The north and south downs Flashcards
Chalk is formed from the fossils of dead. sea creatures. Where did the fossils come from ?
75 million years ago during the CRETACEOUS PERIOD, the UK was covered by warm tropical seas. This resulted in marine deposits that created the chalk
What happened 30 million years ago that created the north and south downs
Large Earth movements cause the compacted layers of sediment to be forced upwards creating a giant, chalk covered dome
How were the High and Low Wealds formed
Over many years, water eroded the chalk, revealing the older sandstone and clay beneath.
What did the north and south downs form from
From the remaining chalk at the edges of the dome
How were the north and south downs formed
When the dome experienced erosion, the softer rocks at the centre of the dome were removed and this left the two escarpments of the north and south downs.
What does the south downs escarpment consist of
It consists of a steep scarp slope and the dip slope where the slope is gentler
What can be found at the top of the escarpment
Gently rolling hills
What did the last ice age and the processes of weathering and erosion create
V-Shaped dry valleys
Hilltops and ridges
