UNIT 3 Earth Settles Down Name: ______________________Teacher Check _____________

Unit 3 Earth Science: The Earth Settles Down

What You Will Learn:

How wind, ice and water change the surface of British Columbia

Rock materials are broken into smaller pieces through physical, chemical and biological weathering

Weathering materials are moved from one place to another by wind, gravity, water, and ice.

This process of movement is called erosion

Rocks and weathered rock material can be transformed into new rocks

How rocks are changed and recycled

Why Earth Science is AMAZING:

How Do They Know That???What do you already know about the formation of the earth?

Why Earth Science is AMAZING:

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Pre-quiz check in Lesson Key Words HW

Check

Post-quiz check in

3.1 Soil Surface Activity Soil LAB #1: Soil HW: Layers of Horizons

SoilDeltaPlateausPlainsPH level

3.2 Weathering LAB #2: Weathering Weathering Mechanical Weathering Chemical Weathering LAB #3: Plants Effects HW: Weathering Inquiry

Chemical weatheringMechanical weathering

Mid Unit Review

3.3 Erosion Erosion Philosopher’s Cafe HW: Erosion Agents

DepositionHorizonsErosionFloodplainLandslideGlaciersMoraineCirqueHorn

3.4 Sand & Fossils Sand LAB #4: Minerals in Sand Types of fossils LAB #5: fossil cast Geological Time Scale HW: fossils time scale Let’s Recap

SandGrainFossilMoldImprintCastAmberIndex fossilSandbarSand spit

Unit Three Quiz

What do you want to know?

Follow up: who’s got the answers?

Is soil living or non-living

What is a rock fragment?

How does weather affect rocks?

What is erosion?

Are there different kinds of soil?

What can soil tell us about Earth’s history?

Can Scientists test dirt for historical records?

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3.1 Soil Builds Up

Surface Activity on EarthScientists have developed theories regarding the way the Earth was __________________. They have also developed models of the structure of our planet. These theories and models have been the result of indirect observations.

The Earth is a consistently _____________ sphere. Many of those changes occur right on the surface. These surface activities may be ________________. _____________, and often ______________ in laboratories. They can be understood as the result of __________________.

Earth has been changing for a very long time. Some of the changes are relatively _________ but most took a very long time. Scientists believe that some of the processes that have changed the

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earth in the past _______________________________; the same processes are at work changing our world now. The idea is known as the __________________ _____________.

_____________ is a very important process of surface change. Weathering can be defined as the breaking down of the ___________________ by actions of ____________, ____________, ______________, ______________ or ______________. Remember that the lithosphere is the solid part of the Earth. Weathering is a very _____________ process. It is also a _______________ process the affects all substances that are exposed to the atmosphere.

Quick Check:

1. What is the principle of uniformity: _________________________ ____________________________________________________

2. What is weathering: _____________________________________ ____________________________________________________

3. What is the lithosphere: _________________________________ ____________________________________________________

4. What is affected by weathering: ___________________________ ____________________________________________________

SoilSoil is a valuable _________________. All life on land depends on it. Plants are rooted in soil and obtain _______________ for growth. Animals eat plants that grow in soil or other animals that eat soil and plants.

Soil is a mixture of _________________ things, such as _______________, ____________ and

____________. It contains organic material that comes from ____________ plants and animals. It also holds ___________, both plants and animals.

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There are many different _________ of soil, and each one has a unique characteristic. The kinds of soil in an area helps determine how well crops grow there. Soil can be ________, ________ or ___________. Highly acidic or alkaline soil can harm many plants.

Soil CharacteristicsCharacteristic Description

Colour: depends on the amount of air, water, organic matter and elements in the soil.

Brown to Black: organic matter; humusPurple-black: manganese (element)Yellow to reddish: iron (element)White to gray: salt (element)

Texture: determines how well water drains from a soil. Sand promotes drainage better than clay.

Sandy: roughSilt: soft, flaky or flouryClay: smooth when dry and sticky when wet.

Structure: the arrangement of smaller particles (sand, silt and clay) to form larger pieces.

Granular: individual pieces clumped together in small round grains.Blocky: cling together in block shapes.Prismatic: form vertical pillars.Platy: thin sheets piled horizontally.

Chemical condition: PH level Neutral: at 7Acid: below 7Alkaline: above 7

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Driving Question: Where can you find soil samples on the school grounds?

LAB #1 Soil Inquiry

Question: Where can you find soil samples on the school grounds?

