The BGS Lexicon of Named Rock Units — Result Details

Kirkhope Formation

Computer Code: KKHP Preferred Map Code: KHP
Status Code: Full
Age range: Llandovery Epoch (SL) — Llandovery Epoch (SL)
Lithological Description: Turbidite (wacke) sandstone with variable proportion of mudstone/siltstone. Sandstone typically fine- to medium-grained but ranging from very fine- to coarse-grained; generally medium- to very thick-bedded (commonly up to 2m) over thicknesses of tens of metres interspersed with units up to a few metres thick that are very thin- to thin-bedded; usually with interbedded mudstone in very thin to thin beds, but passes laterally into sections with little interbedded mudstone that include units, tens of metres in thickness, of coarse-grained, massive garnetiferous sandstone. Sandstone and siltstone are typically greenish grey when fresh, pale brown weathering. Distinguished from the Selcoth Formation (Ettrick Group) to the north by the variable proportion of mudstone and the occurrence of relatively thick-bedded to massive, locally coarse-grained garnetiferous sandstone. The Kirkhope Formation is younger than the Selcoth and Thornylee formations. Distinguished from the Glendearg Formation (Ettrick Group) to the south by the common occurrence of very thick massive units of coarse-grained garnetiferous sandstone, although partly overlapping in age range suggesting some lateral equivalence. The Kirkhope Formation is distinct from the Glenbearg Formation in Gbase Sr data, although this distinction is less evident in sandstone whole rock composition.
Definition of Lower Boundary: Faulted, none preserved.
Definition of Upper Boundary: Conformable sedimentary contact with rocks of the Moffat Shale Group.
Thickness: Uncertain, likely to be at least several hundred metres.
Geographical Limits: Southern Uplands, Scotland.
Parent Unit: Ettrick Group (ETRK)
Previous Name(s): Queensbury Formation (-4033)
Queensbury Grits (-4034)
Buckholm Formation (-237)
Hawick Group (HWK)
Alternative Name(s): Hawick Group Undivided
Stratotypes:
Reference Section  Craggy hillside exposure on Craig Hill and adjoining river sections in the bed of Ettrick Water from Brockhoperig to Broadgairhill and tributary streams to the south. Webb et al., 1993. 
Type Area  River cliff section at base of formation in the Ettrick Water east of Kirkhope passing northwards into craggy hillside exposure on Kirkhope Hill and Towerhill End, Ettrickbridge, Scottish Borders Region, Scotland. 
Reference(s):
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.) 
Kassi, A M and Weir, J A. 1993. Depositional and geotectonic history of the Gala area, eastern Southern Uplands, Scotland. Transactions of the Royal Society of Edinburgh: Earth Sciences, Vol.84, 161-173. 
British Geological Survey. 1991. Moffatdale. Solid Geology. 1:25 000. Classical areas of British geology. (Keyworth, Nottingham: British Geological Survey). 
White, D E, Barron, H F, Barnes, R P and Lintern, B C. 1991. Biostratigraphy of late Llandovery (Telychian) and Wenlock turbiditic sequences in the SW Southern Uplands, Scotland. Transactions of the Royal Society of Edinburgh: Earth Sciences, Vol.82, 297-322. 
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:
none recorded or not applicable