Sea Caves, Deltas, Or Moraines)

Vocabulary Power Pack • Science • Water Shapes the Earth

Name Date Instructions: Explain one way water shapes the Earth (canyons, sea caves, deltas, or moraines). Identify cause-and-effect relationships in the boxes below.

Cause and Effect

Water shapes the Earth by

Cause Effect

Focus Question How does water shape the Earth?

Get Started Look at this picture from space. It shows a lot of water on Earth. Water covers three-fourths of the Earth. There is water in oceans, lakes, and rivers. There is ice, or frozen water, in cold places. There is ice at the far north and far south of the Earth.

Water and ice shape the Earth. They make canyons and other landforms. They build new land like deltas. Water changes Earth’s land in different ways.

cause (noun) a person, event, or thing that Power makes something happen Words effect (noun) a change that happens as the Oceans, rivers, and ice help shape the land on Earth. result of an action; a consequence or impact

© Learning A–Z All rights reserved. Image: © UmbertoPantalone/iStock/Thinkstock www.readinga-z.com Vocabulary Power Pack • Science • Water Shapes the Earth Conclusion Canyons • Sea Caves • Deltas • Moraines

Focus Question How does water shape the Earth?

Wrap It Up Water is a powerful force. It shapes the land on Earth. Flowing water cuts canyons. Ocean waves change the shape of land. Water moves and deposits soil and rock. This forms new land such as deltas and moraines.

Scientists study how water changes land. This helps them to learn about the Earth’s history.

Today, water still erodes land. It still moves soil and rock. Water continues to change the land on Earth. ▲ Power Up! The area around this delta has rich soil and is used for farming. How does water shaping the Earth affect the people who live here?

Show What You Know Read the Wrap It Up section and Explain to a partner one example Write a paragraph analyzing think about what you have learned of how water has changed or is one way that water shapes land. from this Vocabulary Power Pack. changing land in your community. Use the Cause-and-Effect Graphic How does water shape land? Write Make a drawing or write notes to Organizer to help plan your writing. or draw three examples on a separate help with your explanation. Share your writing. piece of paper.

Water Shapes the Earth: Canyons A canyon is a deep valley with high, steep sides that is usually made by a river.

Water Digs Deep Large canyons are very old. Water creates canyons over many years. It flows over land. The water creates cracks in rock. The water erodes the rock and carries it away. Canyons begin to form. More rock erodes over time. A canyon can become very deep.

The Colorado River shaped the Grand Canyon (right) over six million years. The river cut through the layers of rock. It formed steep walls. The walls have many layers of rock.

Scientists study rock layers in canyons. The layers tell about the history of the Earth.

Four million people visit the Grand Canyon in Arizona each year. Canyons Vocabulary erode (verb) to slowly destroy something using Think About It natural forces such as water The layers of land in the Grand Canyon (above) formed flow (verb) to move over time. Why is the oldest layer of rock at the bottom steep (adjective) almost straight up and down of a canyon?

Canyons • Sea Caves • Deltas • Moraines

Water Shapes the Earth: Canyons

Power Links canyon Use the Water Digs Deep text on Card 1a and the pictures on this page to answer the questions below.

1. How is the rock different river from the top to the bottom of a canyon?

2. What do you think might happen to a canyon if the water stops flowing? Did You Know? Cotahuasi Canyon in the country of Peru is nearly twice as deep as the Grand Canyon.

wall layers crack

Canyons • Sea Caves • Deltas • Moraines

© Learning A–Z All rights reserved. Images: top: © rchphoto/iStock/Thinkstock; bottom left: © Niels Kliim/123RF; bottom right: © Kevin Palmer/Dreamstime.com www.readinga-z.com Vocabulary Power Pack • Science Card 2a

Water Shapes the Earth: Sea Caves A sea cave is a cave formed by waves.

Wonder Waves Sea caves begin as small holes in cliffs next to the ocean. Waves crash against the rock. The waves carry sand. The sand in the water erodes the rock. The sea caves become larger.

The force of waves can push water into a sea cave. The water comes out of holes in the top of the cave. These holes are called blowholes. The water can also make the tops of caves fall. This makes big holes called sinkholes. Caves change and the land near the water changes, too.

Sea Caves Vocabulary Over time, some sea caves can become more than a thousand feet long. crash (verb) to hit something hard erode (verb) to slowly destroy something using natural Think About It forces such as water Look at the picture (above). Over time, what will happen force (noun) strength or power to the land above the sea cave?

