Appleby Group

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Appleby Group
Stratigraphic range: Permian
Type Group
Sub-units Brockram
Underlies Cumbrian Coast Group and Roxby Formation
Overlies mid-Carboniferous unconformity
Thicknessvariable
Lithology
Primary sandstone
Other mudstone, breccia
Location
Regionnorthwest England
Type section
Named for Appleby-in-Westmorland

The Appleby Group is a lithostratigraphical term referring to the succession of Permian Period aeolian and fluviatile rock strata which occur in northwest England and beneath the Irish Sea in the United Kingdom. [1]

The Appleby Group unconformably overlies a variety of older rock strata (Carboniferous). It is succeeded (overlain) by the Cumbrian Coast Group [2] Its lowermost sub-unit is the Brockram, a breccia which sits unconformably on a range of older strata. [3]

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The geology of the Yorkshire Dales National Park in northern England largely consists of a sequence of sedimentary rocks of Ordovician to Permian age. The core area of the Yorkshire Dales is formed from a layer-cake of limestones, sandstones and mudstones laid down during the Carboniferous period. It is noted for its karst landscape which includes extensive areas of limestone pavement and large numbers of caves including Britain's longest cave network.

The Ingleton Group is a group of Ordovician turbiditic sandstones, siltstones, conglomerates found within inliers in the Craven district of North Yorkshire, England. The two inliers are exposed in the valley of the River Doe northeast of Ingleton and at Horton-in-Ribblesdale to the east. Of deep marine origin, these grey-green rocks are unconformably overlain by late Ordovician and Silurian strata. The sandstones are commercially exploited at Ingleton Quarry.

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References

  1. http://www.bgs.ac.uk/Lexicon/lexicon.cfm?pub=APY BGS Lexicon of named rock units: Appleby Gp
  2. British Geological Survey 1:625,000 scale geological map Bedrock geology: UK South (5th edn) BGS, Keyworth, Notts
  3. "BGS Lexicon of Named Rock Units". British Geological Survey. Retrieved 19 January 2019.