Pridolium

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system series step ≈ age ( mya )
higher higher higher younger
Silurian Pridolium 419.2
⬍
423
Ludlow Ludfordium 423
⬍
425.6
Gorstium 425.6
⬍
427.4
Wenlock Homerium 427.4
⬍
430.5
Sheinwoodium 430.5
⬍
433.4
Llandovery Telychium 433.4
⬍
438.5
Aeronium 438.5
⬍
440.8
Rhuddanium 440.8
⬍
443.4
deeper deeper deeper older

The Pridolium (also shortened Pridoli , Czech : Přídolí) is the most recent chronostratigraphic series of the Silurian in the history of the earth . The pridolium begins geochronologically about 423 million years ago and ends about 419.2 million years ago. It replaces the Silurian level of the Ludfordium or the series of the Ludlow and is followed by the Devonian level of the Lochkovium . The pridolium is not divided into stages.

Naming and history

The series is named after a corridor location in the Homolka a Přídolí nature reserve near the Slivenec district in the south of Prague . This name was given in 1948 by Ferdinand Prantl and Alois Přibyl. There are old quarries here. The current representative digestion ( Global Boundary Stratotype Section and Point ), however, is about 3.5 kilometers north-west of it on the edge of the district settlement Řeporyje in the hallway Na Požárech (locality Požáry ) where extensive quarries are.

Definition and GSSP

The base of the Pridoli is defined with the first appearance of the graptolite species Monograptus parultimus . The Pridoli (and thus also the Silurian) ends with the first appearance of the graptolite species Monograptus uniformis . The Požáry profile in the Daleje Valley near Prague (Czech Republic) was selected as the reference profile ( GSSP = Global Stratotype Section and Point) for the Pridolium .

Breakdown

The pridolium is not divided into further geological levels:

Flor development

Artist impression of Cooksonia

This epoch was characterized, among other things, by the further development of the first vascular plants such as Cooksonia , which grew in swampy shallow water areas, especially around the later continent Laurussia . Fossils of these plants have been found in numerous places, for example in Poland.

Individual evidence

  1. ↑ Brief description Homolka a Přídolí (Czech)
  2. ↑ Štěpán Manda, Jiří Frýda: Silurian-Devonian boundary events and their influence on cephalopod evolution: evolutionary significance of cephalopod egg size during mass extinctions. In: Bulletin of Geoscience. Vol. 85 (2010) issue 3, pp. 513-540 (PDF; 6.6 MB)
  3. ↑ Brief description of the reference point (English)

literature

  • Ivo Chlupác and Z. Kukal: The boundary stratotype at Klonk. The Silurian-Devonian Boundary. IUGS Series, A5: 96-109, Berlin 1977 ISSN  0374-8480
  • Ivo Chlupác and Frantisek Vacek: Thirty years of the first international stratotype: The Silurian-Devonian boundary at Klonk and its present status. Episodes, 26 (3): 10-15, Beijing 2003 ISSN  0705-3797
  • Felix Gradstein, Jim Ogg & Alan Smith: A Geologic timescale. Cambridge University Press 2004 ISBN 978-0-521-78673-7
  • J. Kríz: 1989. The Přídoli Series in the Prague Basin (Barrandium area, Bohemia). In: Holland, CH and Bassett, MG (eds.). A global standard for the Silurian System. National Museum of Wales, Geological Series, 9: 90-100, Cardiff ZDB -ID & key = zdb 995874-5 .

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