Materials:- Buckets - Trowels - pH strips - pH color key - Acidic solution (for example, vinegar) - Acidic solution (for example, ash)

1. Look at PH Scale below. Identify the following, acidic, neutral and alkaline, correctly on line.

2. The ideal PH level for soil: between 6 and 7. When pH is above 7, some nutrients (like phosphorus, nitrogen, and sulfur) are harder for the plants to utilize. When pH in the soil is below 6, some nutrient levels (like manganese) are higher and can become toxic to sensitive plants.

3. Watch demonstration of PH test kit: First dip a pH strip into a basic solution and then dip one into the acidic solution to illustrate the spectrum. 

4. Complete your hypothesis. Where do you think you will find samples of each type of soil?

5. Search on the school grounds for three soil samples. Try to find samples that you think will match each PH category: acidic, alkaline and neutral.

6. Bring soil samples back to the lab for testing. Use PH strips to test each soil sample. Be sure to let the PH strip sit in the soil for 2 min before analyzing sample.

7. Complete the questions for LAB

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Hypothesis: Acidic ___________________________________________Alkaline ___________________________________________Neutral ___________________________________________

Why did you choose these sites?

Method:

Results:

Acidic:Soil Test Site: ____________________ Sample #: _____

Alkaline:Soil Test Site: ____________________ Sample #: _____

NeutralSoil Test Site: ____________________ Sample #: _____

1. Dip pH strips in your soil solution and leave submerged for at least 2 seconds.

2. Compare your strips to the pH key to approximate the pH of your soil solution. Estimating to the nearest decimal, what is the pH? ______

3. Next, use the probe to measure the pH of your soil solution. According to this method, what is the pH? ______

4. Fill in your row in the following data table.5. Is this soil acidic, alkaline or neutral? Does this soil fall within the

ideal range for plant growth? If not, what should we do?

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Due Date: ___________Four Main Soil Layers

Soil comes from weathered rock fragments. It has taken thousands of years to form. Soil is a combination of rock,

mineral, particles and inorganic matter. It forms distinctive layers known as horizons. Mature soil has four layers, and each layer has its known special content of mineral, colour, and texture. The uppermost layer, loam, contains decaying leaves and animal remains needed to form the loose, rich topsoil just beneath it. Below the topsoil horizon lies the subsoil, which contains minerals washed down from the horizon line. Humus, clay and tiny soil particles are also in this layer. The fourth layer, regolith, holds mostly weathered rock pieces. Below these layers lies the bedrock.

Colour the layers of each horizon:

Quick Check1. Soil forms from layers called:

a. Plate boundariesb. Stalagmitesc. Horizons

d.Characteristics

2. This determines how well water drains from soil:a. Textureb. Colour

c. Structured. Chemical condition

3. Soil with a PH below 7 is called: a. Alkalineb. Salty

c. Neutrald. acidic

3.2 Weathering Breaks Down

________________

________________

________________

________________

________________

LAB #2

The surface of the Earth is changed by five agents: ice, wind, plants, animals and chemical changes.

Question: Can you classify images of weathering?

Materials:- Photographs- Poster paper- Markers

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WeatheringThe Crust of the earth is constantly changing. Movement in the earth’s crust as a result of plate boundaries colliding and grinding past one another creates mountains. __________________ changes the earth’s surface over time by _____________________ rocks into smaller pieces. Through the process of erosion, soil and rock by products are swept away and _____________________ in other places.

There are two types of weathering: ______________ and ______________. Chemical weathering causes changes in the ________________ makeup of rocks and makes them _______________. Chemical weathering in caves causes ____________ and _____________. Mechanical weathering is the ____________ of rocks into smaller pieces by physical forces, such as ___________, __________, __________ and freezing. Mechanical weathering can be seen when expanding ________ breaks a rock in smaller pieces.

LAB #2

The surface of the Earth is changed by five agents: ice, wind, plants, animals and chemical changes.

Question: Can you classify images of weathering?

Materials:- Photographs- Poster paper- Markers

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Which rock in this diagram is most resistant to weathering? How do you know?

Mechanical WeatheringMechanical weathering is the process of breaking down rock into smaller pieces. The makeup of the rock is _________________, only the _______. There are _________ different ways that mechanical weathering can occur.

________________ can produce mechanical weathering. During the day, the sun’s energy heats a rock’s surface. The internal temperature does not change. During the night, the rock’s surface will _________. The following day, the heating and cooling begin again. The repeated change from hot to cold may cause the rock to __________ or _________ layers that are parallel to the rock’s surface. This is known as _______________.

The second type of mechanical weathering is caused by __________, which may enter a small __________ or __________ in a rock. As temperature drops to freezing, the water will expand, causing larger cracks or holes to appear. When the water ________, it may move deeper into the crack until it refreezes. Eventually the rock will break into pieces. The repeated freezing and melting is known as

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_________________. This is a common problem for roads; ice wedging causes potholes and cracks.