Canyons • Sea Caves • Deltas • Moraines

Water Shapes the Earth: Sea Caves

Power Links Use the Wonder Waves text on Card 2a and the pictures on this page to answer the questions below. cliff 1. How can the force of water change land? cave 2. Why might an area above a sea cave be unsafe?

Did You Know? Be careful! Sea caves may be dry sometimes and full of water at other times.

blowhole coast sinkhole wave

Canyons • Sea Caves • Deltas • Moraines Images: top: © AlexanderCher/iStock/Thinkstock; bottom left: © John Burcham/National Geographic Creative; © Learning A–Z All rights reserved. bottom center left: © Ippei Naoi/iStock/Thinkstock; bottom center right: © Kevin Ebi/Alamy; bottom right: © 2630ben/iStock/Thinkstock www.readinga-z.com Vocabulary Power Pack • Science Card 3a

Water Shapes the Earth: Deltas A delta is flat land formed by deposits of rock, sand, and soil at the mouth of a river.

New Land from Old Land A delta is a flat piece of land. A delta is at the mouth of a river. Sand and soil in rivers form a delta. The rivers carry the sand and soil. They flow toward the ocean. Then the water slows down. The sand and soil drop to the bottom of the river. This sediment makes the river break into small streams. The sediment creates islands. The streams deposit more sediment. The delta grows larger.

A delta’s flat land and streams form wetlands. Many birds, animals, and plants live in wetlands.

Deltas Vocabulary deposit (verb) to leave something on a surface These wetlands are part of the Mississippi delta near the Gulf of Mexico. mouth (noun) the part of a river where it meets the ocean Think About It sediment (noun) material such as sand, rock, or soil Look at the picture (above). Why does the land have that is left by water, wind, or ice in another place many different shapes and sizes?

Canyons • Sea Caves • Deltas • Moraines

Water Shapes the Earth: Deltas

Power Links ocean Use the New Land from Old Land text on Card 3a and the pictures on this page to answer the questions below. delta

1. Why can deltas have many shapes?

2. What can happen to a delta if something blocks or stops the water flowing in a river? river Did You Know? The green triangle is the Nile River delta in Egypt. Most of Egypt is desert, but the Nile River delta is one of the world’s best farming areas.

streams wetlands

islands

soil

Canyons • Sea Caves • Deltas • Moraines

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Water Shapes the Earth: Moraines A moraine is a pile of rocks and soil left by a glacier, or large sheet of ice.

What the Ice Left Behind Earth’s climate was very cold 20,000 years ago. Glaciers covered much of the land. Glaciers are sheets of ice. They moved across the land. Glaciers carried and pushed soil and rock.

Then, the Earth warmed. The glaciers melted. They deposited soil and rock into piles. These piles are called moraines. The soil in moraines is good for farming.

Some moraines are at the end of glaciers. These moraines can tell scientists how far a glacier moved.

Moraines Vocabulary climate (noun) the usual types of weather in a place Glaciers push dirt and rock into hills, like bulldozers. farming (noun) the job of growing plants or raising animals on a farm Think About It melt (verb) to change from a solid to a liquid Picture how a bulldozer moves over land. What happens because of heat along its path?

Canyons • Sea Caves • Deltas • Moraines

Water Shapes the Earth: Moraines

Power Links glacier Use the What the Ice Left Behind text on Card 4a and the pictures moraine on this page to answer the questions below.

1. Today, glaciers across Earth’s surface are melting faster than ever. What does this tell us about Earth’s climate? rock

2. What information can scientists learn from studying moraines? Did You Know? As glaciers melt, water flowing from the melting ice carries till, or sand and soil mixed together, away from the glacier.

soil glacier

ice

melted ice rocks

Canyons • Sea Caves • Deltas • Moraines

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Name Date

Canyons Quick Check

Part 1 Instructions: Read each definition. Draw a line to the matching word.

to slowly destroy something using 1 steep natural forces such as water

2 almost straight up and down flow

3 to move erode

Part 2 Instructions: Look at the pictures. Use the word bank to label the numbered parts of the pictures on the lines below.

wall crack layers river canyon

1 1 4

2 2

4 3 5

© Learning A–Z All rights reserved. Images: top left: © rchphoto/iStock/Thinkstock; bottom left: © Niels Kliim/123RF; bottom right: © Kevin Palmer/Dreamstime.com www.readinga-z.com Water Shapes the Earth Vocabulary Quiz Vocabulary Power Pack • Science

Name Date

Sea Caves Quick Check

Part 1 Instructions: Read each definition. Draw a line to the matching word.

