Capitanian
Encyclopedia
In the geologic timescale, the Capitanian is an age or stage of the Permian
Permian
The PermianThe term "Permian" was introduced into geology in 1841 by Sir Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil; Murchison asserted in 1841 that he named his "Permian...

. It is also the uppermost or latest of three subdivisions of the Guadalupian epoch
Epoch (geology)
An epoch is a subdivision of the geologic timescale based on rock layering. In order, the higher subdivisions are periods, eras and eons. We are currently living in the Holocene epoch...

 or series
Series (stratigraphy)
Series are subdivisions of rock layers made based on the age of the rock and corresponding to the dating system unit called an epoch, both being formally defined international conventions of the geological timescale. A series is therefore a sequence of rock depositions defining a...

. The Capitanian lasted between and . It was preceded by the Wordian
Wordian
In the geologic timescale, the Wordian is an age or stage of the Permian. It is the middle of three subdivisions of the Guadalupian epoch or series. The Wordian lasted between 268.0 ± 0.7 and 265.8 ± 0.7 million years ago...

 and followed by the Wuchiapingian
Wuchiapingian
In the geologic timescale, the Wuchiapingian or Wujiapingian is an age or stage of the Permian. It is also the lower or earlier of two subdivisions of the Lopingian epoch or series. The Wuchiapingian spans the time between 260.4 ± 0.7 and 253.8 ± 0.7 million years ago...

.

A significant mass extinction event occurred at the end of this stage which may be related to the much larger Permian-Triassic extinction event
Permian-Triassic extinction event
The Permian–Triassic extinction event, informally known as the Great Dying, was an extinction event that occurred 252.28 Ma ago, forming the boundary between the Permian and Triassic geologic periods, as well as the Paleozoic and Mesozoic eras...

 that followed about 10 million years later.

Stratigraphy

The Capitanian stage was introduced into scientific literature by George Burr Richardson in 1904. The name comes from the Capitan Reef in the Guadalupe Mountains
Guadalupe Mountains
The Guadalupe Mountains are a mountain range located in West Texas and southeastern New Mexico. The range includes the highest summit in Texas, Guadalupe Peak, , and the "signature peak" of West Texas, El Capitan, both located within Guadalupe Mountains National Park, as well as Carlsbad Caverns...

 (Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...

, USA). The Capitanian 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
International Commission on Stratigraphy
The International Commission on Stratigraphy , sometimes referred to by the unofficial "International Stratigraphic Commission" is a daughter or major subcommittee grade scientific daughter organization that concerns itself with stratigraphy, geological, and geochronological matters on a global...

 timescale in 2001.

Definitions

The base of the Capitanian stage is defined as the place in the stratigraphic record where fossils of conodont
Conodont
Conodonts are extinct chordates resembling eels, classified in the class Conodonta. For many years, they were known only from tooth-like microfossils now called conodont elements, found in isolation. Knowledge about soft tissues remains relatively sparse to this day...

 species Jinogondolella postserrata first appear. The global reference profile for this stratigraphic boundary is located at Nipple Hill in the southern Guadalupe Mountains of Texas.

The top of the Capitanian (the base of the Wuchiapingian and Lopingian series) is defined as the place in the stratigraphic record where the conodont species Clarkina postbitteri postbitteri first appears.

The Capitanian stage was part of the time in which the Zechstein
Zechstein
The Zechstein is a unit of sedimentary rock layers of Middle to Late Permian age located in the European Permian Basin which stretches from the east coast of England to northern Poland...

 was deposited in Europe. It is coeval with the old European regional Saxonian stage. In the eastern Tethys domain
Tethys Ocean
The Tethys Ocean was an ocean that existed between the continents of Gondwana and Laurasia during the Mesozoic era before the opening of the Indian Ocean.-Modern theory:...

, the Capitanian overlaps the regional Murgabian stage, the Midian stage and the lower part of the Laibinian stage. In Russia the Capitanian equals the lower part of the regional Severodvinian stage.

Biostratigraphy

The Capitanian contains one ammonite
Ammonite
Ammonite, as a zoological or paleontological term, refers to any member of the Ammonoidea an extinct subclass within the Molluscan class Cephalopoda which are more closely related to living coleoids Ammonite, as a zoological or paleontological term, refers to any member of the Ammonoidea an extinct...

 biozone
Biozone
Biostratigraphic units or Biozones are intervals of geological strata that are defined on the basis of their characteristic fossil taxa....

 (Timorites) and three conodont biozones:
  • zone of Clarkina postbitteri hongshuiensis
  • zone of Jinogondolella altudaensis
  • zone of Jinogondolella postserrata


Larger fusulinid species permit a division in two biozones:
  • zone of Rausserella
  • zone of Afganella schenki

Biodiversity

Olson’s Extinction, in the Early Guadalupian (Roadian, Wordian), reveals an extended period of low diversity when worldwide two-thirds of terrestrial vertebrate life was lost. Global diversity rose
dramatically in the Capitanian, probably the result of disaster taxa filling empty guilds, only to fall again when the end-Guadalupian event caused a diversity drop in the Wuchiapingian.

Events

Carbon isotopes in marine
Marine (ocean)
Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...

 limestone
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....

 from of Capitanian age show an increase in δ13C values. The change in carbon isotopes in the sea water reflects cooling of global climates
Climate change
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...

.

This climatic cooling may have caused the end-Capitanian extinction event among species that lived in warm water, like larger fusulinid
Fusulinid
The Fusulinida is an extinct order within the Foraminifera in which the tests are composed of tightly packed, secreted microgranular calcite. In advanced forms the test wall is differentiated into two or more layers...

s (Verbeekninidae), large bivalves (Alatoconchidae and Rugosa
Rugosa
Disambiguation:The Rugosa Rose is also sometimes just called "Rugosa". For the moon in Star Wars: The Clone Wars, see .The Rugosa, also called the Tetracoralla, are an extinct order of coral that were abundant in Middle Ordovician to Late Permian seas.Solitary rugosans are often referred to...

 corals, and Waagenophyllidae.

Literature

; 1961: The Permian ammonoids of Australia, Journal of Paleontology 35(4), pp 673–736.; 1999: Proposal of Guadalupian and Component Roadian, Wordian and Capitanian Stages as International Standards for the Middle Permian Series, Permophiles 34: pp 3–11.; 2004: A Geologic Time Scale 2004, Cambridge University Press; 2007: The Capitanian (Permian) Kamura cooling event: The beginning of the Paleozoic–Mesozoic transition, Palaeoworld 16, p. 16-30.

External links

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