160 likes | 585 Views
River Processes. Lesson 3 – page 3. Lesson Aims. To learn what is erosion: Abrasion Hydraulic action Attrition Solution To learn what is transportation: Traction Saltation Suspension Solution To learn what is deposition. Key Skill = Communication. Erosion.
E N D
River Processes Lesson 3 – page 3
Lesson Aims • To learn what is erosion: • Abrasion • Hydraulic action • Attrition • Solution • To learn what is transportation: • Traction • Saltation • Suspension • Solution • To learn what is deposition. • Key Skill = Communication
Erosion • Erosion is the wearing away of land and then the transportation of the worn away material.
Erosion • Abrasion: When material carried by the river rubs against its banks and bed. • Attrition: Rocks transported by the river collide, break up into smaller pieces and become smoother and more rounded. • Hydraulic action: The force of moving water. • Solution: When chemicals in water dissolves the rock.
Activity • What is erosion? • What are the 4 processes that make up river erosion?
Transportation • Is the movement of the material that has been eroded. This material is called the load.
Transportation • Bedload (along the streambed – sometimes called traction) • Saltation (by a series of hopping movements along the bed) • Suspended load (above the bed) • Solution (dissolved in the water).
Activity • What is transportation? • What are the 4 processes that make up river transportation?
Deposition • As the river loses energy it can no longer carry its load. The load settles to the river bed. The larger load settles first.
Activity • Explain why deposition happens in rivers.
Extension Activity • Try to devise a sketch or sketches to help illustrate the processes of erosion and transportation.