1 strength or power erode

2 to hit something hard crash

to slowly destroy something using 3 force natural forces such as water

Part 2 Instructions: Look at the pictures. Use the word bank to label the numbered parts of the pictures on the lines below.

wave cave coast sinkhole blowhole cliff

4 1

2 2 1 5 3

4 3 5 6

Images: top left: © AlexanderCher/iStock/Thinkstock; bottom left: © John Burcham/National Geographic Creative; © Learning A–Z All rights reserved. top right: © Ippei Naoi/iStock/Thinkstock; center right: © Kevin Ebi/Alamy; bottom right: © 2630ben/iStock/Thinkstock www.readinga-z.com Water Shapes the Earth Vocabulary Quiz Vocabulary Power Pack • Science

Name Date

Deltas Quick Check

Part 1 Instructions: Read each definition. Draw a line to the matching word.

1 to leave something on a surface mouth

the part of the river where it meets 2 sediment the ocean

material such as sand, rock, or soil that 3 deposit falls to the bottom of water

Part 2 Instructions: Look at the pictures. Use the word bank to label the numbered parts of the pictures on the lines below.

wetlands islands streams delta river ocean soil

2 1 1 2

3 6 3 4 4 7 5

5 6

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Name Date

Moraines Quick Check

Part 1 Instructions: Read each definition. Draw a line to the matching word.

the job of growing plants or raising 1 climate animals on a farm

to change from a solid to a liquid 2 farming because of heat

3 the usual type of weather in a place melt

Part 2 Instructions: Look at the pictures. Use the word bank to label the numbered parts of the pictures on the lines below.

glacier ice rocks glacier soil melted ice moraine

1 1 2 2 4

3 5

5 3 6 6

7 7

Images: top left: © Spencer Sutton/Science Source; bottom left: © Marli Miller/Visuals Unlimited/Corbis; © Learning A–Z All rights reserved. top right: © David Carey/Dreamstime.com; bottom right: © Gilbert S. Grant/Science Source www.readinga-z.com Water Shapes the Earth Vocabulary Quiz Vocabulary Power Pack • Science

Quick Check Answer Key

Canyons Quick Check Sea Caves Quick Check Part I Part I 1. erode 1. force 2. steep 2. crash 3. flow 3. erode Part II Part II 1. canyon 1. cave 2. river 2. cliff 3. wall 3. blowhole 4. layers 4. coast 5. crack 5. sinkhole 6. wave

Deltas Quick Check Moraines Quick Check Part I Part I 1. deposit 1. farming 2. mouth 2. melt 3. sediment 3. climate Part II Part II 1. delta 1. glacier 2. ocean 2. moraine 3. river 3. soil 4. streams 4. ice 5. islands 5. melted ice 6. soil 6. glacier 7. wetlands 7. rocks

Focus Question How does water shape the Earth?

Get Started When you look at the planet Earth from space, you see a lot of water. Water covers three-fourths of Earth. It fills oceans, lakes, and rivers. Ice, frozen water, covers cold places such as high mountains and the polar regions.

Moving water and ice shape and change the Earth. They create canyons, caves, and other landforms. They move soil and rock and build new land such as deltas. Over time, water changes Earth’s land in different ways.

Focus Question How does water shape the Earth?

Wrap It Up Water is a powerful force that shapes the land on Earth. Flowing water carves deep canyons. Ocean waves erode land along coastlines. Water can move sand, soil, and rock for many miles. It can deposit the sediment to form new land like deltas and moraines.

Scientists study the effects of water on land to learn about Earth’s history and past climate. Water still erodes, moves,

and builds new land today. Earth will continue to change ▲ Power Up! in the future as it is shaped by water. The area around this delta has rich soil and is used for farming. How does water shaping the Earth affect the people who live here?

Water Shapes the Earth: Canyons A canyon is a deep valley with high, steep sides that is usually made by a river.

Water Digs Deep Canyons are some of the most famous landforms shaped by water. Canyons form when water flows over the land and erodes rock. The water carries pieces of it away. Cracks form in the surface of the land. Over time, deeper layers of rock erode. A channel, sometimes thousands of feet deep, is formed.

