| Kungurian | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 283.5 ± 0.6 – 273.01 ± 0.14Ma | |||||||||||||
| Chronology | |||||||||||||
| |||||||||||||
| Etymology | |||||||||||||
| Name formality | Formal | ||||||||||||
| Usage information | |||||||||||||
| Celestial body | Earth | ||||||||||||
| Regional usage | Global (ICS) | ||||||||||||
| Time scale(s) used | ICS Time Scale | ||||||||||||
| Definition | |||||||||||||
| Chronological unit | Age | ||||||||||||
| Stratigraphic unit | Stage | ||||||||||||
| Time span formality | Formal | ||||||||||||
| Lower boundary definition | Not formally defined | ||||||||||||
| Lower boundary definition candidates | NearFAD of theConodontNeostreptognathodus pnevi | ||||||||||||
| Lower boundary GSSP candidate section(s) | Mechetlino,Southern Ural Mountains,Russia | ||||||||||||
| Upper boundary definition | FAD of the ConodontJinogondolella nanginkensis | ||||||||||||
| Upper boundary GSSP | Stratotype Canyon,Guadalupe Mountains,Texas,U.S.A. 31°52′36″N104°52′36″W / 31.8767°N 104.8768°W /31.8767; -104.8768 | ||||||||||||
| Upper GSSP ratified | 2001[2] | ||||||||||||
In thegeologic timescale, theKungurian is anage orstage of thePermian. It is the latest or upper of four subdivisions of theCisuralianEpoch orSeries. The Kungurian lasted between 283.3 and 274.4million years ago (Ma). It was preceded by theArtinskian and followed by theRoadian.[3]
The Kungurian is named after the Russian city ofKungur inPerm Krai. The stage was introduced into scientific literature by Russian geologist Alexandr Antonovich Stukenberg (Alexander Stuckenberg) in 1890.[4]
The base of the Kungurian Stage is defined as the place in the stratigraphic record where fossils ofconodont speciesNeostreptognathodus pnevi andNeostreptognathodus exculptus first appear. As of 2009, there was no agreement yet on a global reference profile (aGSSP) for the base of the Kungurian. The top of the Kungurian (the base of the Roadian and theGuadalupian series) is defined as the place in the stratigraphic record where fossils of conodont speciesJinogondolella nanginkensis first appear.
The Kungurian contains three conodontbiozones:
The Kungurian is the last stage in which many Permo-Carboniferous clades of vertebrates (Seymouria,ophiacodontids,edaphosaurids, etc.) occur in the fossil record, and the end of this stage whitnessed one of the greatest faunal turnovers of thePermian.[5] Early studies placedOlson’s Extinction just after the Kungurian,[6] but more recent studies only indicate that this possible extinction event is located around Kungurian/Roadian boundary.[7][8] Howerver, higher-resolution stratigraphic data suggest that this even is actually a slow decline over 20 Ma that started in theSakmarian and that may have extended into theRoadian, with many lineages of early synapsids becoming extinct in the Kungurian.[9][10] However, assessment of the exact timing of these extinctions is hampered by a gap in the fossil record of continental vertebrates in the late Kungurian, at least in Texas and Oklahoma, two states that have an unparalleled fossil record of such taxa for the early to mid-Kungurian.[11]
