Bellwork Using the Horton-Strahler technique (as demonstrated below), label the tributaries on your...
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Transcript of Bellwork Using the Horton-Strahler technique (as demonstrated below), label the tributaries on your...
Bellwork• Using the Horton-Strahler technique (as
demonstrated below), label the tributaries on your worksheet
The River’s Upper CourseLearning Objectives:• Recognise upper course
features from maps and photographs
• To be able to explain how features such as V-shaped valleys and waterfalls are formed.
• To understand how the processes of erosion and weathering form these features.
In your table groups write down answers to these questions on an upper course photograph
• How steep are the slopes?
• How wide is the channel?
• What is the bed load like?
• What are these?• Where has most of
the erosion happened here?
• How fast is the water moving?
Upper Course River Features Include…
• steep-sided V-shaped valleys, • interlocking spurs, • rapids, • Waterfalls• gorges.
• These are all features formed by EROSION!
Find someone who…
Can explain what a plunge pool is
Can name a famous Gorge
Has been down river rapids in a boat
Knows why we find waterfalls in the upper course of a river
Can tell you what causes the white water in rapids
Can explain the difference between vertical and horizontal erosion
Can name the process that breaks up big jagged boulders into smoother smaller pieces.
Best answers..? Take your completed card back to your table and highlight which ones are the best answers
Best answers..? Take your completed card back to your table and highlight which ones are the best answers
Can explain what a plunge pool is
Deep body of water directly beneath a waterfall
Can name a famous Gorge Cheddar Gorge (Uk), Grand Canyon
Has been down river rapids in a boat
Knows why we find waterfalls in the upper course of a river
Because we have steep drops and bands or hard/ soft rock
Can tell you what causes the white water in rapids
Water flowing over large boulders in the chanel
Can explain the difference between vertical and horizontal erosion
Vertical = downwards cuttingHorizontal = sideways cutting
Can name the process that breaks up big jagged boulders into smoother smaller pieces.
Attrition
Formation of Waterfalls and Gorges
Using the above sequence to help you, write a short paragraph to explain how waterfalls form.
Use the following words somewhere in your answer:Hard RockSoft RockUndercuttingPlunge poolErosion
V-shape valley formation Write these out in the correct order in which a V-shape valley is formed:
1. This vertical erosion deepens the valley, making the sides steeper and exposed.
2. As the small stream flows downhill steeply, the bedload will erode downwards and scrape away the bottom of the channel (vertical erosion)
3. Over time, weathering and gravity wear away the steep valley sides, forcing material into the stream, which it uses to cut the valley deeper.
4. A small stream will naturally follow small depressions in the landscape.
V-shape valley formation4. A small stream will naturally follow small depressions in the landscape.2.As the small stream flows downhill steeply, the bedload will erode downwards and scrape away the bottom of the channel (vertical erosion)1. This vertical erosion deepens the valley, making the sides steeper and exposed.3. Over time, weathering and gravity wear away the steep valley sides, forcing material into the stream, which it uses to cut the valley deeper.