be eroded without being weathered?
(reason)
I googled "erosion article" and National Geographic was the 1st reliable one I found.

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Erosion is the geological process in which earthen materials are worn away and transported by natural forces such as wind or water. A similar process, weathering, breaks down or dissolves rock, but does not involve movement. Erosion is the opposite of deposition, the geological process in which earthen materials are deposited, or built up, on a landform. Most erosion is performed by liquid water, wind, or ice (usually in the form of a glacier). If the wind is dusty, or water or glacial ice is muddy, erosion is taking place. The brown color indicates that bits of rock and soil are suspended in the fluid (air or water) and being transported from one place to another. This transported material is called sediment.

Physical erosion describes the process of rocks changing their physical properties without changing their basic chemical composition. Physical erosion often causes rocks to get smaller or smoother. Rocks eroded through physical erosion often form clastic sediments. Clastic sediments are composed of fragments of older rocks that have been transported from their place of origin. Landslides and other forms of mass wasting are associated with physical weathering. These processes cause rocks to dislodge from hillsides and crumble as they tumble down a slope.

Plant growth can also contribute to physical erosion in a process called bioerosion. Plants break up earthen materials as they take root, and can create cracks and crevices in rocks they encounter. Ice and liquid water can also contribute to physical erosion as their movement forces rocks to crash together or crack apart. Some rocks shatter and crumble, while others are worn away. River rocks are often much smoother than rocks found elsewhere, for instance, because they have been eroded by constant contact with other river rocks.

Erosion by Water

Liquid water is the major agent of erosion on Earth. Rain, rivers, floods, lakes, and the ocean carry away bits of soil and sand and slowly wash away the sediment. Rainfall produces four types of soil erosion: splash erosion, sheet erosion, rill erosion, and gully erosion.

Splash erosion describes the impact of a falling raindrop, which can scatter tiny soil particles as far as 0.6 meters (two feet).

Sheet erosion describes erosion caused by runoff.

Rill erosion describes erosion that takes place as runoff develops into discrete streams (rills).

Finally, gully erosion is the stage in which soil particles are transported through large channels.

The Fish River Canyon, in southern Namibia, is the largest canyon in Africa and a product of valley erosion. Over millions of years, the Fish River wore away at the hard gneiss bedrock, carving a canyon about 160 kilometers (99 miles) in length, 27 kilometers (17 miles) wide, and 550 meters (1,084 feet) deep.

The battering force of ocean waves also erodes seaside cliffs. The action of erosion can create an array of coastal landscape features. For example, erosion can bore holes that form caves. When water breaks through the back of the cave, it can create an arch. The continual pounding of waves can cause the top of the arch to fall, leaving nothing but rock columns called sea stacks. The seven remaining sea stacks of Twelve Apostles Marine National Park, in Victoria, Australia, are among the most dramatic and well-known of these features of coastal erosion.

Erosion by Wind

Erosion by Ice

Ice, usually in the form of glaciers, can erode the earth and create dramatic landforms. In frigid areas and on some mountaintops, glaciers move slowly downhill and across the land. As they move, they transport everything in their path, from tiny grains of sand to huge boulders. Rocks carried by glaciers scrape against the ground below, eroding both the ground and the rocks. In this way, glaciers grind up rocks and scrape away the soil. Moving glaciers gouge out basins and form steep-sided mountain valleys. Eroded sediment called moraine is often visible on and around glaciers.

Several times in Earth's history, vast glaciers covered parts of the Northern Hemisphere. These glacial periods are known as ice ages. Ice Age glaciers carved much of the modern northern North American and European landscape. Ice Age glaciers scoured the ground to form what are now the Finger Lakes in the U.S. state of New York, for example. They carved fjords, deep inlets along the coast of Scandinavia. The snout of a glacier eroded Cape Cod Bay, Massachusetts, U.S., and formed the recognizable fishhook shape of Cape Cod itself.

Today, in places such as Greenland and Antarctica, glaciers continue to erode the earth. Ice sheets there can be more than a mile thick, making it difficult for scientists to measure the speed and patterns of erosion. However, ice sheets do erode remarkably quickly-as much as half a centimeter (0.2 inch) every year.

Other Forces of Erosion

Factors Impacting Erosion

Some of the natural factors impacting erosion in a landscape include climate, topography, vegetation, and tectonic activity. Climate is perhaps the most influential force impacting the effect of erosion on a landscape. Climate includes precipitation and wind. Climate also includes seasonal variability, which influences the likelihood of weathered sediments being transported during a weather event such as a snowmelt, breeze, or hurricane. Topography, the shape of surface features of an area, can contribute to how erosion impacts that area. The earthen floodplains of river valleys are much more prone to erosion than rocky flood channels, which may take centuries to erode. Soft rock like chalk will erode more quickly than hard rocks like granite.

Vegetation can slow the impact of erosion. Plant roots adhere to soil and rock particles, preventing their transport during rainfall or wind events. Trees, shrubs, and other plants can even limit the impact of mass wasting events such as landslides and other natural hazards such as hurricanes. Deserts, which generally lack thick vegetation, are often the most eroded landscapes on the planet.

Finally, tectonic activity shapes the landscape itself, and thus influences the way erosion impacts an area. Tectonic uplift, for example, causes one part of the landscape to rise higher than others. In a span of about 5 million years, tectonic uplift caused the Colorado River to cut deeper and deeper into the Colorado Plateau, land in what is now the U.S. state of Arizona. It eventually formed the Grand Canyon, which is more than 1,600 meters (one mile) deep and as much as 29 kilometers (18 miles) wide in some places.

Erosion and People
Deposition, Soils, and Sediments
Eroded sediments have profoundly influenced the development of civilizations around the world. Agricultural development is often reliant on the nutrient-rich soils created by the accumulation of eroded earth. When the velocity of wind or water slows, eroded sediment is deposited in a new location. The sediment builds up in a process called sedimentation and creates fertile land. River deltas are made almost entirely of sediment that has eroded from the banks and bed of a river.

The rich delta soils of the San Joaquin and Sacramento rivers in northern California, for example, have created one of the most agriculturally productive areas in the world. Loess is an agriculturally rich sediment made almost entirely of wind-blown, eroded sediment.

The Yellow River in central China gets its name from the yellow loess blown into and suspended in its water. The fertile lands around the Yellow River have been among China's most productive for thousands of years.

