The Stephanian is a

stage Stage or stages may refer to: Acting * Stage (theatre), a space for the performance of theatrical productions * Theatre, a branch of the performing arts, often referred to as "the stage" * ''The Stage'', a weekly British theatre newspaper * St ...

in the regional

stratigraphy Stratigraphy is a branch of geology concerned with the study of rock layers ( strata) and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks. Stratigraphy has three related subfields: lithostrat ...

of northwest Europe with an age between roughly 304 and 299 Ma (million years ago). It is a subdivision of the

Carboniferous The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carboniferous ...

system A system is a group of interacting or interrelated elements that act according to a set of rules to form a unified whole. A system, surrounded and influenced by its environment, is described by its boundaries, structure and purpose and express ...

period Period may refer to: Common uses * Era, a length or span of time * Full stop (or period), a punctuation mark Arts, entertainment, and media * Period (music), a concept in musical composition * Periodic sentence (or rhetorical period), a concept ...

and the regional Silesian

series Series may refer to: People with the name * Caroline Series (born 1951), English mathematician, daughter of George Series * George Series (1920–1995), English physicist Arts, entertainment, and media Music * Series, the ordered sets used in ...

. The uppermost units of the

Coal Measures In lithostratigraphy, the coal measures are the coal-bearing part of the Upper Carboniferous System. In the United Kingdom, the Coal Measures Group consists of the Upper Coal Measures Formation, the Middle Coal Measures Formation and the Lower Coa ...

of England and

Wales Wales ( cy, Cymru ) is a country that is part of the United Kingdom. It is bordered by England to the east, the Irish Sea to the north and west, the Celtic Sea to the south west and the Bristol Channel to the south. It had a population in 2 ...

are probably of Stephanian age, though the larger part of this formation is referred to the earlier Westphalian. The stage derives its name from the city of

Saint-Étienne Saint-Étienne (; frp, Sant-Etiève; oc, Sant Estève, ) is a city and the prefecture of the Loire department in eastern-central France, in the Massif Central, southwest of Lyon in the Auvergne-Rhône-Alpes region. Saint-Étienne is the th ...

for its coal mining basin in eastern central France (which itself derives from associations with

Saint Stephen Stephen ( grc-gre, Στέφανος ''Stéphanos'', meaning "wreath, crown" and by extension "reward, honor, renown, fame", often given as a title rather than as a name; c. 5 – c. 34 AD) is traditionally venerated as the protomartyr or first ...

) where strata of this age occur. In the official

geologic timescale The geologic time scale, or geological time scale, (GTS) is a representation of time based on the rock record of Earth. It is a system of chronological dating that uses chronostratigraphy (the process of relating strata to time) and geochro ...

of the ICS, the Stephanian is placed within the Pennsylvanian epoch (318-299 Ma).F M Gradstein, J G Ogg, A G Smith et al 2004, ‘A Geologic Time Scale 2004’. The (regionally defined) Stephanian stage corresponds to the (internationally used)

Gzhelian The Gzhelian ( ) is an age in the ICS geologic timescale or a stage in the stratigraphic column. It is the youngest stage of the Pennsylvanian, the youngest subsystem of the Carboniferous. The Gzhelian lasted from to Ma. It follows the Kas ...

. References appear in scientific literature to a Stephanian epoch or Stephanian

reflecting the stage's earlier status.

References

{{Geological history, p, p, state=collapsed Carboniferous geochronology Pennsylvanian geochronology . Gzhelian Stratigraphy of Europe