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Erosion is the movement of weathered rock.
Types of Erosion-
1. Mass Wasting - the downhill movements of weathered material due to gravity.
The angle of repose - steepest slope at which material will remain stable. As the slope of the material increases, the rate of mass wasting increases. Also determined by size, density, and shape of particles
Types of mass wasting-
Rockfall- large fragments of rock either fall from a cliff, or bounce down the side of a hill
Rockslides- occur on slopes that are less steep when rocks slide down the entire slope, rather than falling through the air
Slump- a process in which a mass of bedrock or soil slides down a slope in one large mass.
Mudflow- the rapid, downhill flow of a fluid mixture of rock, soil, and water. Mudflows generally occur when there are long periods of rainfall, and the water content of the soil builds up.
Soil Creep - a very, very slow form of mass wasting. It's just a slow adjustment of soil and rocks that is so hard to notice unless you can see the effects of the movement. These effects would be things like fence posts shifted out of alignment, or telephone poles tipping down slope.
2. Moving Water
All precipitation that is not absorbed by the ground is called runoff. Runoff can sometimes transport sediment, and often ends up in streams.
Streams
Streams - bodies of running water that flow under the influence of gravity. The running water cuts into the surface of the earth, building a channel. A bank on either side surrounds this channel.
Load - Material that is carried by the stream's water The faster a stream, the larger the load.
Different ways streams can carry their load
Traction - Large sediments are usually dragged or pushed.
Saltation - when particles bounce along the streambed.
Suspension - is the process of sediments picked up by the stream.
Solution When rocks are dissolved, they are said to be carried by this process.
Abrasion - Happens when the load of a stream is resistant rock - scratching can gouge rock - and a canyon can form. Ex. The Grand Canyon
Life Cycle of a Stream
Young Streams
When a stream is recently formed, it generally flows quickly. The stream wears a long v-shaped valley into the ground.
Mature Streams
In a mature stream, the slope gets eroded over time, and the slope becomes much less steep. The water flows more slowly and sediment accumulates at the bottom of the valley. Water flows around obstacles, rather than over them, and the stream's path forms curving loops called meanders. If the river overflows, the water slows down, deposits its load, and a broad flat floodplain is formed.
Old Age Streams
In an old stream, a large peneplain is formed. This is the area that used to be the floodplain, that had the stream meander though it. This peneplain has oxbow lakes and cutoffs.
http://www.bbc.co.uk/nature/humanplanetexplorer/environments/rivers#p009t2c2
http://www.classzone.com/books/earth_science/terc/content/visualizations/es1303/es1303page01.cfm?chapter_no=visualization
Ocean Erosion
The majority of the water in any stream will eventually end up in the earth's oceans.
The oceans’ agents of erosion are their waves. Result - sea cliffs, caves, stacks, and terraces may result. Also, Oceanic waves cause longshore drift, which can move sediments along the coast. This shapes the beaches of the world.
3. Wind Erosion
2 Types -
Deflation -the process of wind picking up sediment and transporting it.
Abrasion - the process in which wind blown sediments collide and wear rocks down.
4. Glaciers
What are Glaciers and how do they form?
Glaciers form after long periods of snowfall, usually in the mountains. After many meters of snowfall, the snow at the bottom begins to re-crystallize under the great pressure caused by the weight of the overlying snow. As the snow begins to crystallize into solid ice, the pressure continues to increase. This squeezing motion forces the ice to begin flow as a liquid.
Plucking - As glaciers move along, the bottom melts, and refreezes. As this occurs, the rocks and sediment lying under the glacier are picked up and frozen into the ice. Sediments the size of boulders can be plucked and carried thousands of miles.
Glacial scratches - Sometimes a plucked rock scrapes on the bedrock causing deep grooves as the glacier grinds slowly onward.
As the glacier begins to recede, or melt, it deposits these sediments.
Kettles - Large holes or depressions that are left when large rocks have been plucked by glaciers.
