The BGS Lexicon of Named Rock Units — Result Details

Scalpay Sandstone Formation

Computer Code: SCS Preferred Map Code: notEntered
Status Code: Full
Age range: Pliensbachian Age (JE) — Toarcian Age (JT)
Lithological Description: The Scalpay Sandstone Formation comprises siltstones and sandstone, in a gradually coarsening-upwards succession to massive fine-grained sandstone. Locally cross-bedded and bioturbated. Fossiliferous horizons of Pseudopecten and other bivalves exist. The top of the formation is characterised by thin beds, ferriginous material and of chamosite-rich oolidal ironstone.
Definition of Lower Boundary: Diachronous coarsening upwards from fissile mudstone of the Pabay Shale Formation (PABS) to sandstone of the Scalpay Sandstone Formation.
Definition of Upper Boundary: Abrupt lithological change from thin beds of sandstone and ironstone of the Scalpay Sandstone Formation to fissile mudstone of the Portree Shale Formation (PEE).
Thickness: 10 m exposed.
Geographical Limits: Sea of the Hebrides Basin.
Parent Unit: Lias Group (LI)
Previous Name(s): Scalpa Sandstone [Obsolete Name and Code: Use SCS] (-1169)
Scalpa Sandstone Formation [Obsolete Name and Code: Use SCS] (-1807)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Reference Section  South of Rudha na Leac [NG 5990 3794 to 6004 3788], Beinn na Leac, Isle of Raasay. 
Type Section  Rubha na Leac Peninsula, Isle of Raasay. Complete section (Morton and Hudson, 1995). 
Reference Section  South of Dun Liath ruins, near Elgol, Strathaird, Skye. Partial upper section (Morton and Hudson, 1995). 
Reference(s):
Emeleus, C H, and Bell, B R. 2005. British Regional Geology: the Palaeogene volcanic districts of Scotland (4th edition). (Nottingham: British Geological Survey.) 
Morton, N. 1999b. Middle Hettangian (Lower Jurassic) ammonites from the Isle of Raasay, Inner Hebrides, and correlation of the Hettangian - lowermost Sinemurian Breakish Formation in the Skye area, north-western Scotland. Scottish Journal of Geology, Vol.35, Part 2, 119-130. 
Morton, N and Hudson, J D, 1995. Field Guide to the Jurassic of the Isles of Raasay and Skye, Inner Hebrides, north-west Scotland. In: Taylor, P D (editor), Field Geology of the British Jurassic. Geological Society of London, 209-280. 
Fyfe, J A, Long, D, and Evans, D, 1993. United Kingdom offshore regional report: the geology of the Malin - Hebrides sea area (London: HMSO for the British Geological Survey.) 
Cox, B M, Page, K N, and Morton, N. 2002. The Middle Jurassic stratigraphy of Scotland. In British Middle Jurassic Stratigraphy. Cox, B M, and Sumbler, M G (editors). Geological Conservation Review Series, Vol. 26. (Peterborough: Joint Nature Conservation Committee/Chapman and Hall.) 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S071 S081 S044 S044 S080 S051 S052 S081