Geoscience Reference
In-Depth Information
FIG
167.
Natural and man-made features of Area 9.
The general introduction to this chapter provides an overview of the bedrock geo-
logy of the Severn Valley Region as a whole. It also includes a generalised succession
for the bedrock layers below the surface blanket (Fig. 151). Although, like the rest of
Southern England, this Area has much bedrock of Jurassic and Cretaceous age, it also
includes older layers more typically seen further north and west. In terms of the bed-
rock near the surface, this Area is on the border between the newer and older bedrock
regions of Britain.
For the more detailed discussion of the influence of the bedrock on the scenery the
Area can be divided into four Landscapes, labelled
A
to
D
on Figure 168. I have sim-
plified the bedrock succession, representing it as a succession of layers of rock ranging
in thickness between a few metres to over a kilometre. Each of the layers was formed
over a period of time in the distant past when totally different landscape patterns pre-
vailed in the Area. Each consists of sedimentary rock (most commonly mudstone) that
was deposited in the sea or by rivers over a period of millions of years. The layers are
distinguished from the older and younger layers below and above them by the types of
rocks present, their arrangement and, in most cases, by characteristic fossils.