Till - The sediment left by a retreating glacier
Moraine - A large deposit of sediment that is pushed by a glacier, similar to a bulldozer, and is then deposited as the glacier recedes. Ex. Long Island.
http://www.on.ec.gc.ca/greatlakeskids/GreatLakesMovie5.html
The water cycle
The Water Cycle (also known as the hydrologic cycle) is the journey water takes as it circulates from the land to the sky and back again.
The sun’s energy is the driving force behind the water cycle. The sun heats up water on land and in the oceans, lakes, and seas. The water changes from liquid to vapor in a process called evaporation. The water vapor cools and in a process called condensation forms droplets in the atmosphere. These droplets become clouds. The droplets (or ice crystals if it’s cold enough) gather and then fall from the sky in a process called precipitation. This precipitation gathers in streams and rivers and flows and becomes run off, flowing back down to the oceans, seas, and lakes.
http://bogglesworldesl.com/watercycle_worksheets.htm
Are you drinking the same water a dinosaur drank?
Could you be drinking the same water a saber tooth tiger lapped up?
Water on earth moves in a continuous cycle. This is called THE WATER CYCLE. There is about the same amount of water on earth now that there was when the dinosaurs roamed our planet.
There are six important processes that make up the water cycle.
Evaporation - the process where a liquid, in this case water, changes from its liquid state to a gaseous state.
Condensation - the opposite of evaporation. Condensation occurs when a gas is changed into a liquid.
Infiltration - Infiltration is an important process where rain water soaks into the ground, through the soil and underlying rock layers.
Runoff - Much of the water that returns to Earth as precipitation runs off the surface of the land, and flows down hill into streams, rivers, ponds and lakes.
Precipitation - When the temperature and atmospheric pressure are right, the small droplets of water in clouds form larger droplets and precipitation occurs. The raindrops fall to Earth.
Transpiration - As plants absorb water from the soil, the water moves from the roots through the stems to the leaves. Once the water reaches the leaves, some of it evaporates from the leaves, adding to the amount of water vapor in the air. This process of evaporation through plant leaves is called transpiration
http://www.yvw.com.au/waterschool/juniors/water_comes.html#
Types of Erosion-
1. Mass Wasting - the downhill movements of weathered material due to gravity.
The angle of repose - steepest slope at which material will remain stable. As the slope of the material increases, the rate of mass wasting increases. Also determined by size, density, and shape of particles
Types of mass wasting-
Rockfall- large fragments of rock either fall from a cliff, or bounce down the side of a hill
Rockslides- occur on slopes that are less steep when rocks slide down the entire slope, rather than falling through the air
Slump- a process in which a mass of bedrock or soil slides down a slope in one large mass.
Mudflow- the rapid, downhill flow of a fluid mixture of rock, soil, and water. Mudflows generally occur when there are long periods of rainfall, and the water content of the soil builds up.
Soil Creep - a very, very slow form of mass wasting. It's just a slow adjustment of soil and rocks that is so hard to notice unless you can see the effects of the movement. These effects would be things like fence posts shifted out of alignment, or telephone poles tipping down slope.
2. Moving Water
All precipitation that is not absorbed by the ground is called runoff. Runoff can sometimes transport sediment, and often ends up in streams.
Streams
Streams - bodies of running water that flow under the influence of gravity. The running water cuts into the surface of the earth, building a channel. A bank on either side surrounds this channel.
Load - Material that is carried by the stream's water The faster a stream, the larger the load.
Different ways streams can carry their load
Traction - Large sediments are usually dragged or pushed.
Saltation - when particles bounce along the streambed.
Suspension - is the process of sediments picked up by the stream.
Solution When rocks are dissolved, they are said to be carried by this process.
Abrasion - Happens when the load of a stream is resistant rock - scratching can gouge rock - and a canyon can form. Ex. The Grand Canyon
Life Cycle of a Stream
Young Streams
When a stream is recently formed, it generally flows quickly. The stream wears a long v-shaped valley into the ground.
Mature Streams
In a mature stream, the slope gets eroded over time, and the slope becomes much less steep. The water flows more slowly and sediment accumulates at the bottom of the valley. Water flows around obstacles, rather than over them, and the stream's path forms curving loops called meanders. If the river overflows, the water slows down, deposits its load, and a broad flat floodplain is formed.