Erosion is a natural process, but human activity can make it happen more quickly. Human activity altering the vegetation of an area is perhaps the biggest human factor contributing to erosion. Trees and plants hold soil in place. When people cut down forests or plow up grasses for agriculture and development, the soil is more vulnerable to washing or blowing away. Landslides become more common. Water rushes over exposed soil rather than soaking into it, causing flooding.

The rise in temperature is also quickly melting glaciers. The slower, more massive form of glacial erosion is being supplanted by the cumulative impact of rill, gully, and valley erosion. In areas downstream from glacial snouts, rapidly melting glaciers are contributing to sea level rise. The rising sea erodes beaches more quickly.

Erosion control is the process of reducing erosion by wind and water. Farmers and engineers must regularly practice erosion control. Sometimes, engineers simply install structures to physically prevent soil from being transported. Gabions are huge wireframes that hold boulders in place, for instance. Gabions are often placed near cliffs. These cliffs, often near the coast, have homes, businesses, and highways near them. When erosion by water or wind threatens to tumble the boulders toward buildings and cars, gabions protect landowners and drivers by holding the rocks in place.

Living shorelines are another form of erosion control in wetland areas. Living shorelines are constructed by placing native plants, stone, sand, and even living organisms such as oysters along wetland coasts. These plants help anchor the soil to the area, preventing erosion. By securing the land, living shorelines establish a natural habitat. They protect coastlines from powerful storm surges as well as erosion.

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Erosion is the geological process in which earthen materials are worn away and transported by natural forces such as wind or water.

# data[].attributes.body
1. how ice breaks rock
2. water dampens then breaks the rocks
3. plants weather things

Q1. how do plants break through rock
Q2. how does wind break things down

reason
It was the only thing I could find that wasn't already used

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Erosion and Weathering for Kids -Causes and Differences

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Natalie Thomas

What I Learned

1. I learned how cracks in the road are formed.
2. I learned how as riverbed was formed
3.You can use a stream of water to cut through hard rocks.

Questions

1. How do cracks form in the road?

2. What happens when pieces of the Earth move till they are deposited?

Why I Picked This

I picked this because it looked like you could actually learn stuff and they do projects to show you.

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What you will learn from this video What you will learn

The Earth's surface gets broken down through weathering.

Small pieces of the Earth get moved through erosion.

The small pieces are deposited somewhere else through a process called deposition.

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Describe 3 forces of nature that cause weathering.

What are the differences between weathering, erosion and deposition?

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Learn about weathering, erosion & deposition! Our science video for kids teaches you how these forces of nature shape the surface of the earth! Watch now!

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1. That there are many different processes in earth and the ocean. ( like the rock cycle )

2. The Rockies and the alps were strong enough to change climate change.

3. Caves are formed by dead animals and rocks.

Questions

1. What causes the rock cycle?

2. Why are there different types of weathering?

Reason

Because I think weathering and thought it might be interresting

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What is Weathering? Crash Course Geography #22

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im bread (brendan) and this is the vid i found

1 i learned that rocks are constntly changing

2 i learned that air can break rocks

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1. Wind, sand, and waves wash up rocks to make them erode.
2. A rock from one day will always be different the next day.
3. Erosion never stops

1. Are there any rocks that can't erode?
2. Was all sand everywhere once sand?

1. It is Bill Nye, a lot of teachers use it.

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Bill Nye the Science Guy - S05E14 Erosion

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1.) Weathering and erosion causes a sedimentary rock.

2.) Weathering breaks down the rocks.

3.) Weathering is so important because its the principal source of inorganic material soil, and they need that so that they can grow vegetation.

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What is Weathering? Crash Course Geography #22

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https://clarkscience8.weebly.com/weathering-erosion-deposition.html

3a: Weathering/Erosion/Deposition rusts metal.
3b: Wind and water cause deposition
3c: Forms deltas

2a: How does the processes cause metals to rust?
2b: How fast is deposition?

1: I chose an article because not a lot of people were doing articles and I chose this one because it looked reliable. (I also didn't choose any at the top, because I knew that's what everyone would do. I scrolled farther down to a site no-one would get.

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1. I learned that Erosion caused by rain or irrigation can wash away soil. I also learned If the pieces of weathered rock are moved away, it is called erosion. The last thing I learned was Weathering may be caused by the action of water, air, chemicals, plants, or animals.
2. Does weathering and erosion happen a lot?, How many different types of erosion are there?
3. I chose this article because it showed all of the kinds of erosions.

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https://www.youtube.com/watch?v=qGw1yB10lX0
1. sand is an example of erosion
2. Abrasion is physical weathering
3. rust can weaken rock
1. how long does it takes for a cave to form
2.how does rain fall create erosion
I chose this video because it is easier for me to learn by watching something than reading something because i don't always remember things that i read

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Difference between Weathering and Erosion

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1. There are different types of Erosion that are differentiated by the force that carries rock or soil.
2. There is a specific type of erosion called Mass wasting and its caused by gravity.
3.  Weathering breaks down a rock without moving it.

Questions:
1. What is the difference between weathering and erosion?
2. What is the difference between Chemical and Physical weathering?

I chose this article because i feel like  it does a good job of explaining what weathering and erosion and the different types  of each in good detail.

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​ Weathering​ and ​ erosion ​ are processes by which rocks are broken down and moved from their original location. The difference between weathering and erosion is based on whether a rock's location has changed: Weathering degrades a rock without moving it, while erosion carries rocks and soil away from their original locations. Weathering often leads to erosion by causing rocks to break down into smaller pieces, which erosive forces can then move away.

TL;DR (Too Long; Didn't Read)

Weathering and erosion are sometimes use interchangeably, but they're different. ​ Weathering​ breaks large rocks into smaller pieces, while ​ erosion ​ moves those pieces away from the original rock.

The main difference between weathering and erosion lies in where the process takes place. Weathering degrades a rock without changing its location. Erosion, on the other hand, causes rocks - or particles of rock - to be carried away from their original locations and deposited elsewhere. Weathering often leads to erosion, breaking down the rock into small pieces that are easier for wind and water to carry away.

​ Wind abrasion ​ is an example of a process that includes both weathering and erosion. Wind picks up small pieces of rock and blows them against larger stones, causing small particles of the larger formations to break off - this is weathering. The same wind picks up these particles and takes them away from the rock they broke off of - this is erosion.

