Zone | Valley form and
drift geology | Land use | Frequency of mapped
palaeochannels | Nature of palaeochannel record |
Upland (above Rugeley,
Staffordshire) Figure 7 | Very narrow valley (<1km) with narrow
sinuous channel; narrow alluvial
floodplain with no gravel terrace. | Floodplain
grassland | Very infrequent; none
above Weston, Staffordshire | Narrow moisture-mark
features within floodplain |
Upper Middle
(Rugeley to Nottingham) Figure 8 | Valley typically 13km wide, expanding to
around 6km at a number of major confluence zones. Sinuous/meandering channel. Dominated by
gravel terrace, particularly in confluence zones.
Ratio of gravel to alluvium c. 2:1 | Predominantly
arable, with significant floodplain grassland |
Many smaller palaeochannels
(3.2 channels/km²) | Cropmarks the largest group (5060%);
floodplain depressions significant (c. 30%) |
Lower Middle (Nottingham to Gainsborough) Figure 9 | Valley typically 25km wide with fewer major confluences; sinuous/meandering channel.
Dominated by alluvium, with significant gravel terrace; ratio of alluvium to gravel c. 2:1 | Arable; some floodplain grassland | Fewer, broader palaeochannels
(1.7 channels/km²) Cropmarks predominate (c. 70%); 1020%
floodplain depressions |
Perimarine (below Gainsborough) Figure 10 | Broad, sinuous channel with occasional meander. Very broad and deep alluvial spreads; no gravel terrace | Arable often to channel
margins | Very few channels (0.2 channels/km²) | Cropmarks and field
boundaries only |