The third type if known as _____________________. This may be the result of tree roots growing into the crack of a rock. As the tree grows and the roots expand, the rock breaks apart. This is known as _________________. Animals (such as worms, ants and woodchucks) may also burrow into soil, loosening rocks in the process. Finally, people are responsible for weathering due to digging, cutting out stone or building roads and bridges.

________________is the fourth type of mechanical weathering. ______________ move downhill due to the force of gravity. As the rocks ____________ down, they break and collide into smaller pieces.

The last type is known as ________________. This type of weathering is the _____________ away of solid particles by wind, water and other forces. Wind-blown sand is an abrasive that will weather even the hardest rocks.

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Chemical WeatheringWhile mechanical weathering alters only the size of the rock, chemical weathering alters the ______________ ________________, or the chemical makeup. There are ________ types of chemical weathering.

_________________ is the process combining ____________ with another substance. The end result is the creation of an entirely new substance. An example of oxidization is the combination of iron and oxygen to form ___________. If a material is coloured differently on the inside than the outside, it is an indication that oxidation may be taking place.

____________________ is a process in which carbon dioxide dissolves in water, forming carbonic acid. This _________ reacts with other substances, creating chemical change. An example is _____________, which dissolves some types of rocks. More evidence of this type of weathering is seen in the Mammoth cave and Carlsbad Canyon, both formed by this process when ____________ seeped underground.

The third form of chemical weathering is caused by acid plants, known as _____________________. Mosses and lichens are good examples. As the plants grow on the rocks, they produce acid that breaks down the minerals within the rock.

LAB #3 Effects of Plants on Rocks

Question: How do plants Effect Rocks?

Materials:- Plaster of Paris

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Hypothesis:__________________________________________________________________________________________________________________

Observation: What happened to the surface of the plaster? Why?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Conclusion: What effects do the plants have on rocks?

____________________________________________________________________________________________________________________________________________________________________________________________________________________________________

LAB #3 Effects of Plants on Rocks

Question: How do plants Effect Rocks?

Materials:- Plaster of Paris

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Due Date: ___________Weathering

1. Which type of weathering process do you think is the most interesting? Why? ________________________________________________________ _____________________________________________________________

2. Have you seen any evidence of this type of weathering before? Where? What did you see? ________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

3. What is mechanical weathering: ___________________________________ ______________________________________________________________

4. What is erosion: ________________________________________________ ______________________________________________________________

5. What is exfoliation: _____________________________________________ ______________________________________________________________

6. What is ice wedging:_____________________________________________ ______________________________________________________________

7. What is an example of mechanical weathering by gravity: _____________________________________________________________________________________________________________________________

8. How does chemical weathering differ from mechanical weathering: ______________________________________________________________ ______________________________________________________________

Inquiry Investigation: Weathering Experiments

Station #1: What is the Effect of cold temperature?

Materials: - baby food jar- plastic bag- permanent marker- ruler

Procedure:

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Results:

1. Which line was higher? Why? ___________________________________ ________________________________________________________________________________________________________________________

2. How do the results compare to water that freezes in the cracks of rocks? _____________________________________________________ ______________________________________________________________________________________________________________________________________________________

______________________________

Results:

Station #1: What is the Effect of cold temperature?

Materials: - baby food jar- plastic bag- permanent marker- ruler

Procedure:

Station #2: What is the effect of changing temperatures?

Materials: - Glass marbles- Heavy saucepan- Hot plate - Tongs- Oven mitt - Metal bowl- ice

* WEAR SAFETY GOGGLES!Procedure:

1. Place the marble in the saucepan.2. Add water until the pan is half full.3. Heat the water, with the marble, until it boils. 4. While the water is heating, put the ice in the metal bowl.5. Add tap water until the bowl is half full. 6. After the water in the pan has begun boiling, remove the marble

with tongs. 7. Immediately place the marble in the bowl of ice water. 8. Record the results.

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1. What effect did the change of temperature have on the marble? ________________________________________________________________________________________________________

2. How do your results compare to the effects of temperature change on rocks? ______________________________________________ ________________________________________________________________________________________________________

Results:

1. What happened to the sand and steel wool immediately: __________ ________________________________________________________________________________________________________

2. What happened to the sand and steel wool after 24 hours/ 48 hours/ 72 hours: ____________________________________________ ____________________________________________________________________________________________________________________________________________________________

3. What caused the changes? _______________________________ ____________________________________________________________________________________________________________________________________________________________

Station #3: What is the effect of oxidation?

