Cumbrian Coast Group

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Cumbrian Coast Group
Stratigraphic range: Permian
Type Group
Sub-unitsSt Bees Shale Formation, St Bees Evaporite Formation, Barrowmouth Mudstone Formation, Eden Shales Formation
Underlies Sherwood Sandstone Group
Overlies Appleby Group
Lithology
Primary siltstone
Other mudstone, anhydrite, sandstone
Location
Country England
Type section
Named forcoast of Cumbria

The Cumbrian Coast Group is a Permian lithostratigraphic group (a sequence of rock strata) which occurs in the western part of Cumbria in northern England.

Distribution and stratigraphy

The group outcrops near Whitehaven on the Cumbrian coast and beneath the Vale of Eden. It comprises the St Bees Evaporite and the overlying St Bees Shale Formation which are between 0 and 100m and 0 and 215m thick respectively. [1] The lower formation sits atop the mixed lithology breccia known as Brockram. [2] It is also found beneath the Irish Sea where the Barrowmouth Mudstone Formation is the equivalent of the St Bees Shale Formation. [3] The Group can achieve thicknesses in excess of 300m here.

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References

  1. British Geological Survey 1:50,000 scale map sheet (England and Wales series) no 28 Whitehaven)
  2. "BGS Lexicon of Named Rock Units - Result Details". Bgs.ac.uk. Retrieved 14 November 2018.
  3. "BGS Lexicon of Named Rock Units". Bgs.ac.uk. Retrieved 14 November 2018.