There are two distinct types of weathering, which alter and degrade rock in different ways. ​ Physical weathering ​ breaks down a rock's physical structure. For example, in cold environments water that gets into holes in rock and freezes will cause those holes to expand and eventually crack and split the rock.

The same process may be caused by salt buildup or growing tree roots. Another form of physical weathering occurs when wind or water causes rocks to rub against each other, smoothing their surfaces.

​ Chemical weathering ​ changes the chemical structure of rock, causing it to become softer or more brittle. For example, iron in a rock might react with oxygen to form easily degradable rust, or acids in rainwater may remove calcium from limestone and marble. Chemical weathering often precedes physical weathering, making rocks more vulnerable to forces like wind and rain.

Different types of erosion are usually differentiated by the force that carries rock, stone or soil away from its location. Water is the most common force that causes erosion. Rivers wear down and carry away rock and soil along their banks. The Grand Canyon was formed from millions of years of this sort of erosion. Similar erosion occurs in the ocean, where moving water and waves degrade and carry away particles of coastline rock.

Wind erosion can only occur on smaller particles of ash, dust and rock, but it can still move large quantities of these particles from their original locations and create impressive formations, such as sand dunes.

Erosion by ice is rare in most parts of the world, but ice can move much larger rocks than most other erosive forces. Ice may carry huge boulders miles away from their original locations.

​ Mass wasting ​ is a specific type of erosion that is caused by gravity. Mass wasting occurs when soil or rocks are carried away - not by wind or water - but by falling or sliding downwards.

A ​ rockslide​ or ​ landslide​ is a common example of mass wasting, as a large quantity of loose rock or soil rolls or slides down a slope. ​ Rock falls ​ occur when loose rock splits off from high cliffs. Mass wasting may also cause physical weathering by causing rocks to shatter upon hitting the ground or causing rocks to rub against each other while rolling and sliding.

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The Difference Between Weathering & Erosion

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Weathering and erosion are sometimes use interchangeably, but they're different. The difference between weathering and erosion has to do with location: Weathering breaks large rocks into smaller pieces without moving the rock, while erosion moves the pieces of rock away from their original location.

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1. Weathering can be caused by 5 different things.
2. There are two types of Weathering.
3. Moving water is a part of Erosion.
1. Why is there so much stuff about Weathering.
2. How does Weathering and Erosion affect humans.
1. I chose this resource because this video was very informational and it helped me make this Padlet.

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Weathering and Erosion: Crash Course Kids #10.2

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https://www.youtube.com/watch?v=ewj629B4Oe8
1. Erosion made the Grand Canyon
2.  another name for erosion is corrosion.
3. Sir Charles Lyell Discovered erosion.
1. Does how deep the rocks are matter for erosion?
2. Is there another part after Weathering that happens?
I chose this website because it was very informative.

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Weathering, Erosion, and Deposition [Part 1]

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1.) The rocks that are eroded by physical erosion usually form Clastic Sediments.

2.) Landslides are a form of Mass Wasting.

3.)  Plant erosion helps with a form of physical erosion called bioerosion.

1.) How many different kinds of erosion is there?

2.) How often is erosion hurtful to the environment or in growing stuff?

I chose this website because it was one of the first links that was not Wikipedia and it is also from National Geographic and National Geographic is very trustworthy and helpful.

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Erosion is the geological process in which earthen materials are worn away and transported by natural forces such as wind or water. A similar process, weathering, breaks down or dissolves rock, but does not involve movement. Erosion is the opposite of deposition, the geological process in which earthen materials are deposited, or built up, on a landform. Most erosion is performed by liquid water, wind, or ice (usually in the form of a glacier). If the wind is dusty, or water or glacial ice is muddy, erosion is taking place. The brown color indicates that bits of rock and soil are suspended in the fluid (air or water) and being transported from one place to another. This transported material is called sediment.

Physical erosion describes the process of rocks changing their physical properties without changing their basic chemical composition. Physical erosion often causes rocks to get smaller or smoother. Rocks eroded through physical erosion often form clastic sediments. Clastic sediments are composed of fragments of older rocks that have been transported from their place of origin. Landslides and other forms of mass wasting are associated with physical weathering. These processes cause rocks to dislodge from hillsides and crumble as they tumble down a slope.

Plant growth can also contribute to physical erosion in a process called bioerosion. Plants break up earthen materials as they take root, and can create cracks and crevices in rocks they encounter. Ice and liquid water can also contribute to physical erosion as their movement forces rocks to crash together or crack apart. Some rocks shatter and crumble, while others are worn away. River rocks are often much smoother than rocks found elsewhere, for instance, because they have been eroded by constant contact with other river rocks.

Erosion by Water

Liquid water is the major agent of erosion on Earth. Rain, rivers, floods, lakes, and the ocean carry away bits of soil and sand and slowly wash away the sediment. Rainfall produces four types of soil erosion: splash erosion, sheet erosion, rill erosion, and gully erosion.

Splash erosion describes the impact of a falling raindrop, which can scatter tiny soil particles as far as 0.6 meters (two feet).

Sheet erosion describes erosion caused by runoff.

Rill erosion describes erosion that takes place as runoff develops into discrete streams (rills).

Finally, gully erosion is the stage in which soil particles are transported through large channels.

The Fish River Canyon, in southern Namibia, is the largest canyon in Africa and a product of valley erosion. Over millions of years, the Fish River wore away at the hard gneiss bedrock, carving a canyon about 160 kilometers (99 miles) in length, 27 kilometers (17 miles) wide, and 550 meters (1,084 feet) deep.

The battering force of ocean waves also erodes seaside cliffs. The action of erosion can create an array of coastal landscape features. For example, erosion can bore holes that form caves. When water breaks through the back of the cave, it can create an arch. The continual pounding of waves can cause the top of the arch to fall, leaving nothing but rock columns called sea stacks. The seven remaining sea stacks of Twelve Apostles Marine National Park, in Victoria, Australia, are among the most dramatic and well-known of these features of coastal erosion.

Erosion by Wind

Erosion by Ice

Ice, usually in the form of glaciers, can erode the earth and create dramatic landforms. In frigid areas and on some mountaintops, glaciers move slowly downhill and across the land. As they move, they transport everything in their path, from tiny grains of sand to huge boulders. Rocks carried by glaciers scrape against the ground below, eroding both the ground and the rocks. In this way, glaciers grind up rocks and scrape away the soil. Moving glaciers gouge out basins and form steep-sided mountain valleys. Eroded sediment called moraine is often visible on and around glaciers.

