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

3.4.1 Solid Geology
Carboniferous Coal Measures
STUDY SETTING
The units present are the Upper and Middle Coal Measures comprising a cyclical sequence of
sandstone, mudstones, seat earths and occasional thin nodular limestone horizons. The Middle
Coal Measures contain the productive coal seams of the South Staffordshire Coalfield.
The Triassic Sandstone
The Triassic Sandstone forming the Birmingham Aquifer comprises a thick sequence of
sediments accumulated during subaerial deposition in a desert environment (Allen et al,
1997). The sediments are fluviatile in origin and derived from a major braided river system
with evidence of aeolian dunes merging laterally into the water-laid deposits. The deposits lie
unconformably on the Carboniferous Coal Measures and are succeeded by the conformable
Mercia Mudstones above. The sediments range from friable to cemented depending on the
degree of calcite cementation. The aquifer forms part of the Sherwood Sandstone Group, and
comprises three units.
Kidderminster Formation (lower)
Comprising interbedded sandstone, breccia and conglomerate, the formation is believed to
represent part of a major river system flowing northwards with wadi mouth fan type deposits.
The unit comprises red-brown, medium- to coarse-grained, cross-bedded pebbly quartz
sandstone and pebble conglomerate with sparse mudstone layers
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