The BGS Lexicon of Named Rock Units — Result Details
Lusa Limestone Member
| Computer Code: | LUSA | Preferred Map Code: | notEntered |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Hettangian Age (JH) — Hettangian Age (JH) | ||
| Lithological Description: | Alternating fossiliferous wackestones, packstones and micritic limestones with interbedded calcarenites. | ||
| Definition of Lower Boundary: | This formation marks the local base of the Jurassic on Skye and generally unconformably overlies Neoproterozoic ("Torridonian") strata. | ||
| Definition of Upper Boundary: | The unit is a member within the Breakish Formation and the upper boundary is marked by a transition from carbonate facies of the unit to overlying massive sandstone. | ||
| Thickness: | 25 to 30m | ||
| Geographical Limits: | Typically in the northern part of Skye, east of Breakish, but part of the Breakish Formation, which is found within the Sea of the Hebrides Basin. | ||
| Parent Unit: | Breakish Formation (BRKH) | ||
| Previous Name(s): | Broadford Beds (part) [Obsolete Name and Code: Use LUSA]
(-1053)
(Unnamed Limestone) [Obsolete Name and Code: Use LUSA] (-3543) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Type Section | ObLusa, Breakish, Isle of Skye. Beds 2 to 16 as shown on Fig.7 of Morton and Hudson (1995). Morton, N, and Hudson, J D. 1995. | ||
| Reference(s): | |||
| 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. | |||
| Hudson, J D, and Trewin, N H. 2002. Jurassic. 323-350 in The geology of Scotland. Trewin, N H (editor). (London: Geological Society of London.) | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| none recorded or not applicable | |||