The BGS Lexicon of Named Rock Units — Result Details
Roseland Breccia Formation
| Computer Code: | RDBR | Preferred Map Code: | RBr |
|---|---|---|---|
| Status Code: | Pending Upgrade | ||
| Age range: | Givetian Age (DV) — Frasnian Age (DR) | ||
| Lithological Description: | [Olistostrome] Grey slaty mudstone with framework and matrix breccias/conglomerates, interbedded sandstone, felsic and mafic tuffs/lavas and metamorphic rock breccias. Olistoliths of Ordovician quartzite, Silurian and early to mid Devonian limestone, sandstone, breccia, metamorphic and mafic/ultramafic igneous rocks. | ||
| Definition of Lower Boundary: | No details yet provided. | ||
| Definition of Upper Boundary: | Dodman Thrust. | ||
| Thickness: | To 1.5km | ||
| Geographical Limits: | Roseland and Meneage, south Cornwall. | ||
| Parent Unit: | Gramscatho Group (GRO) | ||
| Previous Name(s): | "Meneage Crush Zone" [Obsolete Name and Code: Use RDBR]
(-3634)
Grampound Grit [Obsolete Name And Code: Use TRSA Or GRAD] (GPG) Meneage Olistostrome [Obsolete Name: Use RDBR] (MENO) Roseland Volcanics [Obsolete Name And Code: Use RDBR] (RSV) Meneage Formation [Obsolete Name and Code: Use RDBR] (-486) Roseland and Meneage Breccias [Obsolete Name and Code: Use RDBR] (-1136) Veryan Series [Obsolete Name and Code: Use RDBR, PWER] (-1780) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Type Section | Gerrans Bay and Veryan Bay sections, south Cornwall. | ||
| Reference(s): | |||
| Holder, M T and Leveridge, B E, 1986. A model for the tectonic evolution of south Cornwall. Journal of the Geological Society, London, Vol.143, 125-134. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| E353 E354 | |||