Lochkovian | |||||||||||||||||
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Chronology | |||||||||||||||||
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Etymology | |||||||||||||||||
Name formality | Formal | ||||||||||||||||
Name ratified | 1985[5] | ||||||||||||||||
Usage information | |||||||||||||||||
Celestial body | Earth | ||||||||||||||||
Regional usage | Global (ICS) | ||||||||||||||||
Time scale(s) used | ICS Time Scale | ||||||||||||||||
Definition | |||||||||||||||||
Chronological unit | Age | ||||||||||||||||
Stratigraphic unit | Stage | ||||||||||||||||
Time span formality | Formal | ||||||||||||||||
Lower boundary definition | FAD of the graptolite Monograptus uniformis | ||||||||||||||||
Lower boundary GSSP | Klonk, Prague, Czech Republic 49°51′18″N 13°47′31″E / 49.8550°N 13.7920°E | ||||||||||||||||
Lower GSSP ratified | 1972[6] | ||||||||||||||||
Upper boundary definition | FAD of the conodonts Eognathodus sulcatus and Latericriodus steinachensis Morph beta | ||||||||||||||||
Upper boundary GSSP | Velká Chuchle quarry, Velká Chuchle, Prague, Czech Republic 50°00′53″N 14°22′21″E / 50.0147°N 14.3726°E | ||||||||||||||||
Upper GSSP ratified | 1989[5] |
The Lochkovian is one of three faunal stages in the Early Devonian Epoch. It lasted from 419.2 ± 3.2 million years ago to 410.8 ± 2.8 million years ago. It marked the beginning of the Devonian Period, and was followed by the Pragian Stage. It is named after the village of Lochkov in the Czech Republic, now part of the city of Prague.[7] The GSSP is located within the Lochkow Formation at the Klonk Section in Prague.
In North America the Lochkovian Stage is represented by Gedinnian or Helderbergian time.