The BGS Lexicon of Named Rock Units — Result Details
Plymouth Limestone Formation
| Computer Code: | PYL | Preferred Map Code: | PyL |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Eifelian Age (DI) — Frasnian Age (DR) | ||
| Lithological Description: | Comprises irregular masses of fine-grained pale grey stromatoporoid boundstone that pass laterally and vertically into coarse-grained crinoidal packstone and grainstone with scattered stromatoporoids and corals. Erosive floatstone and rudstone beds of reworked and broken coral and stromatoporoid colonies are also present. Beds of fine-grained skeletal packstone interdigitate with normal facies. Red argillaceous calcite mudstone and breccia are found as fissure fill. | ||
| Definition of Lower Boundary: | Faulted out. | ||
| Definition of Upper Boundary: | Faulted out. | ||
| Thickness: | Not known. (This is a reef, which varies from 0 where not developed). | ||
| Geographical Limits: | Mapped within the city of Plymouth (Sheet 348). Extending eastwards onto the Ivybridge (349) sheet. Discontinuous reef type deposits. | ||
| Parent Unit: | Tamar Group (TAMA) | ||
| Previous Name(s): | Torquay And Plymouth Limestones [Obsolete Name And Code: Use TQL Or PYL]
(TPL)
Plymouth Limestone (-901) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Type Area | Cliff sections and numerous quarry faces around Plymouth Hoe, and between Devil's Point and Eastern King Point. Plymouth Hoe: SX 477 538. | ||
| Reference(s): | |||
| Ussher, W A E. 1907. The Geology of the country around Plymouth and Liskeard. Memoir of the Geological Survey of Great Britain, Sheet 348 (England and Wales). | |||
| Leveridge B E, Holder, M T, Goode, A J J, Scrivener R C, Jones N S and Merriman, R J. 2002. Geology of the Plymouth and south-east Cornwall area. Memoir of the British Geological Survey, Sheet 348 (England and Wales). | |||
| Taylor, P W, 1951. The Plymouth Limestone; and the Devonian tetracorals of the Plymouth Limestone. Transactions of the Royal Geological Society of Cornwall, Vol.18, 146-214. | |||
| Chandler, P and McCall, G J H, 1985. Stratigraphy and structure of the Plymouth-Plymstock area: a preliminary revision. Proceedings of the Ussher Society, Vol.6, 253-257. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| E348 E349 | |||