Materials: - Steel wool- Dry, clean sand- Large tray

Procedure: 1. Place the sand in the tray.2. Place the steel wool in the tray.3. Wet the sand and the steel wool.4. Observe the sand and wool immediately. Record the results.5. Observe the sand and steel wool over the next 24 hours, 48

hours and 72 hours. Record the results.

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4. How is this similar to changes chased by nature: _______________ ____________________________________________________________________________________________________________________________________________________________

5.

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3.3 Erosion Takes you Places

Erosion and Deposition

The small pieces of rock broken down by weathering can be carried away by ___________. Erosion is the wearing away of the Earth’s surface by _______, _______, _______or _______. Erosion takes away the soil in one place and deposits in another place. When these materials are swept to a new location, it is called ______________. Over time, moving water created an eroded path, causing ______________ and ______________. Rain carries _____________ from the land to larger bodies of water. The sediments form rich ___________ the mouth of rivers before entering the ocean. Planting trees and grasses can help to ____________ and slow down the water, and this helps to ___________ erosion.

Most of the time, erosion is a ________________ process. It may take millions of years for agents of erosion to make noticeable changes to the Earth’s surface. The Grand Canyon in Arizona is the result of close to _______ million years of erosion.

Erosion, however, can also act very quickly. An unusually rainy period can cause rivers to overflow their banks and flood areas surrounding them. The erosion caused by rapid rivers have quick, devistating results for the earth’s surface and its inhabitants.

Write a definition for each of the following:

Weathering: _______________________________________________ _________________________________________________________Erosion: __________________________________________________ _________________________________________________________Deposition: _______________________________________________ _________________________________________________________

Philosopher’s CAFÉWHO IS THE MOST LETHAL AGENT OF EROSION?

Choose one of the following agents: - Agent H20 Runoff A

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- Agent H2) Runoff B- Agent H2O Rivers A- Agent H2O Rivers B- Agent H2O Rivers C- Agent Glaciers Poles and Mountains- Agent Glaciers Destroy - Agent Glaciers Create- Agent Waves Sea- Agent Waves Beaches, Bars and Splits- Agent Wind Deflation- Agent Wind Dune

Read your mission, familiarizing yourself with your territory, your task and the lethalness of your agent. Your job will be to bring as much information to the discussion as possible, and to try to convince others that you are the MOST lethal agent and

perfect for the task of mission EROSION.

Also provide

photographic evidence of your lethalness.

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Agent: H2OLethalness: ______%Mission: Runoff A

When water returns to Earth as precipitation, there are several things that can happen to the water. First, it may evaporate back into the atmosphere. Second, it may sink into the ground. Third, it may be used by plants and animals. Finally, it may become runoff.

Nearly 40% of all precipitation becomes runoff. It is the most powerful agent of change because the water carried particles with it, eroding the area. Even large, heavy particles may be dragged along. As they move, large pieces break down more particles as it is carried along.

The amount of runoff formed by precipitation depends on several factors. First, the amount of rainfall affects the runoff; during heavy rains there is greater runoff. Also, areas with higher annual precipitation will be affected more by runoff.

Another factor is the shape of the land. Very steep slopes will have greater runoff. The water will also be moving at a faster pace. Because of the greater speed, less water will be able to soak into the ground. Flat areas will be much less affected by runoff.

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Agent: H2OLethalness: ______%Mission: Runoff B

Nearly 40% of all precipitation becomes runoff. It is the most powerful agent of change because the water carried particles with it, eroding the area. Even large, heavy particles may be dragged along. As they move, large pieces break down more particles as it is carried along.

The type of surface water moves along is very important. Very porous surfaces will have less runoff because more of the water is absorbed. Impermeable surfaces, such as rock, do not allow much penetration, so they are more affected by runoff.

The amount of plant growth in the area is another factor. Plant roots are able to hold on to the soil. The roots also absorb some of the water. Areas with lush plant growth are less likely to have runoff. Bare ground, however, will show the result of runoff very quickly.

Finally, temperature affects the amount of runoff as well. When temperatures are warm, evaporation take the form of precipitation. When temperatures are cold, precipitation is trapped in snow and ice. When thawing occurs, there is runoff.

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Agent: H2OLethalness: ______%Mission: Rivers Old & Young

Rivers are important agents of erosion. They may be responsible for the greatest amount of erosion because they cover a high percentage of Earth’s surface.

Rivers form at higher elevations. Runoff, at the top of the mountain, will begin moving down the mountain using the areas of the surface that offer the least resistance. The runoff repeatedly uses the same path, eventually forming a channel. As the runoff continues to use the same channel, it deepens and the water moves faster. After a period of time, a stream is formed. Streams begin to flow together, forming rivers. The river continues to carry weathered materials, or sediment. The amount of sediment carried by a river is determined by velocity, the speed of the river and the amount of water it holds.

