Kungurian
   HOME

TheInfoList



OR:

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 geochronol ...
, the Kungurian 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 ...
or stage of the Permian. It is the latest or upper of four subdivisions of the
Cisuralian The Cisuralian is the first Series (stratigraphy), series/Epoch (geology), epoch of the Permian. The Cisuralian was preceded by the Pennsylvanian (geology), Pennsylvanian and followed by the Guadalupian. The Cisuralian Epoch is named after the w ...
Epoch or Series. The Kungurian lasted between and million years ago (Ma). It was preceded by the Artinskian and followed by the Roadian.


Stratigraphy

The Kungurian is named after the Russian city of Kungur in Perm Krai. The stage was introduced into scientific literature by Russian geologist Alexandr Antonovich Stukenberg (Alexander Stuckenberg) in 1890.; 2002: ''Progress report on the base of the Artinskian and base of the Kungurian by the Cisuralian Working Group'', Permophiles 41: pp 13–16. The base of the Kungurian Stage is defined as the place in the stratigraphic record where fossils of
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, which ...
species ''
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 Permia ...
pnevi'' and ''Neostreptognathodus exculptus'' first appear. As of 2009, there was no agreement yet on a global reference profile (a GSSP) for the base of the Kungurian. The top of the Kungurian (the base of the Roadian and the Guadalupian series) is defined as the place in the stratigraphic record where fossils of conodont species '' Jinogondolella nanginkensis'' first appear. The Kungurian contains three conodont biozones: *zone of ''Neostreptognathodus sulcoplicatus'' *zone of ''Neostreptognathodus prayi'' *zone of ''Neostreptognathodus pnevi''


Kungurian life

The Kungurian is the last stage in which many Permo-Carboniferous clades of vertebrates ('' Seymouria'',
ophiacodontids Ophiacodontidae is an extinct family (biology), family of early eupelycosauria, eupelycosaurs from the Carboniferous and Permian. ''Archaeothyris'', and ''Clepsydrops'' were among the earliest ophiacodontids, appearing in the Late Carboniferous. ...
, edaphosaurids, etc.) occur in the fossil record, and the end of this stage whitnessed one of the greatest faunal turnovers of the Permian. Early studies placed Olson’s Extinction just after the Kungurian, but more recent studies only indicate that this possible extinction event is located around Kungurian/ Roadian boundary. Howerver, higher-resolution stratigraphic data suggest that this even is actually a slow decline over 20 Ma that started in the Sakmarian and that may have extended into the Roadian, with many lineages of early synapsids becoming extinct in the Kungurian. 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.


References


External links


GeoWhen Database - Kungurian

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