Several times in Earth's history, vast glaciers covered parts of the Northern Hemisphere. These glacial periods are known as ice ages. Ice Age glaciers carved much of the modern northern North American and European landscape. Ice Age glaciers scoured the ground to form what are now the Finger Lakes in the U.S. state of New York, for example. They carved fjords, deep inlets along the coast of Scandinavia. The snout of a glacier eroded Cape Cod Bay, Massachusetts, U.S., and formed the recognizable fishhook shape of Cape Cod itself.

Today, in places such as Greenland and Antarctica, glaciers continue to erode the earth. Ice sheets there can be more than a mile thick, making it difficult for scientists to measure the speed and patterns of erosion. However, ice sheets do erode remarkably quickly-as much as half a centimeter (0.2 inch) every year.

Other Forces of Erosion

Factors Impacting Erosion

Some of the natural factors impacting erosion in a landscape include climate, topography, vegetation, and tectonic activity. Climate is perhaps the most influential force impacting the effect of erosion on a landscape. Climate includes precipitation and wind. Climate also includes seasonal variability, which influences the likelihood of weathered sediments being transported during a weather event such as a snowmelt, breeze, or hurricane. Topography, the shape of surface features of an area, can contribute to how erosion impacts that area. The earthen floodplains of river valleys are much more prone to erosion than rocky flood channels, which may take centuries to erode. Soft rock like chalk will erode more quickly than hard rocks like granite.

Vegetation can slow the impact of erosion. Plant roots adhere to soil and rock particles, preventing their transport during rainfall or wind events. Trees, shrubs, and other plants can even limit the impact of mass wasting events such as landslides and other natural hazards such as hurricanes. Deserts, which generally lack thick vegetation, are often the most eroded landscapes on the planet.

Finally, tectonic activity shapes the landscape itself, and thus influences the way erosion impacts an area. Tectonic uplift, for example, causes one part of the landscape to rise higher than others. In a span of about 5 million years, tectonic uplift caused the Colorado River to cut deeper and deeper into the Colorado Plateau, land in what is now the U.S. state of Arizona. It eventually formed the Grand Canyon, which is more than 1,600 meters (one mile) deep and as much as 29 kilometers (18 miles) wide in some places.

Erosion and People
Deposition, Soils, and Sediments
Eroded sediments have profoundly influenced the development of civilizations around the world. Agricultural development is often reliant on the nutrient-rich soils created by the accumulation of eroded earth. When the velocity of wind or water slows, eroded sediment is deposited in a new location. The sediment builds up in a process called sedimentation and creates fertile land. River deltas are made almost entirely of sediment that has eroded from the banks and bed of a river.

The rich delta soils of the San Joaquin and Sacramento rivers in northern California, for example, have created one of the most agriculturally productive areas in the world. Loess is an agriculturally rich sediment made almost entirely of wind-blown, eroded sediment.

The Yellow River in central China gets its name from the yellow loess blown into and suspended in its water. The fertile lands around the Yellow River have been among China's most productive for thousands of years.

Erosion is a natural process, but human activity can make it happen more quickly. Human activity altering the vegetation of an area is perhaps the biggest human factor contributing to erosion. Trees and plants hold soil in place. When people cut down forests or plow up grasses for agriculture and development, the soil is more vulnerable to washing or blowing away. Landslides become more common. Water rushes over exposed soil rather than soaking into it, causing flooding.

The rise in temperature is also quickly melting glaciers. The slower, more massive form of glacial erosion is being supplanted by the cumulative impact of rill, gully, and valley erosion. In areas downstream from glacial snouts, rapidly melting glaciers are contributing to sea level rise. The rising sea erodes beaches more quickly.

Erosion control is the process of reducing erosion by wind and water. Farmers and engineers must regularly practice erosion control. Sometimes, engineers simply install structures to physically prevent soil from being transported. Gabions are huge wireframes that hold boulders in place, for instance. Gabions are often placed near cliffs. These cliffs, often near the coast, have homes, businesses, and highways near them. When erosion by water or wind threatens to tumble the boulders toward buildings and cars, gabions protect landowners and drivers by holding the rocks in place.

Living shorelines are another form of erosion control in wetland areas. Living shorelines are constructed by placing native plants, stone, sand, and even living organisms such as oysters along wetland coasts. These plants help anchor the soil to the area, preventing erosion. By securing the land, living shorelines establish a natural habitat. They protect coastlines from powerful storm surges as well as erosion.

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Erosion is the geological process in which earthen materials are worn away and transported by natural forces such as wind or water.

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1. weathering destroys the earth and creates something new like anions and bays. there are 3 main types of weathering, chemical weathering, mechanical, and biological weathering.
2. weathering breaks down rok on the earth's surface.
3. the grand canyon was formed by erosion over millions of years.

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Weathering and Erosion | What Is the Difference between Weathering and Erosion?

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3. I learned there are 3 types of weathering Physical, chemical, and organic. I learned its the carry of dissolving of rock into sediment ''its'' (erosion and weathering. the third thing i learned is physical weathering is breaking down the rocks structure.

2. How long would it take to weather a rock bigger than a house. And how long would it take to weather/erode a creek into a river.

1. I chose this website because it provided me with plenty of information for this padlet. And had many extra info i did not mention

https://www.youtube.com/watch?v=o-fdvO8gU2k

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WEATHERING AND EROSION || SCIENCE VIDEO FOR KIDS

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Ahaan A. (totally the 3rd ahaan in ur class)

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Ahaan A. (totally the 3rd ahaan in ur class)

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https://courses.lumenlearning.com/wmopen-geology/chapter/outcome-weathering-and-erosion/

Link ↑

1a. Acid Rain is a type of weathering.

1b. Ice wedging is the most common type of weathering.

1c. The Appalachian mountains were as big as the Himalayas but weathering changed that.

2a. Is lava a type of weathering?

2b. If my house was a rock, would it eventually not be there because of weathering and erosion?

3a. I chose this resource because it looked interesting, like the pictures were good and at the end, there was a quiz. I also skimmed through it at first and the information looked accurate and descriptive.

