Gzhelium

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system Subsystem step ≈ age ( mya )
higher higher higher younger
Carbon Pennsylvania Gzhelium 298.9
⬍
303.7
Kasimovium 303.7
⬍
307
Moskovium 307
⬍
315.2
Bashkirium 315.2
⬍
323.2
Mississippium Serpukhovium 323.2
⬍
330.9
Visa 330.9
⬍
346.7
Tournaisium 346.7
⬍
358.9
deeper deeper deeper older

The Gzhelium (also Gschel or Gsel stage) is the highest chronostratigraphic stage of the Pennsylvania ( carbon ) in the history of the earth . The stage lasted geochronologically from about 303.7 million to about 298.9 million years. The Gzhelium is preceded by the Kasimovium , it is followed by the Asselium , the lowest level of the Permian .

Naming and history

The Gzhelium is named after the Russian village Gzhel (Russian Гжель ) near Ramenskoye not far from Moscow . The name and level were proposed by Sergei Nikitin (1850-1909) in 1890 .

Definition and GSSP

The base of the Gzheliums is close to the first appearance of fusulinids genera Daixina , Jigulites and Rugosofusulina , or Erstvorkommen the Conodonten -type Streptognathodus Zethus . The end of the stage is the first appearance of the conodont species Streptognathodus isolatus within the Streptognathus "wabaunsensis" conodont chronocline. The fusuline species Sphaeroschwagerina vulgaris aktjubensis appears 6 m higher in profile . A reference profile ( GSSP = Global Stratotype Section and Point) for the basis of the Gzhelium has not yet been established. The Ussolka (Usolka) profile is proposed (after the Ussolka , a small right tributary of the Belaja ) about 120 km southeast of Ufa and about 60 km northeast of Sterlitamak on the northern edge of the settlement Krasnoussolski ( Bashkortostan , Russia ).

Breakdown

The Gzhelium is subdivided into five conodont zones:

literature

  • Felix Gradstein, James Ogg & Alan Smith: A Geologic Time Scale. Cambridge University Press 2004, ISBN 0-521-78142-6 .
  • Hans Murawski & Wilhelm Meyer: Geological dictionary . 10., rework. u. exp. Ed., 278 pages, Enke Verlag, Stuttgart 1998, ISBN 3-432-84100-0 .
  • Vladimir I. Davydov, Brian F. Glenister, Claude Spinosa, Scott M. Ritter, VV Chernykh, BR Wardlaw and WS Snyder: Proposal of Aidaralash as Global Stratotype Section and Point (GSSP) for base of the Permian System . In: Episodes. 21 (1): 11-18, Beijing 1998 ISSN  0705-3797 PDF; 304 kB
  • Valery V. Chernykh, Boris I. Chuvashov, Vladimir I. Davydov, Mark Schmitz & Walter S. Snyder: Usolka section (southern Urals, Russia): a potential candidate for GSSP to define the base of the Gzhelian Stage in the global chronostratigraphic scale , Geologija, 49 (2): 205-217, Ljubljana 2006 PDF; 1.22 MB

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