Ardvreck Group

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Ardvreck Group
Stratigraphic range: Lower Cambrian
Pipe rock, SE ridge, Maol Chean-dearg. - geograph.org.uk - 230021.jpg
Quartz arenite with skolithos burrows, the Pipe Rock of the upper Eriboll Formation, viewed on a bedding surface
Type Group
Sub-units Eriboll Formation, An-t-Sron Formation
Underlies Durness Group
Overlies Lewisian complex or Torridon Group
Thicknessup to 142 m
Lithology
Primaryquartzite, quartz arenite
Location
Region Hebridean Terrane
Country Scotland
Extent Northwest Highlands
Type section
Named for Ardvreck Castle

The Ardvreck Group is a stratigraphic group of early Cambrian age found in the Northwest Highlands of Scotland. It lies unconformably on gneisses of the Lewisian complex or sandstones of the Torridon Group. It consists of two formations, the basal quartzites and quartz arenites of the Eriboll Formation and the overlying dolomitic siltstones and sandstones and quartz arenites of the An-t-Sron Formation. It is overlain conformably by the Ghrudaidh Formation of the Durness Group. The Ardvreck Group was at one time known as the "Eriboll Group". [1]

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References

  1. British Geological Survey. "Ardvreck Group". BGS Lexicon of Named Rock Units. Retrieved 2018-03-09.