Erosion and Deposition UNIT 5 STANDARDS: STATE OBJECTIVES: NCES 2.1.1, 2.1.3, LESSON 2

Lesson 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 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 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 Water Factors influencing erosion by water Rushing water erosion video 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 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 Deposition 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, Africa

Coastal 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 all of the material eroded at the coast end up? NC Dredging Projects – Article 1 Article 1 – Article 2 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 Erosion What is a glacier? How do glaciers cause erosion? 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 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 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, & Humans 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.

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

Section 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?