Llandovery
The epoch of the Silurian interval (Silurian), approximately 443.1–432.9 Ma according to the ICS June 2026 chart.
Language and route: Welsh place-name. Welsh place-name → British geological English. Named after Llandovery (Llanymddyfri), Carmarthenshire, Wales.
Literal gloss: named for Llandovery
The name and its history
Murchisonian nineteenth-century regional usage; global standard 1984 · See attributed dates and cited original / standardisation works; first-use priority qualified where noted
- What does the word literally mean?
- Named for llandovery. Immediate scientific language-route: Welsh place-name → British geological English. This is a locality-based or geographical term, not a description of a universal geological event.
- What did the original author mean?
- A regional division of lower Silurian Welsh strata near Llandovery, later enlarged into an internationally correlated series.
- Why was the name needed?
- Mapped Welsh rock successions associated with Llandovery provided a recognisable lower Silurian reference division; successive surveys extended local rock names into time-correlation names.
- What evidence supported the original concept?
- Marine brachiopod and graptolite assemblages, stratigraphic superposition and later formal boundary sections supported broader correlation.
- How has geology changed the concept?
- The base of the Silurian and Llandovery is globally defined at Dob’s Linn in Scotland rather than the town supplying the name; local geography and global boundary must be kept distinct.
Further historical context
*Naming and context.* Mapped Welsh rock successions associated with Llandovery provided a recognisable lower Silurian reference division; successive surveys extended local rock names into time-correlation names.
*Evidence and later scope.* Marine brachiopod and graptolite assemblages, stratigraphic superposition and later formal boundary sections supported broader correlation. The base of the Silurian and Llandovery is globally defined at Dob’s Linn in Scotland rather than the town supplying the name; local geography and global boundary must be kept distinct.
Editorial qualification
The literal origin of the town name needs dedicated Welsh toponymic evidence; not inferred from its spelling.
Related names
Silurian · Wenlock · Ludlow · Pridoli · Rhuddanian · Aeronian · Telychian · Sheinwoodian · Homerian · Gorstian · Ludfordian · Graptolite · Stratigraphy · Superposition
Sources
- ICS International Chronostratigraphic Chart (June 2026) — Current formal unit, order, rank and numerical age
- Aldridge et al. (2000), British Silurian Stratigraphy, introduction — Historical British Silurian series and their relation to mapping
- Cocks, Toghill & Ziegler (1970), Stage Names within the Llandovery Series — Original four-stage proposal, later modified
- ICS international GSSPs: Silurian stages and boundary issues — Modern formal references, rank, locations and correlation