The sides of the Grand Canyon (right) show layers that water cut through. These rock layers form steep walls above the Colorado River. It took the river over six million years to erode the rock. Scientists study the oldest layers at the bottom of the canyon. They can learn what the Earth looked like millions of years ago.

Canyons Vocabulary Four million people visit the Grand Canyon in Arizona each year. erode (verb) to slowly destroy something using natural forces such as water Think About It landform (noun) a natural formation on Earth’s The layers of land in the Grand Canyon (above) formed surface, such as a canyon, mountain, or hill over time. Why is the oldest layer of rock at the bottom steep (adjective) almost straight up and down of the canyon?

Canyons • Sea Caves • Deltas • Moraines

Water Shapes the Earth: Canyons

Power Links canyon Use the Water Digs Deep text on Card 1a and the pictures on this page to answer the questions below.

1. How is the rock different river from the top to the bottom of a canyon?

2. What do you think might happen to a canyon if the water stops flowing? Did You Know? Cotahuasi Canyon in the country of Peru is nearly twice as deep as the Grand Canyon.

wall layers crack channel

Canyons • Sea Caves • Deltas • Moraines

Water Shapes the Earth: Sea Caves A sea cave is a cave formed by waves.

Wonder Waves A wall of rock along a coast looks strong, but waves are stronger. Waves crash against a cliff with great force. In the small space the force increases. The waves carry sand and it grinds away the softer rock. Sea caves begin as small holes. Over time, the waves make the caves larger.

Sometimes pressure from waves causes water to shoot out through holes in the roof of the caves. These holes are called blowholes. As more rock erodes, the tops of some caves fall. This creates sinkholes. As caves erode and fall, the shape of land along a coast changes, too.

Sea Caves Vocabulary Over time, some sea caves can become more than a thousand feet long. crash (verb) to hit something hard force (noun) strength or power Think About It pressure (noun) the power produced when Look at the picture (above). Over time, what will happen something pushes against something else to the land above the sea cave?

Canyons • Sea Caves • Deltas • Moraines

Water Shapes the Earth: Sea Caves

Power Links Use the Wonder Waves text on Card 2a and the pictures on this page to answer the questions below. cliff 1. How can the force of water change the land? cave 2. Why might an area above a sea cave be unsafe?

Did You Know? Be careful! Sea caves may be dry when the tide is low and fill with water when the tide is high.

blowhole coast sinkhole wave

Water Shapes the Earth: Deltas A delta is flat land formed by deposits of rock, sand, and soil at the mouth of a river.

New Land from Old Land Deltas are flat pieces of land at the mouths of rivers. They form when rivers carrying sand and soil slow down. This happens as rivers flow into a large body of water such as an ocean. The slowing river deposits the sand and soil, forming small streams and islands.

Deltas grow larger over time as more of this sediment is deposited. These flat areas of land are also called wetlands. These wetlands are home to a variety of birds, reptiles, and other animals. They are also home to many types of plants. Deltas also make good farmland for farmers and provide good fishing for fishermen.

Deltas Vocabulary These wetlands are part of the Mississippi delta near the Gulf of Mexico. deposit (verb) to leave something on a surface flow (verb) to move Think About It sediment (noun) material such as sand, rock, or soil Look at the picture (above). Why does the land have that is left by water, wind, or ice in another place many different shapes and sizes?

Canyons • Sea Caves • Deltas • Moraines

Water Shapes the Earth: Deltas

Power Links mouth ocean Use the New Land from Old Land text on Card 3a and the pictures on this page to answer the questions below. delta

1. Why can deltas have many shapes?

streams wetlands

islands

soil

Canyons • Sea Caves • Deltas • Moraines

Water Shapes the Earth: Moraines A moraine is a pile of rocks and soil left by a glacier, or large sheet of ice.

What the Ice Left Behind Earth’s climate was much colder 20,000 years ago. Great sheets of ice called glaciers flowed from the north and south polar regions. In the northern half of the Earth, they carved out the five Great Lakes in the United States and Canada. The glaciers moved soil and rock as they pushed south. Under the glaciers, the heavy ice ground rocks into soil.

Then, the Earth warmed and the glaciers began melting. The melting ice filled lakes and left behind moraines. A moraine is a large pile of till, or soil and rocks mixed together. This new land is good for farming. The moraines tell scientists where the glaciers stopped moving over land. Moraines Vocabulary carve (verb) to form or make something by cutting Glaciers push dirt and rock into hills, like bulldozers. into a surface climate (noun) the usual types of weather in a place Think About It grind (ground) (verb) to break something into small Picture how a bulldozer moves over land. What happens pieces by rubbing it against a rough surface along its path?

