Erosion and Deposition

1. Erosion and Deposition Chapter 3 Section 1

2. Standard • S 6.2 Topography is reshaped by the weathering of roc and soil and by the transportation and deposition of sediment.

3. Anticipatory Set • Gravity affecting materials • Small board on desk, roll marble down, observe what happens • Small board on desk, roll block down, observe what happens • Put sandpaper on board, roll marble down, observe what happens • Put sandpaper on board, roll block down observe what happens • How were they different?

4. Vocabulary • Erosion- process of natural forces such as water, wind, ice or gravity that weathers a rock and moves it from one place to another. • Sediment- small, solid particles from weathered rocks • Deposition-laying down sediment in new places • Gravity- a force that moves weathered rocks downhill • Mass movement- any one of the several processes that moves rocks downhill

5. Input • Mudslide is a good example of erosion • It carries soil and gravel downhill after a rain • Gravity, water, glaciers, waves and winds all cause erosion. • The material that is moved by erosion is called sediment. • Sediment: rock, soil, plants and animal remains

6. Input • Deposition- where the agents of erosion deposit or lay down sediment. • It changes the land form • This cycle has been occurring for thousands of years • Weathering, erosion, and deposition act together to wear down and build up Earth’s surface.

7. Mass Movement Input • If you were on the top of a hill, sitting on a bike, what is the name of the term that pushes you down the hill without pedaling? • Gravity • Gravity causes mass movement • Different types of mass movement • Landslides • Mudflows • Slum • Creep

8. Input • Landslide- occurs when rock and soil slide rapidly down a steep slope. • They occur where road builders have cut highways through highways and mountains. • Mudflows- a rapid downhill movement of a mixtures of water, soil, and rock. The amount of water in a mudflow is higher than a landslide. • An earthquake can trigger mudflows and landslides

9. Landslide/Mudflow

10. Input • Slump- a mass of rock and soil rapidly slips down a slope. • It moves down in 1 large mass • Occurs when water soaks the bottom of soil that is rich in clay • Creep- very SLOW downhill movement of rock and soil. Result from freezing and thawing of water in cracks under the soil. • Creep may tilt objects at spooky angles.

11. Creep

12. Checking for Understanding • What is sediment? • What are the four types of mass movement? • What is mass movement caused by? • What is the difference between a slump and a landslide?

13. Guided PracticeIndependent Practice • Page 55 • # 1-4 • Check with teacher for answers • IP- • Note Taking Guide Pg 56-57 • # 1-21