The BGS Lexicon of Named Rock Units — Result Details
Queensberry Formation
| Computer Code: | QBY | Preferred Map Code: | QBY |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Llandovery Epoch (SL) — Llandovery Epoch (SL) | ||
| Lithological Description: | Sandstone, typically medium- to coarse-grained but ranging from fine- to very coarse-grained, locally pebbly. Generally medium- to very thick-bedded or massive over thicknesses of tens of metres, units up to few metres thin-bedded. Interbedded siltstone or silty mudstone generally thin to medium beds but silstone units range up to several tens of metres locally. Rare conglomerate and intraclast-rich sandstone occur locally. Sandstone siltstone typically bluish grey when fresh, darker grey when weathered. Although of similar facies, the mid-Llandovery Queensberry Formation is younger then the adjacent early Llandovery Mindork Formation. Sandstone in both formations is predominantly quartzo-feldspathic, but is distinguished by accompanying volcanic debris; the Mindork Formation sandstone commonly contains sparse intermediate volcanic lithic debris and associated mafic crystal material (typically pyroxene); volcanic debris may be more common in the Queensberry Formation and tends to be more basic (spilitic) in character, mafic crystal material occurs locally but is relatively rare. | ||
| Definition of Lower Boundary: | Sedimentological boundary with rocks of the Moffat Shale Group. | ||
| Definition of Upper Boundary: | Faulted, no stratigraphical evidence preserved. | ||
| Thickness: | minimum 100m, may be substantially more. | ||
| Geographical Limits: | Southern Scotland. | ||
| Parent Unit: | Gala Group (GALA) | ||
| Previous Name(s): | Queensbury Grits [Obsolete Name and Code: Use ETRK, KKHP, QBY, SEO]
(-4034)
Queensbury (Buckholm) Grits [Obsolete Name and Code: Use QBY] (-476) Buckholm Grits [Obsolete Name and Code: Use QBY] (-3630) |
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| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Type Section | Quarry at Garpol Side, southwest of Moffat. | ||
| Reference Section | Blaebeck and hillside to north of Black Craig, north of Moffat. | ||
| Partial Type Section | Crags at Redgill Craig and Saddle Craigs (Black Hope, Moffatdale). | ||
| Partial Type Section | Incised stream section and crags - Hang Gill to Black Craig (Black Hope, Moffatdale). | ||
| 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. | |||
| British Geological Survey. 1991. Moffatdale. Solid Geology. 1:25 000. Classical areas of British geology. (Keyworth, Nottingham: British Geological Survey.) | |||
| Webb, B C, Rushton, A W A and White, D E. 1993. Moffatdale and the upper Ettrick valley. Description of the solid geology of parts of 1:25000 sheets NT10, 11, 20 and 21. Classical Areas of British Geology. (London: British Geological Survey, HMSO.) | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| none recorded or not applicable | |||