The Weald- lowland landscape Flashcards
What does the Weald consist of?
undulating hills
What did the Weald use to be and what did this form?
A dome of folded rocks forming an arch called an anticline
What are encarpments?
higher areas of resistant rocks like chalks
what is a dipslope
behind the encarpment, gentle slopes follow the angle at which the rocks are tilted
What is a vale?
Softer clays from lower and flatter grounds
What kind of weathering occurs in the weald?
Chemical weathering as chalk is an alkali and is easily affected by acid rain
Biological weathering as trees and shrub roots break up rocks
Why is it unusual to find rivers in chalk areas?
Chalk is porous except when saturated after wet weather
Why are rivers common in vales?
As clay is impermeable
How do you get dry valleys where rivers once flowed/
During and after the last ice age water in chalk froze, making it impermeable, but then fresh water formed rivers and valleys
- the climate warmed up so water was able to seep through the chalk again
What is an anticline?
A ridge/fold of rock with many layers