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Describe types and processes of weathering and erosion.

This section introduces you to weathering and erosion, both important parts of the rock cycle. You will learn how different rocks are weathered and eroded and the implications of this weathering.

What You'll Learn to Do

Identify the ways mechanical weathering alters materials on Earth.

Identify the ways chemical weathering alters materials on Earth.

Identify several influences on weathering.

What Is Weathering?

The footprints that astronauts left on the Moon will be there forever. Why? This is because the Moon has no atmosphere and, as a result, has no weathering. Weathering is one of the forces on Earth that destroy rocks and landforms. Without weathering, geologic features would build up but would be less likely to break down.

Weathering is the process that changes solid rock into sediments. Sediments were described in the Rocks chapter. With weathering, rock is disintegrated. It breaks into pieces.

Once these sediments are separated from the rocks, erosion is the process that moves the sediments. Erosion is the next chapter's topic. The four forces of erosion are water, wind, glaciers, and gravity.

Water is responsible for most erosion. Water can move most sizes of sediments, depending on the strength of the force.

Wind moves sand-sized and smaller pieces of rock through the air.

Glaciers move all sizes of sediments, from extremely large boulders to the tiniest fragments.

Gravity moves broken pieces of rock, large or small, downslope.

While plate tectonics forces work to build huge mountains and other landscapes, the forces of weathering gradually wear those rocks and landscapes away. Together with erosion, tall mountains turn into hills and even plains. The Appalachian Mountains along the east coast of North America were once as tall as the Himalayas.

No human being can watch for millions of years as mountains are built, nor can anyone watch as those same mountains gradually are worn away. But imagine a new sidewalk or road. The new road is smooth and even. Over hundreds of years, it will completely disappear, but what happens over one year? What changes would you see (figure 1)? What forces of weathering wear down that road, or rocks or mountains over time?

Follow this link to view some animations of different types of weathering processes.

Mechanical Weathering

Mechanical weathering (also called physical weathering) breaks rock into smaller pieces. These smaller pieces are just like the bigger rock, just smaller. That means the rock has changed physically without changing its composition. The smaller pieces have the same minerals, in just the same proportions as the original rock.

There are many ways that rocks can be broken apart into smaller pieces. Ice wedging is the main form of mechanical weathering in any climate that regularly cycles above and below the freezing point (figure 2). Ice wedging works quickly, breaking apart rocks in areas with temperatures that cycle above and below freezing in the day and night, and also that cycle above and below freezing with the seasons.

Ice wedging breaks apart so much rock that large piles of broken rock are seen at the base of a hillside, as rock fragments separate and tumble down. Ice wedging is common in Earth's polar regions and mid latitudes, and also at higher elevations, such as in the mountains. Abrasion is another form of mechanical weathering. In abrasion, one rock bumps against another rock.

Gravity causes abrasion as a rock tumbles down a mountainside or cliff.

Moving water causes abrasion as particles in the water collide and bump against one another.

Strong winds carrying pieces of sand can sandblast surfaces.

Ice in glaciers carries many bits and pieces of rock. Rocks embedded at the bottom of the glacier scrape against the rocks below.

Abrasion makes rocks with sharp or jagged edges smooth and round. If you have ever collected beach glass or cobbles from a stream, you have witnessed the work of abrasion (figure 3).

Now that you know what mechanical weathering is, can you think of other ways it could happen? Plants and animals can do the work of mechanical weathering (figure 4). This could happen slowly as a plant's roots grow into a crack or fracture in rock and gradually grow larger, wedging open the crack. Burrowing animals can also break apart rock as they dig for food or to make living spaces for themselves.

Mechanical weathering increases the rate of chemical weathering. As rock breaks into smaller pieces, the surface area of the pieces increases figure 5. With more surfaces exposed, there are more surfaces on which chemical weathering can occur.

Chemical Weathering

Chemical weathering is the other important type of weathering. Chemical weathering is different from mechanical weathering because the rock changes, not just in size of pieces, but in composition. That is, one type of mineral changes into a different mineral. Chemical weathering works through chemical reactions that cause changes in the minerals.

Most minerals form at high pressure or high temperatures deep in the crust, or sometimes in the mantle. When these rocks reach the Earth's surface, they are now at very low temperatures and pressures. This is a very different environment from the one in which they formed and the minerals are no longer stable. In chemical weathering, minerals that were stable inside the crust must change to minerals that are stable at Earth's surface.

Remember that the most common minerals in Earth's crust are the silicate minerals. Many silicate minerals form in igneous or metamorphic rocks. The minerals that form at the highest temperatures and pressures are the least stable at the surface. Clay is stable at the surface and chemical weathering converts many minerals to clay (figure 6).

There are many types of chemical weathering because there are many agents of chemical weathering. Water is the most important agent of chemical weathering. Two other important agents of chemical weathering are carbon dioxide and oxygen.

Chemical Weathering by Water

A water molecule has a very simple chemical formula, H ₂O, two hydrogen atoms bonded to one oxygen atom. But water is pretty remarkable in terms of all the things it can do. Remember from the Earth's Minerals chapter that water is a polar molecule. The positive side of the molecule attracts negative ions and the negative side attracts positive ions. So water molecules separate the ions from their compounds and surround them. Water can completely dissolve some minerals, such as salt. Follow this link to check out this animation of how water dissolves salt.

Hydrolysis is the name of the chemical reaction between a chemical compound and water. When this reaction takes place, water dissolves ions from the mineral and carries them away. These elements have undergone leaching. Through hydrolysis, a mineral such as potassium feldspar is leached of potassium and changed into a clay mineral. Clay minerals are more stable at the Earth's surface.

Chemical Weathering by Acid Rain

Carbon dioxide (CO ₂) combines with water as raindrops fall through the atmosphere. This makes a weak acid, called carbonic acid. Carbonic acid is a very common in nature where it works to dissolve rock.

Pollutants, such as sulfur and nitrogen, from fossil fuel burning, create sulfuric and nitric acid. Sulfuric and nitric acids are the two main components of acid rain, which accelerate chemical weathering (figure 7). Acid rain is discussed in the Human Actions and the Atmosphere chapter.

Chemical Weathering by Oxygen

Oxidation is a chemical reaction that takes place when oxygen reacts with another element. Oxygen is very strongly chemically reactive. The most familiar type of oxidation is when iron reacts with oxygen to create rust (figure 8). Minerals that are rich in iron break down as the iron oxidizes and forms new compounds. Iron oxide produces the red color in soils.

