The BGS Lexicon of Named Rock Units — Result Details
Glendouran Breccia Formation
Computer Code: | GDN | Preferred Map Code: | notEntered |
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Status Code: | Full | ||
Age range: | Cisuralian Epoch (PLC) — Cisuralian Epoch (PLC) | ||
Lithological Description: | Mainly poorly sorted breccio-conglomerates containing clasts mainly of greywacke sandstone and siltstone. Some pebbly and gravelly sandstone interbeds. | ||
Definition of Lower Boundary: | Unconformity at the base of the formation overlying the Ordovician Kirkcolm Formation in Holmhead Burn [NS 8820 2082]. | ||
Definition of Upper Boundary: | Faulted off and not exposed, but lies towards the northeast in this local basin. | ||
Thickness: | c.700m | ||
Geographical Limits: | Small outlier, c.2-4km southsouthwest of Crawfordjohn, south Lanarkshire. | ||
Parent Unit: | Appleby Group (APY) | ||
Previous Name(s): | Snar Water Permian Breccia [Obsolete Name and Code: Use GDN]
(-2821)
Snar Valley Breccia [Obsolete Name and Code: Use GDN] (-4672) |
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Alternative Name(s): | none recorded or not applicable | ||
Stratotypes: | |||
Partial Type Section | Section in Holmhead Burn from unconformity at its base to the uppermost beds exposed in this burn. | ||
Reference(s): | |||
Peach, B N and Horne, J. 1899. The Silurian Rocks of Britain, Volume 1. Scotland. Memoir of the Geological Survey of the United Kingdom. | |||
1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
S015 |