Canyons • Sea Caves • Deltas • Moraines

Water Shapes the Earth: Moraines

Power Links glacier Use the What the Ice Left Behind text on Card 4a and the pictures moraine on this page to answer the questions below.

1. Today, glaciers across Earth’s surface are melting faster than ever. What does this tell us about Earth’s climate? rock

2. What information can scientists learn from studying moraines? Did You Know? As glaciers melt, water flowing from the melting ice carries till, or sand and soil, away from the glacier.

soil glacier

ice till melted ice rocks

Canyons • Sea Caves • Deltas • Moraines

Name Date

Canyons Quick Check

Part 1 Instructions: Use the word bank to complete the sentences below.

erode landform steep

1 The walls of canyons are , almost straight up and down.

2 When rocks , they are gradually destroyed by natural forces.

3 Mountains are a type of found on the Earth’s surface.

Part 2 Instructions: Look at the pictures. Use the word bank to label the numbered parts of the pictures on the lines below.

channel crack canyon layers wall river

1 1 5

2 2

4 4 5 3 6

Name Date

Sea Caves Quick Check

Part 1 Instructions: Use the word bank to complete the sentences below.

crash force pressure

1 is the strength or power of something such as a wave.

2 The of waves against rocks causes the rocks to wear away.

3 Waves , or hit hard, against sea walls and can cause damage.

Part 2 Instructions: Look at the pictures. Use the word bank to label the numbered parts of the pictures on the lines below.

cave blowhole cliff wave coast sinkhole

4 1

2 2 1 5 3

4 3 5 6

Name Date

Deltas Quick Check

Part 1 Instructions: Use the word bank to complete the sentences below.

sediment deposit flow

1 Rivers sand and soil when they slow down.

2 Rivers toward the ocean, carrying sand and soil.

3 is sand, rock, or soil that is left by water.

Part 2 Instructions: Look at the pictures. Use the word bank to label the numbered parts of the pictures on the lines below.

ocean soil river mouth streams wetlands delta islands

1 4 1

2 2

3 7 3 4

5 5 8

6 6 7

Name Date

Moraines Quick Check

Part 1 Instructions: Use the word bank to complete the sentences below.

carved climate grind

1 Heavy ice can rock, breaking it into smaller pieces.

2 is the usual types of weather in a place.

3 Glaciers out the Great Lakes, cutting a deep hole in the land.

Part 2 Instructions: Look at the pictures. Use the word bank to label the numbered parts of the pictures on the lines below.

ice till melted ice glacier moraine soil rocks glacier

1 1 2 2 5

3 6 4

6 3 7 7

4 8 8

Quick Check Answer Key

Canyons Quick Check Sea Caves Quick Check Part I Part I 1. steep 1. Force 2. erode 2. pressure 3. landform 3. crash Part II Part II 1. canyon 1. cave 2. river 2. cliff 3. channel 3. blowhole 4. wall 4. coast 5. layers 5. sinkhole 6. crack 6. wave

Deltas Quick Check Moraines Quick Check Part I Part I 1. deposit 1. grind 2. flow 2. Climate 3. Sediment 3. carved Part II Part II 1. mouth 1. glacier 2. delta 2. moraine 3. river 3. soil 4. ocean 4. till 5. streams 5. ice 6. islands 6. melted ice 7. soil 7. glacier 8. wetlands 8. rocks

Focus Question How does water shape the Earth?

Get Started When you look at Earth from space, you see a lot of water. In its liquid state, water covers three-fourths of the Earth. Water fills oceans, lakes, and rivers. In its frozen state, ice covers the Arctic, Antarctic, and high mountains. The land on Earth reveals the effects of all this water. Water carves rock to form canyons, caves, and other landforms. It moves materials to build new landforms like deltas and moraines. Water has shaped the Earth for millions of years—and continues to shape its appearance today.

Focus Question How does water shape the Earth?

Wrap It Up Water is a powerful force that shapes the land on Earth. Flowing water carves deep canyons and ocean waves erode land along coastlines. Water can pick up and transport soil and rock for hundreds of miles. Then it deposits the sediment to form new land like deltas and moraines. Scientists study the effects of water on land to learn about Earth’s history and past climate. Today, water continues to erode, transport, and build new land. Earth will look different in the future as it is shaped by water. ▲ Power Up! The area around this delta has rich soil and is used for farming. How does water shaping the Earth affect the people who live here?

