Erosion and DepositionErosion and Deposition

UNIT 5

STANDARDS:

STATE OBJECTIVES: NCES 2.1.1, 2.1.3, 2.1.4

LESSON 2

Lesson ObjectivesLesson Objectives

In this lesson, you will learn about:– How erosion occurs – The impact of living and nonliving things on

the process of weathering and erosion– The relationship of gravity on all agents of

erosion– What can be done to “control” erosion

Erosion and DepositionErosion and Deposition

What is erosion?

What is deposition?

Erosion is the movement of soil of rock from one place to another.

Deposition is the depositing of the material being dropped off in another location.

Role of GravityRole of Gravity

What role does gravity play in the process of erosion?

Gravity is the number 1 force in erosion.

Gravity is the force that pulls things from an area of high to an area of low.

Gravity tends to pull all materials downhill.

Gravity causes glaciers to move downhill.

Gravity causes water to flow downstream.

Gravity is responsible for landslides and mudslides.

Erosion by Running WaterErosion by Running Water

Factors influencing erosion by water

Rushing water erosion video

The volume of the water flowing (how much water)

The speed the water is moving (how fast)

Consider a gentle rain vs. as heavy downpour.

Video SegmentVideo Segment

Watch the video and answer the following:

Kingscliff Beach Erosion Project– What is the major erosion agent shown?– What can be done to control erosion at

Kingscliff Beach?– What is the economic impact to the area if

nothing is done?

Coastal Erosion and Coastal Erosion and DepositionDeposition

Where do all rivers, streams, and waterways end up?

What happens to all of the sediment the water was carrying?

All water eventually ends up in the ocean or lakes.

The sediment is deposited as the water slows…mouth of rivers, or lakes generally get the sediment.

Nile Delta, AfricaNile Delta, Africa

Coastal Erosion in NCCoastal Erosion in NC

Coastal Erosion in NC costs an average of …

$ 30 million per year (2010).

Who pays?

Where does it all go?Where does it all go?

Where does all of the material eroded at the coast end up?

NC Dredging Projects– Article 1– Article 2

On the coastal shelf and in important inlets and waterways.

Read the articles and report out on the reasons why dredge and what costs are involved.

Glacial ErosionGlacial Erosion

What is a glacier?

How do glaciers cause erosion?

Large mass of ice accumulated over thousands of years that is in motion.

As a glacier moves, the sheer mass carry large rocks (trapped in the ice) as the gouge the underlying bedrock. The movement is like sandpaper moving over Styrofoam.

Benefits of Glacial ErosionBenefits of Glacial Erosion

Great Plains

Bering Sea Gold

The fertile soil was deposited as the glaciers retreated north during each Ice Age.

As the glaciers move down to the ocean they carry lots of sediment which is deposited in the bays of Alaska.

Wind ErosionWind Erosion

Why wind

Dust Bowl Video

In areas with low precipitation and high temperatures, wind is the main agent of erosion.

Watch the Dust Bowl video.

– Answer the 5 “W”s Who, what, when, where,

why? Long term health problems

Erosion by Plants, Animals, & Erosion by Plants, Animals, & HumansHumans

Role of Plants in Erosion

Role of Animals

Role of Man

Plants break down the rock and dislodge the soil. Speeds erosion.

As animals burrow, the soil is disturbed and may erode.

As man builds, the soil and natural barriers are disturbed and may speed in erosion.

DubaiDubai

Watch how this small fishing village is transformed by oil. No expense is spared as islands are created using dredging.

Dubai Palm Island

Section ReviewSection Review

What is the role of gravity in erosion?Describe the various agents of erosion.Why is coastal erosion important here in

NC?Synthesis… how erosion can be beneficial

to man.Evaluation…what can be done to slow the

erosion caused by man?