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 Artinskian is an age or stage 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 Paleo ...

. It is a subdivision of the

Cisuralian The Cisuralian is the first series/epoch of the Permian. The Cisuralian was preceded by the Pennsylvanian and followed by the Guadalupian. The Cisuralian Epoch is named after the western slopes of the Ural Mountains in Russia and Kazakhstan and ...

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 ...

or Series. The Artinskian likely lasted between and million years ago (Ma) according to the most recent revision of the

International Commission on Stratigraphy The International Commission on Stratigraphy (ICS), sometimes referred to unofficially as the "International Stratigraphic Commission", is a daughter or major subcommittee grade scientific daughter organization that concerns itself with stratigr ...

(ICS) in 2022. It was preceded by the Sakmarian and followed by the Kungurian.

Stratigraphy

Jimbacrinus bostocki MHNT Gascoyne Junction, Western Australia

The Artinskian is named after the small

Russia Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-ei ...

n city of Arti (formerly ''Artinsk''), situated in the southern

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 ...

, about 200 km southwest of

Yekaterinburg Yekaterinburg ( ; rus, Екатеринбург, p=jɪkətʲɪrʲɪnˈburk), alternatively romanized as Ekaterinburg and formerly known as Sverdlovsk ( rus, Свердло́вск, , svʲɪrˈdlofsk, 1924–1991), is a city and the administra ...

. 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.

Base of the Artinskian

The base of the Artinskian Stage is defined as the

first appearance datum First appearance datum (FAD) is a term used by geologists and paleontologists to designate the first appearance of a species in the geologic record. FADs are determined by identifying the geologically oldest fossil discovered, to date, of a particu ...

(FAD) of the

conodont Conodonts ( Greek ''kōnos'', " cone", + ''odont'', "tooth") are an extinct group of agnathan (jawless) vertebrates resembling eels, classified in the class Conodonta. For many years, they were known only from their tooth-like oral elements, whi ...

species ''

Sweetognathus whitei ''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 ...

'' and '' Mesogondolella bisselli''. In order to constrain this age, the ICS subcommission on Permian

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: lithost ...

informally proposed a candidate

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 ...

in 2002, later followed by a formal proposal in 2013. The proposed GSSP location - the Dal'ny Tulkas roadcut in the

Southern Ural Southern Ural - the south, the widest part of the Ural Mountains, stretches from the river Ufa (near the village of Lower Ufaley) to the Ural River. From the west and east the Southern Ural is limited to the East European, West Siberian Plain and ...

s, near the town of Krasnousolsky - was eventually ratified in February 2022. U-Pb radiometric dating found that the base of the Artinskian was approximately 290.1 million years old (Ma), based on the position of the rock layer at the Dal'ny Tulkas roadcut containing the FAD of S''. whitei'' relative to three precisely dated ash beds surrounding it. Earlier radiometric reported a much younger age of 280.3 Ma for the Sakmarian-Artinskian boundary.

Top of the Artinskian

The top of the Artinskian (and the base of the Kungurian) is defined as the place in the stratigraphic record where fossils of conodonts ''

Neostreptognathodus ''Neostreptognathodus'' is an extinct genus of conodonts from the Cisuralian (Early Permian). Use in stratigraphy The top of the Artinskian (the base of the Kungurian In the geologic timescale, the Kungurian is an age or stage of the Perm ...

pnevi'' and ''Neostreptognathodus exculptus'' first appear.

Artinskian Warming Event

Around 287 million years ago occurred an interval of pronounced warming known as the Artinskian Warming Event (AWE). This period of

global warming In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to ...

accelerated the

deglaciation Deglaciation is the transition from full glacial conditions during ice ages, to warm interglacials, characterized by global warming and sea level rise due to change in continental ice volume. Thus, it refers to the retreat of a glacier, an ice shee ...

that had been occurring since the Sakmarian following the end of the most intense

glacial A glacial period (alternatively glacial or glaciation) is an interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate betwe ...

phase of the Late Palaeozoic Ice Age. In addition, it is also associated with significant

global drying Land surface effects on climate are wide-ranging and vary by region. Deforestation and exploitation of natural landscapes play a significant role. Some of these environmental changes are similar to those caused by the effects of global warming. De ...

, which had gradually been occurring since the Carboniferous-Permian boundary. Major aridification during the AWE is evidenced by a positive δ¹⁸O excursion observed in

brachiopod Brachiopods (), phylum Brachiopoda, are a phylum of trochozoan animals that have hard "valves" (shells) on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, w ...

fossils A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

, with arid and semi-arid conditions expanding across much of Pangaea as

glaciers A glacier (; ) is a persistent body of dense ice that is constantly moving under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires distinguishing features, such as ...

receded to refugia in the polar regions of

Gondwana Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final sta ...

References

External links

GeoWhen Database - Artinskian

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