river erosion and transport

9
River Processes

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Page 1: River erosion and transport

River Processes

Page 2: River erosion and transport

Roles of a river

Rivers have energy that means they can do work. The work they do is

I) Erosion

Ii) Transportation

Iii) Deposition

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Types of river erosion

1. Corrosion/abrasion –the wearing away of the bed and bank by the load carried by a river.

2. Corrasion/solution – the removal of chemicals expecially calcium which causes rocks to dissolve.

3. Hydraulic action- the force of air and water on the sides of rivers and in cracks

4. Attrition- the wearing away of the load carried by a river to create smaller, rounder particles.

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River Transportation1. Saltation – process of river transport by which

small particles bounce along the bed.

2. Solution – process of river transport by which material is carried dissolved in the water.

3. Suspension – process of river transport by which material is carried along within the water.

4. Traction – process of river transport by which material is rolled along the bed.

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Deposition• Deposition – when a river loses energy and

drops some or all of the material it is carrying.

Conditions under which rivers deposit material.