Old Age Streams
In an old stream, a large peneplain is formed. This is the area that used to be the floodplain, that had the stream meander though it. This peneplain has oxbow lakes and cutoffs.
http://www.bbc.co.uk/nature/humanplanetexplorer/environments/rivers#p009t2c2
http://www.classzone.com/books/earth_science/terc/content/visualizations/es1303/es1303page01.cfm?chapter_no=visualization
Ocean Erosion
The majority of the water in any stream will eventually end up in the earth's oceans.
The oceans’ agents of erosion are their waves. Result - sea cliffs, caves, stacks, and terraces may result. Also, Oceanic waves cause longshore drift, which can move sediments along the coast. This shapes the beaches of the world.
3. Wind Erosion
2 Types -
Deflation -the process of wind picking up sediment and transporting it.
Abrasion - the process in which wind blown sediments collide and wear rocks down.
4. Glaciers
What are Glaciers and how do they form?
Glaciers form after long periods of snowfall, usually in the mountains. After many meters of snowfall, the snow at the bottom begins to re-crystallize under the great pressure caused by the weight of the overlying snow. As the snow begins to crystallize into solid ice, the pressure continues to increase. This squeezing motion forces the ice to begin flow as a liquid.
Plucking - As glaciers move along, the bottom melts, and refreezes. As this occurs, the rocks and sediment lying under the glacier are picked up and frozen into the ice. Sediments the size of boulders can be plucked and carried thousands of miles.
Glacial scratches - Sometimes a plucked rock scrapes on the bedrock causing deep grooves as the glacier grinds slowly onward.
As the glacier begins to recede, or melt, it deposits these sediments.
Kettles - Large holes or depressions that are left when large rocks have been plucked by glaciers.
Till - The sediment left by a retreating glacier
Moraine - A large deposit of sediment that is pushed by a glacier, similar to a bulldozer, and is then deposited as the glacier recedes. Ex. Long Island.
http://www.on.ec.gc.ca/greatlakeskids/GreatLakesMovie5.html
The water cycle
The Water Cycle (also known as the hydrologic cycle) is the journey water takes as it circulates from the land to the sky and back again.
The sun’s energy is the driving force behind the water cycle. The sun heats up water on land and in the oceans, lakes, and seas. The water changes from liquid to vapor in a process called evaporation. The water vapor cools and in a process called condensation forms droplets in the atmosphere. These droplets become clouds. The droplets (or ice crystals if it’s cold enough) gather and then fall from the sky in a process called precipitation. This precipitation gathers in streams and rivers and flows and becomes run off, flowing back down to the oceans, seas, and lakes.
http://bogglesworldesl.com/watercycle_worksheets.htm
Are you drinking the same water a dinosaur drank?
Could you be drinking the same water a saber tooth tiger lapped up?
Water on earth moves in a continuous cycle. This is called THE WATER CYCLE. There is about the same amount of water on earth now that there was when the dinosaurs roamed our planet.
There are six important processes that make up the water cycle.
Evaporation - the process where a liquid, in this case water, changes from its liquid state to a gaseous state.
Condensation - the opposite of evaporation. Condensation occurs when a gas is changed into a liquid.
Infiltration - Infiltration is an important process where rain water soaks into the ground, through the soil and underlying rock layers.
Runoff - Much of the water that returns to Earth as precipitation runs off the surface of the land, and flows down hill into streams, rivers, ponds and lakes.
Precipitation - When the temperature and atmospheric pressure are right, the small droplets of water in clouds form larger droplets and precipitation occurs. The raindrops fall to Earth.
Transpiration - As plants absorb water from the soil, the water moves from the roots through the stems to the leaves. Once the water reaches the leaves, some of it evaporates from the leaves, adding to the amount of water vapor in the air. This process of evaporation through plant leaves is called transpiration
http://www.yvw.com.au/waterschool/juniors/water_comes.html#