Scientists classify young rivers as immature. The characteristics of these rivers include steep-sided valleys that form a V. The water moves quickly, and rapids or waterfalls are not uncommon. Immature rivers experience a lot of erosion quickly. Large particles of sediment

move rapidly down the river.

Older rivers are classified as mature and have their own characteristics. They have an eroded valley floor, with sides of the valley often quite distant from the present riverbed. Mature rivers are often

curvy and they meander through the river valley. The water moves more slowly, carrying smaller particles of sediment. Erosion continues to be an active process, but at a much slower rate.

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Agent: H2OLethalness: ______%Mission: River’s Load

Rivers are important agents of erosion. They may be responsible for the greatest amount of erosion because they cover a high percentage of Earth’s surface.

The sediments carried by a river are referred to as the river load. The load consists of two parts: suspended load and bed load. The suspended load consists of the small particles of rock material that are dispersed throughout the water and easily carried downstream. The bed load consists of the larger particles that are dragged and bounded along the bottom.

A large fast-moving river will look quite muddy because it is carrying a heavy load. As a river slows, some of the materials settle out and the load becomes lighter, leaving the water looking clearer. Large particles tend to settle out directly on the riverbed. Smaller particles may settle where the river bends or curves. The force of the moving water will erode the outside section of a bend and deposit sediments on the slower, inside section of the bend.

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Agent: H2OLethalness: ______%Mission: River’s Formations

Rivers are important agents of erosion. They may be responsible for the greatest amount of erosion because they cover a high percentage of Earth’s surface.

As an aging river continues to meander, it may form an Oxbow lake. The process begins when the meandering river forms a U in the river. The action of the water continues to erode the outside of the two curves until the U forms a loop, leaving an island of land in the center to of the loop. Deposits begin to build up on either side of the island because the faster water is now bypassing the area. Eventually, these areas fill in completely and a lake will be formed, separated by the main line of the river.

Deposition by a river can also form a delta. When a moving river flows into standing water, such as a lake or ocean, it slows down rapidly. It is not longer able to carry all of the material on its load, so it deposits large amounts of

sediment. The sediment builds up to form a delta, often spreading out into the lake or ocean.

Rivers are also responsible for building up floodplains. When the water level in a mature river increases, it may overflow on both sides. When these floodwaters leave the river, they slow down and deposit large

amounts of sediment. These sediments build up to form rich, fertile soil that is often used for farming.

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Agent: GlacierLethalness: ______%Mission: Valley Glaciers

Historically, glaciers are important agents of erosion; however, they may not be the leaders in lethalness. They carry a more massive load than rivers do, but most cover only a small area and do their work over a short period of time.

What, exactly, are glaciers? They are large masses of moving ice and snow. They are found in areas where there is a great deal of snowfall that does not melt from winter to winter. Scientists have identified two basic types of glaciers: valley glacier and continental glaciers.

Valley glaciers form in mountains or high in old river valleys. Elevations are high enough and temperatures are low enough that snow, which falls during the winter and early spring, does not melt. It builds up from year to year and slowly turned to ice. Eventually, with the help of gravity, the weight of the ice begins to move the glacier down the mountain valley. Valley glaciers are also known as alpine glaciers.

There are three ways glaciers move earth’s materials. They push and carry debris in front of them like a snowplow. They pluck debris up from the land beneath them. It becomes frozen in the ice and moves under the glacier, scratching the surface of the Earth. Finally, glaciers loosen debris from the valley walls as they scrape through an area.

Agent: GlacierLethalness: ______%Mission: Continental Glaciers

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Historically, glaciers are important agents of erosion; however, they may not be the leaders in lethalness. They carry a more massive load than rivers do, but most cover only a small area and do their work over a short period of time.

What, exactly, are glaciers? They are large masses of moving ice and snow. They are found in areas where there is a great deal of snowfall that does not melt from winter to winter. Scientists have identified two basic types of glaciers: valley glacier and continental glaciers.

Continental glaciers form in the polar regions of the planet. They form large sheets of ice that may cover millions of square kilometers. Once again, snowfall does not melt, but accumulates. The weight of the piled snow pushes down on the glacier, moving it out from the center. Continental glaciers are sometimes referred to as ice caps and are commonly found in Greenland and Antarctica.

The Earth material carried by a glacier is known as the glacial load. It consists of both large and small particles of debris. Unlike a river load, the glacial load does not separate by size.

