The BGS Lexicon of Named Rock Units — Result Details
Upper Stromness Flagstone Formation
| Computer Code: | USF | Preferred Map Code: | USF |
|---|---|---|---|
| Status Code: | Pending Upgrade | ||
| Age range: | Eifelian Age (DI) — Givetian Age (DV) | ||
| Lithological Description: | Laminated carbonate-rich siltstones and shales with subordinate fine-grained thinly bedded sandstones. | ||
| Definition of Lower Boundary: | Drawn at the base of the Sandwick Fish Bed, where limestone rests conformably upon laminated siltstones and minor sandstones of the Lower Stromness Flagstone Formation. | ||
| Definition of Upper Boundary: | Drawn at the conformable upward passage from the flaggy siltstones of the Rousay Member to fluvial sandstone of the Lower Eday Sandstone Formation. | ||
| Thickness: | c.560m | ||
| Geographical Limits: | Orkney Islands | ||
| Parent Unit: | Caithness Flagstone Group (CNFL) | ||
| Previous Name(s): | Upper Stromness Flags
(-594)
Caithness Flagstone Series [Obsolete Name and Code: Use LCF, LSF, UCF, USF] (-4751) |
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| Alternative Name(s): | Upper Caithness Flagstones |
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| Stratotypes: | |||
| Type Area | Northern and western parts of the Mainland and island of Rousay, Orkney Islands. | ||
| Reference(s): | |||
| Fletcher, T P. 1996, A review of the lithostratigraphy of the Old Red Sandstone Supergroup in Scotland north of a line from Fort William to Aberdeen. BGS Technical Report WA/96/39R. | |||
| Mykura W, 1976 British Regional Geology: Orkney and Shetland (HMSO, Edinburgh).] | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| S117 S117 S119 S119 S120 S121 S122 | |||