Now that you know what chemical weathering is, can you think of some other ways chemical weathering might occur? Chemical weathering can also be contributed to by plants and animals. As plant roots take in soluble ions as nutrients, certain elements are exchanged. Plant roots and bacterial decay use carbon dioxide in the process of respiration.

Influences on Weathering

Weathering rates depend on several factors. These include the composition of the rock and the minerals it contains as well as the climate of a region.

Rock and Mineral Type

Different rock types weather at different rates. Certain types of rock are very resistant to weathering. Igneous rocks, especially intrusive igneous rocks such as granite, weather slowly because it is hard for water to penetrate them. Other types of rock, such as limestone, are easily weathered because they dissolve in weak acids.

Rocks that resist weathering remain at the surface and form ridges or hills. Devil's Tower in Wyoming is an igneous rock from beneath a volcano (figure 9). As the surrounding less resistant rocks were worn away, the resistant center of the volcano remained behind.

Different minerals also weather at different rates. Some minerals in a rock might completely dissolve in water but the more resistant minerals remain. In this case, the rock's surface becomes pitted and rough. When a less resistant mineral dissolves, more resistant mineral grains are released from the rock.

Climate

A region's climate strongly influences weathering. Climate is determined by the temperature of a region plus the amount of precipitation it receives. Climate is weather averaged over a long period of time. Chemical weathering increases as:

Temperature increases: Chemical reactions proceed more rapidly at higher temperatures. For each 10oC increase in average temperature, the rate of chemical reactions doubles.

Precipitation increases: More water allows more chemical reactions. Since water participates in both mechanical and chemical weathering, more water strongly increases weathering.

So how do different climates influence weathering? A cold, dry climate will produce the lowest rate of weathering. A warm, wet climate will produce the highest rate of weathering. The warmer a climate is, the more types of vegetation it will have and the greater the rate of biological weathering (figure 10). This happens because plants and bacteria grow and multiply faster in warmer temperatures.

Some resources are concentrated by weathering processes. In tropical climates, intense chemical weathering carries away all soluble minerals, leaving behind just the least soluble components. The aluminum oxide, bauxite, forms this way and is our main source of aluminum ore.

Check Your Understanding

Answer the question(s) below to see how well you understand the topics covered in the previous section. This short quiz does not count toward your grade in the class, and you can retake it an unlimited number of times.

Use this quiz to check your understanding and decide whether to (1) study the previous section further or (2) move on to the next section.

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This section introduces you to weathering and erosion, both important parts of the rock cycle. You will learn how different rocks are weathered and eroded and the implications of this weathering. Identify the ways mechanical weathering alters materials on Earth. Identify the ways chemical weathering alters materials on Earth.

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1.) I learned that a process called haloclasty can break rock. Carbonic acid can dissolve rock. Changes in pressure can also change rocks.
2.) What are the 2 types of weathering? What are any 3 factors that influence weathering?
3. I chose this link because it tells a lot of information.

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Weathering describes the breaking down or dissolving of rocks and minerals on the surface of the Earth. Water, ice, acids, salts, plants, animals, and changes in temperature are all agents of weathering.

