Waterfalls

Question 1

What processes cause a waterfall

Answer 1

Differential erosion- as the less resistant rock (limestone) is eroded faster causing a step in the river bed through the processes of hydraulic action and abrasion.
There is predominant vertical erosion due to the high above sea level (high gpe).

Question 2

How is a waterfall formed

Answer 2

Water flows over a band of more resistant rock (dolerite) overlaying a band of less resistant rock (limestone); the rock becomes undercut and further erosion results in the formation and undercutting of a plunge pool (extended by abrasion). The more resistant rock (dolerite) (once formed a ledge) collapses due to gravity).

Question 3

Diagram of waterfall

Answer 3

Look in folder

Question 4

Example of a waterfall

Answer 4

High force river tees England- drops 21 metres. It flows over whinstone and limestone. It is 350m above base level.

Question 5

What is a waterfall

Answer 5

A cascade of water falling from a height, formed when a river or stream flows over a steep rock face

Question 6

When is a gorge formed

Answer 6

When a waterfall retreats and forms a gorge ahead of it.

Question 7

How long is the gorge at the high force waterfall in the upper teesdale

Answer 7

500m