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Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29
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Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Apr 01, 2015

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Page 1: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Building Up Earth’s Surface

Unit C

Chapter 6 Lesson 3

C24 – C29

Page 2: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Objectives

• Recognize that constructive forces build up Earth’s surface features.

• Recognize deposition to be the dropping of sediments by water, wind, or ice.

• Understand that gravity is always the final process in sedimentation.

Page 3: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Main Idea

• Forces such as deposition and volcanic activity build up Earth’s surface features.

Page 4: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Review

• In the last lesson we discussed how the earth wears down.

• The process of weathering and erosion.

• Erosion carries away sediment, but what happens to it then?

• When it is dropped or released in a new area this is called deposition.

Page 5: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Deposition

• Deposition is a constructive force.

• This means it builds up the land.

• When the sediment is dropped in a new location, you are adding to the existing land there. You are building it up.

Page 6: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

River Systems

• Recall that the source of a river is usually inland at some high elevation.

• The water picks up sediment as it flows downward.

• At the mouth of the river the water empties into a lake or ocean.

• The mouth is level, causing the water to lose energy and drop the sediment.

Page 7: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Alluvial Fans

• Is a fan-shaped land mass that forms after a river rushes down a steep slope, then slows over a flat plain.

Page 8: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Delta

• A low plain that forms where a river enters an ocean.

• If the river is large, so is the delta.

• The Mississippi River has a large delta that extends out into the Gulf of Mexico.

Page 9: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Meanders

• As a river flows across a flat plain, its course begins to wind in curves called meanders.

• They increase in size as water erodes the outside of each curve and deposits sediment on the inside.

Page 10: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Flooding

• Flooding of rivers on lowlands deposits sediment.

• This sediment builds up the flood plain.

Page 11: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Why is sediment deposited as the slope of a river bed levels out?

• Because the sediment slows down and settles out.

Page 12: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

How are Earth’s surface features built up?

• Through forces such as deposition and volcanic activity.

Page 13: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

What is the difference between an alluvial fan and a delta?

• Both form when the flow of river water decreases quickly.

• An alluvial fan forms where a river flows down a steep slope onto a flat plain.

• A delta is a low plain, and forms where a river enters an ocean.

Page 14: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Pushing up Earth’s Surface

• Surface features can be pushed up from below.

• Below earth’s surface the temperature is so hot it melts rock.

• Melted rock below the Earth’s surface is called MAGMA

Page 15: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Magma

• Originates in a layer just below the crust.

• Pressure causes magma to push up Earth’s crust creating round, dome-shaped mountains.

Mount Olympus

Page 16: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Magma surfaces

• Magma can work its way through the crust.

• When it flows onto Earth’s surface it is called LAVA.

• As lava flows, it cools and hardens into rock.

Kilauea, Hawaii

Page 17: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Shield Cones

• Lava that has built up to form a huge deposit with gentle sloping sides.

• Often form on the ocean floor.

• The Hawaiian Islands are the tops of shield cones.

Page 18: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Hot Spots

• The Hawaiian Islands were formed due to a hot spot.

• As the Earth’s crust moves over the hot spot, new shield cones are formed.

Page 19: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Building Mountains

• The Himalaya Mountains in Central Asia were formed from a different constructive force than magma.

• As the Earth’s plates moved, they moved into each other.

• The pressure caused the crust to fold upward.

Page 20: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Himalaya Mountains

Page 21: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Remains

• The remains of living things can build up Earth’s surface.

• The chalk cliffs of Dover, England are made of shells of tiny sea animals.

• The shells eventually raise to the surface.

Page 22: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Coral Reefs

• Another type of formation produced from the remains of living things.

• In shallow tropical waters, tiny animals called corals gather in colonies.

• As they die, their skeletons build up into a bumpy ridge called a reef.

Page 23: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

What process created the Himalayas?

• They formed when huge sections of Earth’s crust pushed into each other.

Page 24: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

How are chalk cliffs and coral reefs alike? How are they

different?

• Both are formed from remains of living things. • Chalk cliffs are made of the shells of tiny sea

animals that were deposited on the sea floor millions of years ago, then raised to the surface.

• Coral reefs are the skeletons of tiny animals called corals that build up in tropical waters

Page 25: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Glacial Deposits

• As we learned in Social Studies thousands of years ago there were large glaciers over Asia, Europe, and North America.

• The ice chunks were forces of erosion.

• Huge amounts of soil & rock were pushed ahead of the ice and carried along in the glacier’s bottom layers.

Page 26: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Glaciers

• The ice melts• It had changed the

landscape.• Rock material

deposited by a glacier is called till.

• Till is dragged along the icy base.

Page 27: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Glacier Moraines

• Moraines are deposits of till at the front or snout of a glacier.

• Long Island, NY is the terminal moraine left when the last ice sheet melted.

Exit Glacier in Kenai Fjords National Park near Seward, Alaska 

Page 28: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Eskers

• Steams flowing through tunnels in melting glaciers deposit sand & gravel in ridges.

• These winding ridges are called eskers.

Page 29: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.
Page 30: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Small islands can form during the constructive process called?

• deposition

Page 31: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.

Landforms are found on the ______, which is Earth’s outer

rocky layer.

• crust

Page 32: Building Up Earth’s Surface Unit C Chapter 6 Lesson 3 C24 – C29.