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.

Lochkovian
419.2 ± 3.2 – 410.8 ± 2.8 Ma
Chronology
Etymology
Name formalityFormal
Name ratified1985[5]
Usage information
Celestial bodyEarth
Regional usageGlobal (ICS)
Time scale(s) usedICS Time Scale
Definition
Chronological unitAge
Stratigraphic unitStage
Time span formalityFormal
Lower boundary definitionFAD of the graptolite Monograptus uniformis
Lower boundary GSSPKlonk, Prague, Czech Republic
49°51′18″N 13°47′31″E / 49.8550°N 13.7920°E / 49.8550; 13.7920
GSSP ratified1972[6]
Upper boundary definitionFAD of the conodonts Eognathodus sulcatus and Latericriodus steinachensis Morph beta
Upper boundary GSSPVelká Chuchle quarry, Velká Chuchle, Prague, Czech Republic
50°00′53″N 14°22′21″E / 50.0147°N 14.3726°E / 50.0147; 14.3726
GSSP ratified1989[5]

In North America the Lochkovian Stage is represented by Gedinnian or Helderbergian time.

ReferencesEdit

  1. ^ Parry, S. F.; Noble, S. R.; Crowley, Q. G.; Wellman, C. H. (2011). "A high-precision U–Pb age constraint on the Rhynie Chert Konservat-Lagerstätte: time scale and other implications". Journal of the Geological Society. London: Geological Society. 168 (4): 863–872. doi:10.1144/0016-76492010-043.
  2. ^ Kaufmann, B.; Trapp, E.; Mezger, K. (2004). "The numerical age of the Upper Frasnian (Upper Devonian) Kellwasser horizons: A new U-Pb zircon date from Steinbruch Schmidt(Kellerwald, Germany)". The Journal of Geology. 112 (4): 495–501. Bibcode:2004JG....112..495K. doi:10.1086/421077.
  3. ^ Algeo, T. J. (1998). "Terrestrial-marine teleconnections in the Devonian: links between the evolution of land plants, weathering processes, and marine anoxic events". Philosophical Transactions of the Royal Society B: Biological Sciences. 353 (1365): 113–130. doi:10.1098/rstb.1998.0195.
  4. ^ "Chart/Time Scale". www.stratigraphy.org. International Commission on Stratigraphy.
  5. ^ a b Chlupac, Ivo; Oliver, William (June 1989). "Decision on the Lochkovian-Pragian Boundary Stratotype (Lower Devonian)" (PDF). Episodes. 12 (2): 109–114. Retrieved 18 December 2020.
  6. ^ Chlupáč, Ivo; Hladil, Jindrich (January 2000). "The global stratotype section and point of the Silurian-Devonian boundary". CFS Courier Forschungsinstitut Senckenberg. Retrieved 7 December 2020.
  7. ^ "Lochkovian Stage". Encyclopedia Britannica. Retrieved 2 October 2019.