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The Craven Group is a lithostratigraphical term referring to the succession of mudstone and limestone rock strata which occur in certain parts of northern and central England and northeast Wales in the United Kingdom within the Chadian to Yeadonian sub-Stages of the Carboniferous Period. Other lithologies including sandstones, siltstones and chert occur within the group.[1] The Group is subdivided into numerous formations, some of which previously enjoyed group status. In stratigraphic order (uppermost/youngest at top), these are:

  • Bowland Shale Formation (mudstone and siltstone)
  • Pendleside Limestone Formation (interbedded limestone and mudstone, conglomerate)
  • Hodderense Limestone Formation
  • Hodder Mudstone Formation (limestone and mudstone)
Craven Group
Stratigraphic range: Chadian-Yeadonian sub-stages of Carboniferous period
TypeGroup
Sub-unitsHodder Mudstone, Hodderense Limestone, Pendleside Limestone, Bowland Shale formations
UnderliesMillstone Grit Group
OverliesBowland High Group, Clwyd Limestone Group
Thicknessup to 5000m
Lithology
Primarymudstone, limestone
Othersandstone, siltstone, chert
Location
Regionnorthern England, English Midlands and northeast Wales
Type section
Named forCraven district

The Craven Group unconformably overlies the Bowland High Group and elsewhere the Clwyd Limestone Group. It is succeeded (overlain) by the Millstone Grit Group[2]

References

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  1. ^ http://www.bgs.ac.uk/Lexicon/lexicon.cfm?pub=CRAV BGS Lexicon of named rock units: Craven Gp
  2. ^ British Geological Survey 1:625,000 scale geological map Bedrock geology: UK South (5th edn) BGS, Keyworth, Notts

See also

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Geology of Lancashire