The impact of urban groundwater upon surface water - eTheses ...

Wildmoor Sandstone Formation (middle)
STUDY SETTING
The Formation comprises finer-grained deposits of sandstone with fewer pebbles indicating a
gradual reduction in sediment load and transport capacity and including some aeolian
deposits. The unit consists of orange-red, fine-grained, micaceous soft sandstone with sparse
mudstone layers
Bromsgrove Sandstone Formation (upper)
This lies unconformably on the lower divisions and consists of a series of upward fining units
from sandstone to mudstone. The overlying junction with the Mercia Mudstone group is
typically gradational with an upward increase in mudstone and siltstone, and a decrease in
sandstone beds. The unit comprises red-brown medium to coarse grained, sub-angular arkosic
sandstone, pebbly in places and interbedded with mudstones layers.
Mercia Mudstone Group
The mudstones of Upper Triassic age were laid down on arid alluvial plains as mudflats and
ephemeral lakes, at times connected to the sea at other times drying out giving rise to halite
and gypsum deposits. The unit comprises red-brown mudstone, minor, dolomitic siltstone and
sandstone beds. Nodules of gypsum occur throughout the formation.
3.4.2 Superficial Drift Deposits
The unconsolidated superficial deposits of the region have a complex distribution reflecting
the glacial and post-glacial history of the Pleistocene and Recent time (Figure 3.7). The
glacial deposition from ice sheets and melt-water reflects at least three periods of ice advance
and retreat. However, correlating units across the area associated with these different phases is
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