Subjects

Earth Science, Geology, Geography, Physical Geography

Weathering describes the breaking down or dissolving of rocks and minerals on the surface of the Earth. Water, ice, acids, salts, plants, animals, and changes in temperature are all agents of weathering. Once a rock has been broken down, a process called erosion transports the bits of rock and mineral away. No rock on Earth is hard enough to resist the forces of weathering and erosion. Together, these processes carved landmarks such as the Grand Canyon, in the U.S. state of Arizona. This massive canyon is 446 kilometers (277 miles) long, as much as 29 kilometers (18 miles) wide, and 1,600 meters (1 mile) deep. Weathering and erosion constantly change the rocky landscape of Earth. Weathering wears away exposed surfaces over time. The length of exposure often contributes to how vulnerable a rock is to weathering. Rocks, such as lavas, that are quickly buried beneath other rocks are less vulnerable to weathering and erosion than rocks that are exposed to agents such as wind and water. As it smoothes rough, sharp rock surfaces, weathering is often the first step in the production of soils. Tiny bits of weathered minerals mix with plants, animal remains, fungi, bacteria, and other organisms. A single type of weathered rock often produces infertile soil, while weathered materials from a collection of rocks is richer in mineral diversity and contributes to more fertile soil. Soils types associated with a mixture of weathered rock include glacial till, loess, and alluvial sediments. Weathering is often divided into the processes of mechanical weathering and chemical weathering. Biological weathering, in which living or once-living organisms contribute to weathering, can be a part of both processes. Mechanical Weathering Mechanical weathering, also called physical weathering and disaggregation, causes rocks to crumble. Water, in either liquid or solid form, is often a key agent of mechanical weathering. For instance, liquid water can seep into cracks and crevices in rock. If temperatures drop low enough, the water will freeze. When water freezes, it expands. The ice then works as a wedge. It slowly widens the cracks and splits the rock. When ice melts, liquid water performs the act of erosion by carrying away the tiny rock fragments lost in the split. This specific process (the freeze-thaw cycle) is called frost weathering or cryofracturing. Temperature changes can also contribute to mechanical weathering in a process called thermal stress. Changes in temperature cause rock to expand (with heat) and contract (with cold). As this happens over and over again, the structure of the rock weakens. Over time, it crumbles. Rocky desert landscapes are particularly vulnerable to thermal stress. The outer layer of desert rocks undergo repeated stress as the temperature changes from day to night. Eventually, outer layers flake off in thin sheets, a process called exfoliation. Exfoliation contributes to the formation of bornhardts, one of the most dramatic features in landscapes formed by weathering and erosion. Bornhardts are tall, domed, isolated rocks often found in tropical areas. Sugarloaf Mountain, an iconic landmark in Rio de Janeiro, Brazil, is a bornhardt. Changes in pressure can also contribute to exfoliation due to weathering. In a process called unloading, overlying materials are removed. The underlying rocks, released from overlying pressure, can then expand. As the rock surface expands, it becomes vulnerable to fracturing in a process called sheeting. Another type of mechanical weathering occurs when clay or other materials near rock absorb water. Clay, more porous than rock, can swell with water, weathering the surrounding, harder rock. Salt also works to weather rock in a process called haloclasty. Saltwater sometimes gets into the cracks and pores of rock. If the saltwater evaporates, salt crystals are left behind. As the crystals grow, they put pressure on the rock, slowly breaking it apart. Honeycomb weathering is associated with haloclasty. As its name implies, honeycomb weathering describes rock formations with hundreds or even thousands of pits formed by the growth of salt crystals. Honeycomb weathering is common in coastal areas, where sea sprays constantly force rocks to interact with salts. Haloclasty is not limited to coastal landscapes. Salt upwelling, the geologic process in which underground salt domes expand, can contribute to weathering of the overlying rock. Structures in the ancient city of Petra, Jordan, were made unstable and often collapsed due to salt upwelling from the ground below. Plants and animals can be agents of mechanical weathering. The seed of a tree may sprout in soil that has collected in a cracked rock. As the roots grow, they widen the cracks, eventually breaking the rock into pieces. Over time, trees can break apart even large rocks. Even small plants, such as mosses, can enlarge tiny cracks as they grow. Animals that tunnel underground, such as moles and prairie dogs, also work to break apart rock and soil. Other animals dig and trample rock aboveground, causing rock to slowly crumble. Chemical Weathering Chemical weathering changes the molecular structure of rocks and soil. For instance, carbon dioxide from the air or soil sometimes combines with water in a process called carbonation. This produces a weak acid, called carbonic acid, that can dissolve rock. Carbonic acid is especially effective at dissolving limestone. When carbonic acid seeps through limestone underground, it can open up huge cracks or hollow out vast networks of caves. Carlsbad Caverns National Park, in the U.S. state of New Mexico, includes more than 119 limestone caves created by weathering and erosion. The largest is called the Big Room. With an area of about 33,210 square meters (357,469 square feet), the Big Room is the size of six football fields. Sometimes, chemical weathering dissolves large portions of limestone or other rock on the surface of the Earth to form a landscape called karst. In these areas, the surface rock is pockmarked with holes, sinkholes, and caves. One of the world's most spectacular examples of karst is Shilin, or the Stone Forest, near Kunming, China. Hundreds of slender, sharp towers of weathered limestone rise from the landscape. Another type of chemical weathering works on rocks that contain iron. These rocks turn to rust in a process called oxidation. Rust is a compound created by the interaction of oxygen and iron in the presence of water. As rust expands, it weakens rock and helps break it apart. Hydration is a form of chemical weathering in which the chemical bonds of the mineral are changed as it interacts with water. One instance of hydration occurs as the mineral anhydrite reacts with groundwater. The water transforms anhydrite into gypsum, one of the most common minerals on Earth. Another familiar form of chemical weathering is hydrolysis. In the process of hydrolysis, a new solution (a mixture of two or more substances) is formed as chemicals in rock interact with water. In many rocks, for example, sodium minerals interact with water to form a saltwater solution. Hydration and hydrolysis contribute to flared slopes, another dramatic example of a landscape formed by weathering and erosion. Flared slopes are concave rock formations sometimes nicknamed "wave rocks." Their c-shape is largely a result of subsurface weathering, in which hydration and hydrolysis wear away rocks beneath the landscape's surface. Living or once-living organisms can also be agents of chemical weathering. The decaying remains of plants and some fungi form carbonic acid, which can weaken and dissolve rock. Some bacteria can weather rock in order to access nutrients such as magnesium or potassium. Clay minerals, including quartz, are among the most common byproducts of chemical weathering. Clays make up about 40% of the chemicals in all sedimentary rocks on Earth. Weathering and People Weathering is a natural process, but human activities can speed it up. For example, certain kinds of air pollution increase the rate of weathering. Burning coal, natural gas, and petroleum releases chemicals such as nitrogen oxide and sulfur dioxide into the atmosphere. When these chemicals combine with sunlight and moisture, they change into acids. They then fall back to Earth as acid rain. Acid rain rapidly weathers limestone, marble, and other kinds of stone. The effects of acid rain can often be seen on gravestones, making names and other inscriptions impossible to read. Acid rain has also damaged many historic buildings and monuments. For example, at 71 meters (233 feet) tall, the Leshan Giant Buddha at Mount Emei, China is the world's largest statue of the Buddha. It was carved 1,300 years ago and sat unharmed for centuries. An innovative drainage system mitigates the natural process of erosion. But in recent years, acid rain has turned the statue's nose black and made some of its hair crumble and fall.

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National Geographic Society

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Last Updated

October 19, 2023

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Weathering describes the breaking down or dissolving of rocks and minerals on the surface of the Earth. Water, ice, acids, salts, plants, animals, and changes in temperature are all agents of weathering.

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1.The weathering is breaking down of rock on the earth's surface.

2.Two types of weathering called physical and chemical weathering.

3.I choose this video because this video talk about the weathering and erosion.

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Difference between Weathering and Erosion

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https://www.youtube.com/watch?v=pmF41T52nJs -To weathering video

1. Mechanical and Chemical weathering are the two types of weathering.

2. Humans have contributed to a lot of chemical weathering.

3. When the rock breaks down into smaller pieces without it being changed by chemicals, it's called mechanical weathering.

1. Is the changing climate affecting the rock cycle?

2. How long does it take for the rock cycle to go through one full loop?

1. I chose 1st video because it's interactive (and it's Bill Nye) and the 2nd video because it is also interactive and gives a lot of examples.

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Bill Nye the Science Guy - S05E14 Erosion

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Karen Doh
1. there are 2 types of weathering  mechanical and chemical.

2. water and oxygen are "referred" to chemical weathering

3. mechanical weathering is weathering using ice and water

4. Is there another type of weathering that wasn't mentioned in this article?

5. For the existing types of weathering there are none where they specifically add pressure to.

6. It was to easy to access and honestly no one had done it yet and i already read through it for a different assignment so i think i used it efficiently.

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1. I learned that trees can push the earth apart. Glaciers used to cover most of the Earth. Earth is always changing.
2. I wonder how long it takes for erosion to finish. I don't understand how a river could turn into a large canyon.
1. I chose it because it looked interesting and the voice was calming.

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Weathering and Erosion - Check123, Video Encyclopedia

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Watch this video and learn all about Weathering and Erosion. Amazing facts about natural phenomena and geology in 1, 2 or 3 minute videos!