Water Shapes the Earth: Canyons A canyon is a deep valley with high, steep sides that is usually made by a river.

Water Digs Deep Canyons are some of the most well-known landforms shaped by water. They begin forming when water flowing over land erodes rock and carries it away. Faults form in the surface of the land. Over time, deeper layers of rock erode until a channel, sometimes thousands of feet deep, is formed. In the sides of the Grand Canyon (right), you can see the different layers of rock that water has cut through. These layers of rock form the steep walls above the Colorado River far below. It took the river over six million years to form the canyon. Scientists study the layers to see how the Earth has changed over time. Engineers build dams across canyons to create reservoirs and generate power.

Four million people visit the Grand Canyon in Arizona each year. Canyons Vocabulary erode (verb) to slowly destroy something using Think About It natural forces such as water The layers of land in the Grand Canyon (above) formed generate (verb) to produce something over time. Why is the oldest layer of rock at the bottom steep (adjective) almost straight up and down of the canyon?

Canyons • Sea Caves • Deltas • Moraines

Water Shapes the Earth: Canyons

Power Links canyon Use the Water Digs Deep text on Card 1a and the pictures on this page to answer the questions below.

1. How is the rock different river from the top to the bottom of a canyon?

2. What do you think might happen to a canyon if the water stopped flowing? Did You Know? Peru’s Cotahuasi Canyon is nearly twice as deep as the Grand Canyon in the United States.

layers fault reservoir channel

dam

Canyons • Sea Caves • Deltas • Moraines

© Learning A–Z All rights reserved. Images: top: © rchphoto/iStock/Thinkstock; bottom left: © Niels Kliim/123RF; bottom center right: © Kevin Palmer/Dreamstime.com; bottom right: © AdamRadosavljevic/iStock/Thinkstock www.readinga-z.com Vocabulary Power Pack • Science Card 2a

Water Shapes the Earth: Sea Caves A sea cave is a cave formed by waves.

Wonder Waves A wall of rock along a coast looks strong. But ocean waves are even stronger. Waves crash against cliffs with great force, carrying sand with them. The force causes sand in the water to grind away rock, like sandpaper. Sea caves begin as small holes in softer rock. Over time, wave erosion makes the caves become longer and deeper. Pressure from waves forcing water into a sea cave may cause water to shoot out through holes in the roof of the cave. These holes are called blowholes. This increases erosion until some caves become unstable and collapse, forming a sinkhole. Gradually, as sea caves collapse, the coastline is reshaped.

Sea Caves Vocabulary erosion (noun) the process by which earth is worn Over time, some sea caves can become more than a thousand feet long. away by natural forces pressure (noun) the power produced when something Think About It pushes against something else Look at the picture (above). Over time, what will happen unstable (adjective) likely to move or fall to the land above the sea cave?

Canyons • Sea Caves • Deltas • Moraines

Water Shapes the Earth: Sea Caves

Did You Know? Be careful! Sea caves may be dry when the tide is low and fill with water when the tide is high.

blowhole coast sinkhole wave

Water Shapes the Earth: Deltas A delta is flat land formed by deposits of rock, sand, and soil at the mouth of a river.

New Land from Old Land Deltas are flat pieces of land at the mouths of rivers. Deltas form when rivers carrying sand and soil slow down. This happens when they flow into a large body of water such as an ocean. When the speed of the water slows, the river deposits the sand and soil. Often this sediment causes the river to split into smaller channels that deposit more sediment. Over time, the sediment builds up creating small islands at the river’s mouth. The flat low-lying land and channels of slow-moving water on deltas form wetlands. Wetlands are home to wide varieties of birds, reptiles, and other animals, as well as plants. Deltas are sources of rich farmland and fishing for cities.

Canyons • Sea Caves • Deltas • Moraines

Water Shapes the Earth: Deltas

Power Links mouth ocean Use the New Land from Old Land text on Card 3a and the pictures on this page to answer the questions below. delta

1. Why can deltas have many shapes?

streams wetlands

islands

soil

Canyons • Sea Caves • Deltas • Moraines

Water Shapes the Earth: Moraines A moraine is a pile of rocks and soil left by a glacier, or large sheet of ice.

