Geoscience Reference
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evidence that movements of the Earth in this Region have been very limited compared
to those taking place in other regions. Most of the near-surface bedrock has therefore
avoided the deep burial within the Earth that causes rocks to harden, so it has remained
soft enough to be readily eroded by rivers, ice sheets and the sea. With this in mind,
it is perhaps not so surprising that East Anglia lacks high ground to such an unusual
degree.
The erosion of the East Anglian landscape has worked to create large areas of very
little topography at or close to present-day sea level, and ready to receive sediment
from the very recent (Flandrian) sea-level rise. These sediments have filled what few
hollows there were in an already flat landscape to produce areas of extreme flatness
such as the Fens and the Broads.
AREA 13: NORTHAMPTON TO CAMBRIDGE
In the general introduction to this chapter we saw how movements of the Earth's crust
in the East Anglian Region over the last 300 million years have been limited to very
gentle tilting (less than 1 degree across the Region as a whole). In terms of the present
scenery, this means that most of the natural features of Area 13 (Figs 228 and 229) are
predominantly due to surface processes (driven by rivers, ice, tides and storms) that
have progressively modified the landscape since these minor crustal movements took
place.
FIG
228.
Location map for Area 13.