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1.) Weathering can also make a rock different colors, the movement of rocks from one place to another is erosion, there are 3 main types of weathering.
2.) Wasn't the whole world made by weathering. Was the sand on the beach once a rock?
3.) I chose this video because the front was animated and I thought it looked cool.

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Weathering and Erosion | What Is the Difference between Weathering and Erosion?

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1.weathering and erosion are very different things

2.the grand canyon was formed over millions of years by the colorado river; this is a form of weathering.

3.wind can create landforms

1.can glaciers move boulders?

2.can  the colorado river eventually erode the earth to the crust?

1.I chose this article because it had detailed information.

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In this article we shall present a brief overview of erosion and mechanical weathering.It is possible to be brief because the erosional processes involved will be discussed at length in subsequent articles, so there is no need to do more than sketch out the topic in brief.

Geologists make a distinction between weathering and erosion: weathering breaks rocks but leaves them in place; whereas the processes of erosion are capable both of breaking rocks and transporting the broken fragments (clasts). Most, though not all, texts will make this distinction. Those that do will still use "erosion" as a catch-all term: that is, when you see a geologist saying that a rock has been "eroded" s/he does not mean to imply that it has not also been weathered.

Mechanical weathering is sometimes referred to as physical weathering. In both cases, the purpose of this nomenclature is to distinguish it from the processes collectively known as chemical weathering, in which chemical action breaks down the rocks. Chemical weathering will be covered in the next article.

Mechanical weathering involves mechanical processes that break up a rock: for example, ice freezing and expanding in cracks in the rock; tree roots growing in similar cracks; expansion and contraction of rock in areas with high daytime and low nighttime temperatures; cracking of rocks in forest fires, and so forth.

Mechanical weathering is probably the least important process we shall mention in this text, in that the history of the Earth and the resulting geological record would probably have been very similar if there was no such thing as mechanical weathering.

The main agents of mechanical erosion are: gravity; aeolian process (i.e. those caused by the wind); ice in the form of glaciers; and water in the form of rivers, waves, turbidity currents, and runoff caused by rainfall.

The reader will be familiar with most of the processes described, but we should provide a brief introduction to the concept of turbidity currents. A current of water that is turbid (that is, which contains a lot of sediment) is denser than clear water, and will flow along the bottom of a lake or the ocean, often over large distances and at high speeds, before failing and dispersing its load; such currents occur when a turbid river discharges into the clear waters of a lake, or they can be initiated by a mudslide on a continental shelf. A dust storm may be considered the aeolian equivalent of a turbidity current.

Abrasion of rocks is caused by the sediments carried by wind and water: waves, for example, can hurl their seaload of sand and shingle against a cliff; sandstorms can literally sand-blast rocks; the sand and silt carried by rivers or turbidity currents have the same effect.

Attrition is the effect these same forces have on the sediments themselves, breaking them into smaller fragments or rounding the clasts into smooth pebbles or rounded grains of sand. The efficiency of this process can be observed anywhere you can find beach glass, which originates as sharp-edged shards; the process of tumble-polishing semi-precious stones artificially emulates this process and will render most pebbles well-rounded in a matter of days.

The simple mechanical force of water or ice can break off chunks of rock, as when glaciers quarry rocks from the surfaces they move over, or when the pounding of waves hammers against a cliff.

Gravity can break off the overhang of a cliff undercut by abrasion and wave pounding, when the rock at the top of the cliff is unable to bear the mechanical strain. It is also instrumental in causing such things as rockslides and mudflows; such downhill motion is known collectively as mass wasting.

Erosional processes, as we have said, are defined by their ability to transport sediment as well as to create the clasts of which it is composed.

Currents of wind or water can transport sediments in three ways: in suspension, where light particles are carried along in the current above the ground, sea bed, or river bed; by saltation, where particles too heavy to be carried in suspension are bounced along the ground (or river-bed, or whatever); and creep, where particles are rolled along the ground. The size of the particles susceptible to these processes will depend, of course, on the velocity of the current.

By contrast, the size of the clasts that can be carried by glaciers is under no such limitation. One of the characteristic results of glacial action is the transport of huge boulders, up to the size of a house, known as erratic boulders. Gravity, too, is obviously under no such limitation; it is possible for entire layers of rock to slide down a hillside.

How do we know?

In this particular case, asking "how do we know?" seems almost superfluous, for the processes involved are neither hidden nor subtle. We can observe a sandstorm; we can see how the head of a waterfall shifts year on year, or how a river shifting its course scours out a new bed; we can see how cliffs crumble and the effects of landslides. The fact that glaciers carry boulders is evident, and the distance they travel each year can be measured; as can the quantity of sediment discharged at the mouth of a river.

A more interesting question is, how do we know that these processes have happened when the agency that caused them is no longer present? How, for example, do we identify the courses of glaciers long since melted, or of rivers that have dried up or shifted their beds? These are questions that we shall review in subsequent articles.

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Historical Geology/Mechanical weathering and erosion - Wikibooks, open books for an open world

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In this article we shall present a brief overview of erosion and mechanical weathering.It is possible to be brief because the erosional processes involved will be discussed at length in subsequent articles, so there is no need to do more than sketch out the topic in brief.

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1. Weathering can be caused by frost or crystal wedging
2. Two types of weathering called physical and chemical weathering
3. Erosion moves silt and fine grains of rock and sand far away and can form dunes.

Questions
What does physical weathering do to a rock?
How can water cause erosion?

Why I used this website: it has good information about both weathering and erosion and is easy to understand.

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Weathering and Erosion (U.S. National Park Service)

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1.I learned that wind erosion is found in higher elevation
2.Also learned that wind erosion made the entirety of the wave in arizona
3.The grand canyon was formed from the colorado river
:how long does it take for wind erosion to fully take place
2How the rock formations looked like before being eroded

why I clicked on it: The title picture intrigued me

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https://www.doe.virginia.gov/instruction/gifted_ed/project_promise/science_curriculum/grade_two/handouts/earth_science/weathering_erosion_pictures.pdf

1. There are different types of weathering, weathering may be caused by the action of
water, air, chemicals, plants, or animals, and there are different types of erosion

2.  Can something be weathered and eroded? What things have been naturally created from erosion and weathering?

3. I chose this because I thought it would give me a lot of information and it looked interesting.