Changhsingium

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system series step ≈ age ( mya )
higher higher higher younger
Perm Lopingium Changhsingium 251.9
⬍
254.2
Wuchiapingium 254.2
⬍
259.9
Guadalupium Capitanium 259.9
⬍
265.1
Wordium 265.1
⬍
268.8
Roadium 268.8
⬍
272.3
Cisuralium Kungurium 272.3
⬍
279.3
Artinskium 279.3
⬍
290.1
Sacmarium 290.1
⬍
295.5
Asselium 295.5
⬍
298.9
deeper deeper deeper older

The Changhsingium (less commonly also Changxingium) is the highest chronostratigraphic level of the Upper Permian or Lopingium in the history of the earth . The stage begins geochronologically about 254.2 million years ago and ends about 251.9 million years ago. The Changhsingium follows the Wuchiapingium and is replaced by the Indusium , the lowest level of the Triassic .

Naming and history

The Changhsingium is named after Changxing ( W.-G. Ch'ang-hsing ), Zhejiang Province , China, in the vicinity of which the GSSP was established and after the Changxing Limestone named after the city by Grabau (1923). Furnish and Glenister (1970) suggested adopting this name for a chronostratigraphic unit. Zhao et al. (1981) then formally proposed the Changhsingium as a chronostratigraphic level. In 2005 the IUGS ratified the Changhsingium as a global chronostratigraphic level.

Definition and GSSP

The basis of the Changhsiangium is defined by the first appearance of the conodont species Clarkina wangi . The end of the stage is marked with the first appearance of the conodont species Hindeodus parvus . The GSSP (globally valid type locality and type profile) is the Meishan Profile D near Changxing ( W.-G. Ch'ang-hsing ), Zhejiang Province , China.

Breakdown

The Changhsingian includes only one ammonite zone, the Iranites zone.

Formations

During the Changhsingium, the Bellerophon Formation was deposited in the Southern Alps . Shortly before the Permian-Triassic border , the Zechstein sedimentation came to an end in northern Central Europe.

Fossils

fishes

In the cartilaginous fish (Chondrichthyes) the order Petalodontiformes , which had existed since the Mississippian , and the suborder Menaspoidei, which had also been present since the Mississippian, were extinct. The orders Ctenacanthiformes (from Devonian ), Eugeneodontida (from Mississippium) and Xenacanthiformes (from Devonian) continued to exist . Among the bony fish (Osteichthyes) the order Dorypteriformes , which existed from the lower Permian, succumbed . The suborders Palaeonisciformes (from the uppermost Silurian ) and Platysomoidei (from Mississippian) also existed. The Semionotiformes order was newly developed .

Examples among the cartilaginous fish of the Changhsingium are:

  • Fadenia

  • Hybodus fraasi

  • Menaspis armata and Deltoptychius

  • Orthacanthus senckenbergianus

  • Sarcoprion edax

  • Vodnika striatula

And among the bony fish:

  • Elonichthys peltigerus

  • Palaeoniscum free life i

  • Platysomus circularis

Terrestrial vertebrates

Among the amphibians , the two superfamilies Eryopoidea (from Pennsylvania ) and Trimerorhachoidea (from Mississippian) were extinguished. The families Chroniosuchidae , Kotlassiidae and Lanthanosuchidae , which only occur in the Upper Permian, continued to exist . The two superfamilies Brachyopoidea and Rhinesuchoidea were a new development .

Some examples of the amphibians of the Changhsingian:

  • Bystrowiana permica

  • Chroniosuchus paradoxus

  • Dvinosaurus parvus

  • Karpinskiosaurus secundus

  • Kotlassia great

  • Melosaurus platyrhinus

  • Peltobatrachus pustulatus

  • Rhinesuchus

  • Uralerpeton tverdokhlebovae

  • Zygosaurus

In the case of reptiles , the orders Captorhinida (from Lower Permian) and Mesosauria (from Middle Permian) became extinct. The families Caseidae (from Middle Permian) and Varanopseidae (also from Middle Permian) disappeared under the order Pelycosauria . The families Coelurosauravidae (from Upper Permian) and Paliguanidae (also from Upper Permian), the order Eosuchia (from Upper Permian), the suborders Dicynodontia (from Upper Permian), Proterosuchia (from Upper Permian) and Therocephalia (from Upper Permian) as well the superfamily Procolophonoidea (from Upper Permian). The suborder Cynodontia was newly created , from which the mammals would later emerge. At the end of the Changhsingian the suborders Dinocephalia (from Upper Permian), Eotitanosuchia (from Middle Permian), Gorgonopsia (from Upper Permian), Millerosauroidea (from Upper Permian) and Pareiasauroidea (also from Upper Permian) disappeared .

The Changhsingium includes the following reptiles:

  • Acerosodontosaurus piveteaui

  • Anthodon gregoryi

  • Daptocephalus leoniceps

  • Diictodon

  • Elginia mirabilis

  • Ennatosaurus tecton

  • Hovasaurus boulei

  • Milleretta rubidgei

  • Millerosaurus pricei

  • Nanoparia luckhoffi

  • Nyctiphruretus acudens

  • Owenetta kitchingorum

  • Rubidgea atrox

  • Scutosaurus karpinskii

  • Thadeosaurus colcanapi

  • Theriognathus

Individual evidence

  1. ↑ for another dating of the Permian / Triassic boundary see Brack et al. (2005): 252.6 million years.
  2. ↑ Yugan Jin et al. P. 175.

literature

  • Peter Brack, Hans Rieber, Alda Nicora and Roland Mundil: The Global boundary Stratotype Section and Point (GSSP) of the Ladinian Stage (Middle Triassic) at Bagolino (Southern Alps, Northern Italy) and its implications for the Triassic time scale. In: Episodes. 28 (4): 233-244, Beijing 2005 ISSN  0705-3797 PDF .
  • Yugan Jin , Yue Wang, Charles Henderson, Bruce R. Wardlaw, Shuzhong Shen and Changqun Cao: The Global Boundary Stratotype Section and Point (GSSP) for the base of Changhsingian Stage (Upper Permian). Episodes, 29 (3): 175-182, Beijing 2006 ISSN  0705-3797 PDF
  • Felix Gradstein, Jim Ogg, Jim & Alan Smith: A Geologic timescale. Cambridge University Press 2005, ISBN 9780521786737
  • JK Zhao, JZ Sheng, ZQ Yao, XL Liang, CZ Chen, L. Rui and AT Liao: The Changhsingian and Permian-Triassic boundary of South China. Bulletin of the Nanjing Institute of Geology and Palaeontology, Academia Sinica 2: 1-112, Nanjing 1981.

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