Agent: GlacierLethalness: ______%Mission: Destroy

As agents of erosion, glaciers wear down land surfaces. The debris that is frozen beneath the glacier serves as an abrasive. It grinds and polishes the surfaces that the glacier drags across.

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The erosive effect of a valley glacier is very similar to that of a river. Most noticeably, as an alpine glacier moves through an area, it erodes the V-shaped valley into a U-shaped valley, often leaving shear walls on either side.

Glaciers are also important agents of deposition. As the front end of the glacier moves into a warmer area, the ice begins to melt. The glacier continues to moves, but it melts faster than it moves. At this point, scientists say a glacier is retreating. As the ice melts, it drops its load. Rocks, clay, and other debris are deposited, often great distances from where they were originally formed.

All material deposited by a glacier is known as glacier drift. Drift, however, may be subdivided according to how it is deposited. If the drift is directly deposited by the glacier, it is called till. Till is not sorted by water action, so it is a mixture of sizes. If the drift is first carried away by water and then deposited, it is called outwash. Outwash is sorted by size and deposited in layers.

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Agent: GlacierLethalness: ______%Mission: Formations

Glaciers are responsible for forming several different types of landscape features. Moraines and ridges of till are deposited by glaciers. Terminal moraines form at the front edges of the glacier. Lateral moraines form along the sides. Studying the contents of the moraines helps scientist understand where the glacier form. The locations of moraines help them understand the extent of the glaciers movement.

Meltwater is formed when glacial ice melts. Meltwater may form a stream, carrying away sand and gravel from the glacier. The melt water stream may erode a channel and deposit outwash debris from in layers, similar to a rivers’ erosion and deposition. Meltwater may also form a sheet of water. This meltwater forms a fan-like area in front of a terminal moraine. The outwash is deposited across the area, forming a fertile plane. Many outwash plains are now used for farming.

Glaciers may also form lakes as deposits form in low areas, blocking rivers and trapping the water. This trapped water will form a lake covering much of the lowland area. Another type of lake is formed when blocks of ice are left behind as the glacier moves. The ice blocks become covered with debris and as they may they form a hole, known as a kettle lake.

Icebergs can also form from glaciers. These are most commonly found near Iceland and Greenland. As the iceberg

melts, debris may settle on the ocean floor.

Agent: WavesLethalness: ______%Mission: Shoreline

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Waves are curving swells of water caused by wind, tides, and even earthquakes. They move along the surface of water; another powerful agent of change. The size and strength of waves often depends on winds moving them. Strong winds will create major waves, while a lighter breeze will produce swells.

Waves shape the shoreline, which the body of water meets. The rate of erosion depends on several factors: the size of the wave is as important as the force of the wave. Weather conditions greatly affect the rate of erosion. Severe, stormy weather may increase the rate to as much as 25 meters per day. The type of rock or earth material along the shoreline is also an important factor. Loose, fragile soils will be eroded faster than large blocks of dense rock.

As waves move near the shoreline, their movements begin to slow down. Gravity pulls at the crests of the waves and they tumble over, forming a surf. This breaking action fragments the rock beneath. The water picks up rock material and carries it towards shore as suspended pieces of rock and debris. When the waves hit the shoreline, the particles fragment.

The action of waves also pushes water into cracks and holes along the shore. The abrasive action of particles causes these gaps to become larger.

Agent: WavesLethalness: ______%Mission: Beaches, bars and spits

Waves are responsible for eroding the shoreline. As this process takes place, several different features may form.

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When waves pound into cliffs, the bottoms of the cliff begin to wear away. As the base recedes, the top may break off and fall into the sea. There the action of the waves may grind the rocks into sand and silt. This is called a terrace, a flat platform at the base of a cliff. The terrace will slow down the action of the waves, slowing down erosion.

Some of the rocks along the cliff may be resistant to waves. They do not wear down and fall over. Instead, they form tall island called stacks.

Sometimes parts of sea cliff will have less resistance than the rest of the cliff. The waves form hollowed out areas, or a cave. If the waves are able to wear away the rock through the back of the cave, an arc may form.

When the waves erode the landforms, they move earth materials to other places. The deposition of these particles forms beaches. Finally, there may be soft sand, or there may be coarse gravel.

The colour of the beach may give us an indication of the types of materials from which it formed. Beaches along the Atlantic coast have white, sandy beaches formed from quartz. In Hawaii, black beaches have formed from weathered volcanic rock. Other beaches are made from shell or coral.

Most of the time, waves do not come straight at the shoreline, They come at an angle, forming longshore currents. The materials build up over a long time, forming sandbars. If a sandbar connects with the seashore, it is known as a spit.

