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 geochr ...

, the Sakmarian is an

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

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 * Sta ...

of the

Permian The Permian ( ) is a geologic period and 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 251.9 Mya. It is the last period of the Paleoz ...

. It is a subdivision of the Cisuralian

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 by ...

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 Sakmarian lasted between 293.52 and million years ago (Ma). It was preceded by the

Asselian In the geologic timescale, the Asselian is the earliest geochronologic age or lowermost chronostratigraphic stage of the Permian. It is a subdivision of the Cisuralian Epoch or Series. The Asselian lasted between and million years ago (Ma) ...

and followed by the

Artinskian In the geologic timescale, the Artinskian is an age or stage of the Permian. It is a subdivision of the Cisuralian Epoch or Series. The Artinskian likely lasted between and million years ago (Ma) according to the most recent revision of th ...

.; 2004: ''A Geologic Time Scale 2004'',

Cambridge University , mottoeng = Literal: From here, light and sacred draughts. Non literal: From this place, we gain enlightenment and precious knowledge. , established = , other_name = The Chancellor, Masters and Schola ...

Press

Stratigraphy

The Sakmarian Stage is named after the

Sakmara River The Sakmara (russian: Сакмара; ba, Һаҡмар, Haqmar) is a river in Russia that drains the southern tip of the Ural Mountains south into the river Ural. It is long, and has a drainage basin of . It is a right tributary of the Ural, whic ...

in the

Ural Mountains The Ural Mountains ( ; rus, Ура́льские го́ры, r=Uralskiye gory, p=ʊˈralʲskʲɪjə ˈɡorɨ; ba, Урал тауҙары) or simply the Urals, are a mountain range that runs approximately from north to south through western ...

, a

tributary A tributary, or affluent, is a stream or river that flows into a larger stream or main stem (or parent) river or a lake. A tributary does not flow directly into a sea or ocean. Tributaries and the main stem river drain the surrounding drainage ...

to the

Ural River The Ural (russian: Урал, ), known before 1775 as Yaik (russian: Яик, ba, Яйыҡ, translit=Yayıq, ; kk, Жайық, translit=Jaiyq, ), is a river flowing through Russia and Kazakhstan in the continental border between Europe and Asia ...

. The stage was introduced into scientific literature by

Alexander Karpinsky Alexander Petrovich Karpinsky (russian: Александр Петрович Карпинский, trl. Aljeksandr Pjetrovič Karpinskij; 7 January 1847 ( NS) – 15 July 1936) was a prominent Russian and Soviet geologist and mineralogist, and ...

in 1874. In Russian stratigraphy, it originally formed a substage of the Artinskian Stage. Currently, the ICS uses it as an independent stage in its international geologic timescale. The base of the Sakmarian Stage is laid with the first appearance of conodont species ''

Streptognathodus ''Streptognathodus'' is an extinct genus of conodonts from the Late Carboniferous to Early Permian. Use in stratigraphy Late Carboniferous The top of the Kasimovian stage is close to the first appearance of ''Streptognathodus zethus''. T ...

postfusus'' in the fossil record. A global reference profile for the base (a

GSSP A Global Boundary Stratotype Section and Point (GSSP) is an internationally agreed upon reference point on a stratigraphic section which defines the lower boundary of a stage on the geologic time scale. The effort to define GSSPs is conducted ...

), located in the southern Ural Mountains, Russia, was ratified in 2018. The top of the Sakmarian (the base of the Artinskian) is defined as the place in the stratigraphic record where fossils of conodont species ''

Sweetognathus ''Sweetognathus'' is an extinct genus of conodonts in the family Sweetognathidae that evolved at the beginning of the Permian period (298.9 Ma), in near-equatorial, shallow-water seas. The genus is characterized by pustulose ornamentation on a ...

whitei'' and ''

Mesogondolella ''Mesogondolella'' is an extinct genus of conodonts. The species ''M. daheshenensis'' and ''M. subgracilis'' are from the Permian (probably Wordian) of the Daheshen Formation in China.The age of the Daheshen Formation in Jilin Province based o ...

bisselli'' first appear.

References

External links

GeoWhen Database - Sakmarian

Upper Paleozoic stratigraphic chart
at the website of the subcommission for stratigraphic information of the ICS {{Geological history, p, p Permian geochronology .