In the

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 geochron ...

, the Wordian is an

age Age or AGE may refer to: Time and its effects * Age, the amount of time someone has been alive or something has existed ** East Asian age reckoning, an Asian system of marking age starting at 1 * Ageing or aging, the process of becoming older ...

or stage of the

Permian The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years, from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the s ...

. It is the middle of three subdivisions of the

Guadalupian The Guadalupian is the second and middle Series (stratigraphy), series/Epoch (geology), epoch of the Permian. The Guadalupian was preceded by the Cisuralian and followed by the Lopingian. It is named after the Guadalupe Mountains of New Mexico an ...

Epoch In chronology and periodization, an epoch or reference epoch is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured. The moment of epoch is usually decided b ...

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 i ...

. The Wordian lasted between and million years ago (Ma). It was preceded by the Roadian and followed by the

Capitanian In the geologic timescale, the Capitanian is an age or stage of the Permian. It is also the uppermost or latest of three subdivisions of the Guadalupian Epoch or Series. The Capitanian lasted between and million years ago. It was preceded by t ...

Stratigraphy

The Wordian Stage was introduced into scientific literature by Johan August Udden in 1916 and was named after the

Word Formation In linguistics, word formation is an ambiguous term that can refer to either: * the processes through which words can change (i.e. morphology), or * the creation of new lexemes in a particular language Morphological A common method of word form ...

of the North American Permian Basin. The Wordian was first used as a stratigraphic subdivision of the Guadalupian in 1961, when both names were still only used regionally in the southern US. The stage was added to the internationally used ISC timescale in 2001.; 1999: ''Proposal of Guadalupian and Component Roadian, Wordian and Capitanian Stages as International Standards for the Middle Permian Series'', Permophiles 34: pp 3–11. The base of the Wordian Stage is defined as the place in the stratigraphic record where fossils of

conodont Conodonts, are an extinct group of marine jawless vertebrates belonging to the class Conodonta (from Ancient Greek κῶνος (''kōnos''), meaning " cone", and ὀδούς (''odoús''), meaning "tooth"). They are primarily known from their hard ...

species ''

Jinogondolella ''Jinogondolella'' is an extinct genus of conodonts. Mesogondolella and Jinogondolella (Conodonta): Multielement definition of the taxa that bracket the basal Guadalupian The Guadalupian is the second and middle Series (stratigraphy), series/ ...

aserrata'' first appear. The global reference profile for this stratigraphic boundary is located at Getaway Ledge in the Guadalupe Mountains of

Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...

. The top of the Wordian (the base of the Capitanian Stage) is defined as the place in the stratigraphic record where the conodont species ''Jinogondolella postserrata'' first appears. The Wordian stage was part of the time in which the

Zechstein The Zechstein ( German either from ''mine stone'' or ''tough stone'') is a unit of sedimentary rock layers of Late Permian ( Lopingian) age located in the European Permian Basin which stretches from the east coast of England to northern Poland. T ...

was deposited in Europe.

Biostratigraphy

The Wordian spans the entire conodont biozone of ''Jinogondolella aserrata''. It contains two fusulinid biozones: *Zone of ''Afganella tereshkovae'' *Zone of ''Neoschwagerina tenuis''

Wordian life

Olson’s Extinction, a worldwide loss of terrestrial vertebrate life occurred during the Early Guadalupian ( Roadian, Wordian).

Notable formations

* Gnishik Formation (

Armenia Armenia, officially the Republic of Armenia, is a landlocked country in the Armenian Highlands of West Asia. It is a part of the Caucasus region and is bordered by Turkey to the west, Georgia (country), Georgia to the north and Azerbaijan to ...

, Azerbaidjan,

Iran Iran, officially the Islamic Republic of Iran (IRI) and also known as Persia, is a country in West Asia. It borders Iraq to the west, Turkey, Azerbaijan, and Armenia to the northwest, the Caspian Sea to the north, Turkmenistan to the nort ...

) *

(

, United States)

References

Literature

External links

GeoWhen Database - WordianUpper Paleozoic stratigraphic chart
at the website of the subcommission for stratigraphic information of the ICS {{Geological history, p, p Permian geochronology . Permian geology of Texas