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Agent: WavesLethalness: ______%Mission: Deflation

Wind is moving air. It does not appear to be an effective agent, but it creates incredible landforms.

Deflation is the process of removing loose material from the surface of the land. Wind is most effective in dry climates that do not have much vegetation to hold the soil and other matter in place. Eroded areas such as deserts, beaches and plowed fields are vulnerable to deflation.

The wind is able to pick up loose matter as it blows over an area. Most windblown matter is clay, silt, dust and sand. The finer particles travel several meters up above the ground. Other are bounced or rolled along the ground, causing abrasions and polishing rocks.

Since the larger particles remain close to the ground, this is where the most erosion takes place. The piles may end up meters high. The amount of damage done by wind depends on several factors. The size of the particles and the speed of the wind are very important. Smaller particles are less damaging and mild winds do not blow particles against other objects with force. The amount of resistance offered by the object is a final determining factor,

Several landscape features may be formed by wind. If the wind is able to go all the way through a cave, a wind

bridge or arch may form. Wind erosion takes a long period of time to erode.

Agent: WavesLethalness: ______%Mission: Dunes

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Wind is able to pick up particles and carry them a long ways. In order to stop this erosion agent, people have realized the need for barriers: fences, trees, shrubs, and plants are used to stop the effects of wind.

There are natural barriers as well along beaches, such as grasses, bushes and large rocks, which act as windbreaks. In the deserts, grass, rocks and trees serve the same purpose. The wind drops its load at the foot of windbreaks. Each time that is done, the deposit builds up more and more. Eventually, the deposits form dunes.

Sand dunes vary in size and shape. In general, however, the windward side develops a slope. The wind blows the crest, or top, of the dune. Once it reaches the top, wind dumps its load on the leeward side. The deposits form a steep bank, known as slipface.

Dunes are not fixed features. They move with the wind. The windward side continues to be eroded. The leeward side continues to build up. Dunes have been known to move and completely cover buildings.

An oasis is an interesting feature of the desert. To form an oasis, the area must be eroded to a depth where water is present. Water allows vegetation to grown. The vegetation prevents further erosion and expandsion.

Loess is a fertile soil created by wind deposition. Fine sand and silt from dry riverbeds and glacial lakebeds may not form dunes. Instead, it is carried farther away. The north and central portions of the Mississippi River Valley and Gobi

Desert have rich loess deposits.

Due Date: _____________Erosion Agents:Use the following terms: runoff, rivers, glaciers, wind, deflation, waves.

1. Which agent is in charge of eroding this territory? _____________

Evidence:

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2. Which agent is in charge of eroding this territory? _________________

Evidence:

3. Which agent is in charge of eroding this territory? _______________

Evidence:

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4. Which agent is in charge of eroding this territory? _______________

Evidence:

5. Which agent is in charge of eroding this territory? _______________

Evidence:

6. Which agent is in charge of eroding this territory?_______________

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Evidence:

SandSand consists of ___________ and _______________________ ranging in size from 0.06 to 2 millimeters in diameter. Sand may also contain large amounts of _______, _________, ___________, ___________ and ________. Most sand grains were once a part of solid rock. The rock breaks down and due to chemical or mechanical weathering, forms along rivers and beaches.

Sand creates coastal landforms, including ________, ___________, __________, and ___________. River sand originates from rocks and minerals carried from a river valley.

o Mounds of wind-blown sand are called ___________, formed when wind and waves transport materials onto the beach or desert.

o _________________ are long, narrow ridges built from an accumulation of sand along the outer part of the shore. They change constantly with wind and wave action.

o _________________ are a linear deposition of sand that forms a coastline. They connect the land and extend into the open water. Wind and water carry enough sand and gravel to create these narrow features.

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Observations:

LAB #4 Minerals found in Sand

Question: What is sand comprised of?

Materials:- Sand samples- Black paper- Tooth pick- Data chart- Microscope or hand lens.

1. Pour a sample of sand onto a black piece of paper. 2. With a toothpick, separate the grains. 3. Notice shapes, sizes and colours. Use a hand lens

or microscope to examine the sand. 4. Record your observation in the data table. 5. Repeat with different samples of sand.

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FossilsFossils provide clues to the past animals and plant life on Earth. They are the ________________, _____________ or __________ organisms leave behind. Fossils can be formed in several ways:

- Occasionally, entire organisms are preserve in some type of ______________. Insects are sometimes preserves in resins from trees, which eventually become amber.

- Giant woolly mammoths have been discovered in the tundra, buried in _____________.

- Fossils have been preserved in __________________________. The skeletal remains of living organisms are surrounded by sediment that settles on the bottom of a body of water, and remains in the sediment until it hardens into rock.

