The BGS Lexicon of Named Rock Units — Result Details

Observatory Sandstone Formation

Computer Code: OBG Preferred Map Code: notEntered
Status Code: Pending Upgrade
Age range: Early Devonian Epoch (DL) — Early Devonian Epoch (DL)
Lithological Description: Sandstone with thick beds of dolomitic siltstone and mudstone.
Definition of Lower Boundary: Drawn at base of siltstone and mudstone of the Furse Argillaceous Beds at the base of the Observatory Sandstone Formation, where they rest conformably on sandstone of the Ward Hill Sandstone Formation.
Definition of Upper Boundary: Drawn at the conformable upward passage from sandstone of the North Haven Beds (of the Observatory Sandstone Formation) into sandstones, pebbly sandstones and conglomerates of the Vaasetter Sandstone Formation.
Thickness: c.950m
Geographical Limits: Shetlands, Scotland.
Parent Unit: Fair Isle Group (FIL)
Previous Name(s): Observatory Group (-2962)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Fair Isle, Southern Shetland, Scotland. 
Reference(s):
Mykura W, 1976 British Regional Geology: Orkney and Shetland (HMSO, Edinburgh).] 
House, M R, Richardson, J B, Chaloner, W G, Allen, J R L, Holland, C H and Westoll, T S. 1977. A Correlation of Devonian rocks of the British Isles. Geological Society of London, Special Report No.8, Scottish Academic Press, Edinburgh. 
Mykura, W, 1970. The Old Red Sandstone sediments of Fair Isle, Shetland Islands, Bulletin of the Geological Survey of Great Britain, No.41. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S126