What the Ice Left Behind Earth has gone through cycles of warm and cold climates for millions of years. It was much colder 20,000 years ago during the Ice Age when glaciers flowed from the north and south polar regions. For example, glaciers carved out the five Great Lakes in the northern United States and Canada. Glaciers picked up and pushed dirt and rocks beneath the flowing ice. The heavy ice ground rocks into soil. Then, the Earth warmed and meltwater filled the lakes. As the glaciers melted, they left behind moraines: piles of till, or soil and different sized rocks. Terminal moraines mark the end of the glacier’s advance. Ground moraines form much of the rich farmland around the world.

Moraines Vocabulary carve (verb) to form or make something by cutting Glaciers push dirt and rock into hills, like bulldozers. into a surface climate (noun) the usual types of weather in a place Think About It cycle (noun) a set of events that happen again and Picture how a bulldozer moves over land. What happens again in the same order along its path?

Canyons • Sea Caves • Deltas • Moraines

Water Shapes the Earth: Moraines

Power Links glacier Use the What the Ice Left Behind text on Card 4a and the pictures moraine on this page to answer the questions below.

1. Today, glaciers across Earth’s surface are melting faster than ever. What does this tell us about Earth’s climate? rock

2. What information can scientists learn from studying moraines? Did You Know? As glaciers melt, they continue to flow. This moves till forward as if it is on a conveyor belt in a factory.

soil glacier

ice till melted ice rocks

Canyons • Sea Caves • Deltas • Moraines

Name Date

Canyons Quick Check

Part 1 Instructions: Write a sentence for each word in the word bank on the lines below. Your sentences should show your understanding of each word’s definition.

erode generate steep

Part 2 Instructions: Look at the pictures. Use the word bank to label the numbered parts of the pictures on the lines below. Then, write a description of one picture on a separate piece of paper.

dam river reservoir canyon channel layers fault

1 1 4

2 2 3 5 4

3 6 6

7 7

Images: top left: © rchphoto/iStock/Thinkstock; bottom left: © Niels Kliim/123RF; © Learning A–Z All rights reserved. center right: © Kevin Palmer/Dreamstime.com; bottom right: © AdamRadosavljevic/iStock/Thinkstock www.readinga-z.com Water Shapes the Earth Vocabulary Quiz Vocabulary Power Pack • Science

Name Date

Sea Caves Quick Check

Part 1 Instructions: Write a sentence for each word in the word bank on the lines below. Your sentences should show your understanding of each word’s definition.

erosion pressure unstable

Part 2 Instructions: Look at the pictures. Use the word bank to label the numbered parts of the pictures on the lines below. Then, write a description of one picture on a separate piece of paper.

wave cave coast sinkhole blowhole cliff

4 1

2 2 1 5 3

4 3 5 6

Name Date

Deltas Quick Check

Part 1 Instructions: Write a sentence for each word in the word bank on the lines below. Your sentences should show your understanding of each word’s definition.

deposit flow sediment

Part 2 Instructions: Look at the pictures. Use the word bank to label the numbered parts of the pictures on the lines below. Then, write a description of one picture on a separate piece of paper.

soil streams wetlands ocean river delta islands mouth

1 4 1

2 2

3 7 3 4

5 5 8

6 6 7

Name Date

Moraines Quick Check

Part 1 Instructions: Write a sentence for each word in the word bank on the lines below. Your sentences should show your understanding of each word’s definition.

carve climate cycle

Part 2 Instructions: Look at the pictures. Use the word bank to label the numbered parts of the pictures on the lines below. Then, write a description of one picture on a separate piece of paper.

ice till melted ice glacier soil rocks moraine glacier

1 1 2 2 5

3 6 4

6 3 7 7

4 8 8

Quick Check Answer Key

Canyons Quick Check Sea Caves Quick Check Part I Part I Answers will vary. Answers will vary. Part II Part II 1. canyon 1. cave 2. river 2. cliff 3. channel 3. blowhole 4. layers 4. coast 5. fault 5. sinkhole 6. reservoir 6. wave 7. dam

Deltas Quick Check Moraines Quick Check Part I Part I Answers will vary. Answers will vary. Part II Part II 1. mouth 1. glacier 2. delta 2. moraine 3. river 3. soil 4. ocean 4. till 5. streams 5. ice 6. islands 6. melted ice 7. soil 7. glacier 8. wetlands 8. rocks