Fossils provide _________ to the types of plants and animals that were present many years ago. They also provide clues in determining the order in which layers of rock were formed. Since scientists know how old certain fossils are, they can date layers of rocks when they find fossils within them. Such fossils are called ___________________.

Other ways that fossils form:

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TAR (asphalt): In what is now downtown Los Angeles lies a 23 acre park called The La Brea Tar Pits, officially Hancock Park. Within the park are over 100 pits filled with sticky asphalt or tar. The tar pits were formed by crude oil seeping through fissures in the earth. The lighter elements of the oil evaporate leaving thick sticky asphalt. The pits are famous for the number and high quality of Pleistocene fossils that have been pulled from the pits. The fossils date between 10 and 40 thousand years old. Bones, teeth, shells, the exoskeletons of insects, and even some plant seeds have been pulled from the pits.

CARBONIZATION (distillation)- In this process of fossilization plant leaves, and some soft body parts of fish, reptiles, and marine invertebrates decompose leaving behind only the carbon. This carbon creates an impression in the rock outlining the fossil, sometimes with great detail.

PERMINERALIZATION: This is the most common method of fossil preservation. Minerals fill the cellular spaces and crystallize. The shape of the original plant or animal is preserved as rock. Sometimes the original material is dissolved away leaving the form and structure but none of the organic material remains.

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Name: ______________________ Fossil ______________________Name: ______________________ Fossil ______________________Name: ______________________ Fossil ______________________Name: ______________________ Fossil ______________________Name: ______________________ Fossil ______________________Name: ______________________ Fossil ______________________Name: ______________________ Fossil ______________________

LAB #5 Fossil Cast

Question: Can you create a fossil?

Materials:- Random objects bag- Plaster of Paris or clay- Petroleum jelly

1. Mix plaster of Paris to a consistency of pancake batter. 2. Pour a thick layer into a small shallow pan that has been

coated with petroleum jelly.3. Coat an object from the bag with jelly. 4. Lightly push into mold. Coat the entire surface with plaster so

that the object is covered. 5. When the mold is dry, gently split the mold in half. Remove the

object from the cast.6. Give your fossil to a friend and have them try to guess the

object that was in the cast. 7. Find as many friends as possible to share your fossil with.

Record your results below.

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Geologic Time Scale

Scientists have used fossils to make a time line of changes in the life on Earth. This scale is known as the Geologic time scale.

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Due Date: _________________Fossils and Old Stuff

1. Describe how fossils form: ________________________________________________________________________________________________________________________________________________________________________________________________________________

2. Why do very few organisms become fossils?____________________________________________________________________________________________________________________________________________________________

3. Would you expect to find fossils of dinosaur bones in rock that was 250 million years old? Why or why not?____________________________________________________________________________________________________________________________________________________________

4. What do you find the most fascinating about fossils?____________________________________________________________________________________________________________________________________________________________

5. Have you ever discovered a fossil? Where? What did it look like?____________________________________________________________________________________________________________________________________________________________

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To Recap:Earth’s major land formations (due to erosion and plate activity)

You can measure the quality of soil with PH tests Soil is made up of layers of horizons Rock materials are broken into smaller pieces by mechanical,

chemical and biological weathering Weathering materials are moved from one place to another by

gravity, wind, water and ice through a process called erosion There are 4 agents of weathering: wind, ice, water and waves Rocks and weathered materials can be transformed into new

rocks Fossils provide evidence of changes in life over time

Please return to page 3 and complete “Follow up: who’s got the answers?”

Earth Settles Down Word Bank

Scientific Terms Picture or Example Define in Your Own Words

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Amber

Cast

Chemical weathering

Cirque

Delta

Deposition

Erosion

Floodplain

Fossil

Glaciers

Grain

Horizons

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Horn

Imprint

Index fossil

Landslide

Mechanical weathering

Mold

Moraine

PH level

Plains

Plateaus

Sand

Sand spit

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Sandbar

Soil

Works Cited

Bailou, Brier et al. BC Science 10: Student Workbook. 2008. Vancouver: McGraw-Hill Ryerson

Bryson, Bill. A Really Short History of Nearly Everything. 2003. USA: Delacorte Press

Chapman, Anita et al. BC Science Probe 7. 2005. Toronto: Nelson

Logan, LaVerne. Geology: Rocks Minerals and the Earth. 2010. USA: Mark Twain Media

Mason, Adrienne, et al. BC Science 7. 2004. Toronto: McGraw-Hill Ryerson

Ward, Pat and Barbra. Geology: A Science Activity Book. 1994. USA: Mark Twain Media

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