The BGS Lexicon of Named Rock Units — Result Details
Lower Stromness Flagstone Formation
| Computer Code: | LSF | Preferred Map Code: | LSF |
|---|---|---|---|
| Status Code: | Pending Upgrade | ||
| Age range: | Eifelian Age (DI) — Eifelian Age (DI) | ||
| Lithological Description: | Laminated, carbonate-rich siltstones and shales with subordinate fine-grained, thinly bedded sandstones. | ||
| Definition of Lower Boundary: | Drawn at unconformity where flagstones overlie Yesnaby Sandstone Group or pre-Devonian basement. | ||
| Definition of Upper Boundary: | Drawn at confromable upward passage to the Sandwick Fish Bed, upward passage being from sandstone and shale into limestone. | ||
| Thickness: | c.250m | ||
| Geographical Limits: | Orkney Islands | ||
| Parent Unit: | Caithness Flagstone Group (CNFL) | ||
| Previous Name(s): | Caithness Flagstone Series [Obsolete Name and Code: Use LCF, LSF, UCF, USF]
(-4751)
Lower Stromness Flags [Obsolete Name and Code: Use LSF] (-2923) Lower Caithness Flagstone Group [Obsolete Name and Code: Use LCF, LSF] (-1642) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Type Area | Western Mainland, Orkney Islands. | ||
| Reference(s): | |||
| Mykura W, 1976 British Regional Geology: Orkney and Shetland (HMSO, Edinburgh).] | |||
| 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. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| S117 S117 S119 S119 S120 S121 S122 | |||