The BGS Lexicon of Named Rock Units — Result Details

Gala Unit 5

Computer Code: GAL5 Preferred Map Code: GALA5
Status Code: Full
Age range: Aeronian Age (SA) — Aeronian Age (SA)
Lithological Description: Graded beds that may include wacke sandstone, siltstone and mudstone in variable proportion, interpreted as turbidites.
Definition of Lower Boundary: Southern faulted boundary: The Hooies Fault (Rhins of Galloway), Garheugh Fault (Wigtown). Stratigraphical lower boundary with underlying Moffat Shale Group (of Ordovician to Silurian age up to magnus Biozone).
Definition of Upper Boundary: Northern faulted boundary: Gillespie Burn Fault.
Thickness: c. 900m of near vertical strata.
Geographical Limits: Mapped from Ardwell Bay on the Rhins of Galloway (Sheet 1/3) to Peebleshire (Sheet 24 E). Correlation with Central Belt turbidites of Llandovery age in the Ards Peninsula, Northern Ireland.
Parent Unit: Gala Group (GALA)
Previous Name(s): Queensberry Grits (-1552)
Gala Group (GALA)
Intermediate Greywacke Group (-3414)
Alternative Name(s): Garheugh Formation
Stratotypes:
Reference Section  Coastal section around Ardwell Bay, 6 km SW of Sandhead, Rhins of Galloway, Sheet 1/3. Stone, 1995. 
Reference Section  Coastal section at Garheugh Port, east shore of Luce Bay, Sheet 4W. Barnes, in prep. 
Reference(s):
Stone, P, 1995. Geology of the Rhins of Galloway district. Memoir of the British Geological Survey, Sheets 1 & 3 (Scotland). 
McMillan, A A. 2002. Geology of the New Galloway and Thornhill District. 2002. Memoir of the British Geological Survey. Sheets 9W and 9E (Scotland). 
Barnes, R P, Anderson, T B and McCurry, J A . 1987. Along-strike variation in the stratigraphical and structural profile of the Southern Uplands Central Belt in Galloway and Longford Down. Journal of the Geological Society, 144, 807 - 816. 
Peach, B N and Horne, J. 1899. The Silurian Rocks of Britain, Volume 1. Scotland. Memoir of the Geological Survey of the United Kingdom. 
Lapworth, C, 1871. On the Lower Silurian rocks in the neighbourhood of Galashiels. Transactions of the Edinburgh Geological Society, 2, 46 - 58. 
Walton, E K. 1955. Silurian greywackes in Peeblesshire. Proceedings of the Royal Society of Edinburgh, B65, 327-357. 
Barnes, R P, (in prep). The geology of the Kirkcowan, Wigtown and Whithorn districts. Memoir of the British Geological Survey, Sheets 4W, 4E and 2 (Scotland). 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S001 S003 S004 S004 S009 S009 S016 S024 S024 N29