Givetian

Summary

The Givetian is one of two faunal stages in the Middle Devonian Period. It lasted from 387.7 million years ago to 382.7 million years ago. It was preceded by the Eifelian Stage and followed by the Frasnian Stage. It is named after the town of Givet in France. The oldest forests occurred during the late Givetian.[7] The lower GSSP is located at Jebel Mech Irdane, Tafilalt, Morocco.

Givetian
387.7 ± 0.8 – 382.7 ± 1.6 Ma
Chronology
Etymology
Name formalityFormal
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 conodont Polygnathus hemiansatus
Lower boundary GSSPJebel Mech Irdane, Tafilalt, Morocco
31°14′15″N 4°21′15″W / 31.2374°N 4.3541°W / 31.2374; -4.3541
Lower GSSP ratified1994[5]
Upper boundary definitionFAD of the conodont Ancyrodella rotundiloba
Upper boundary GSSPCol du Puech de la Suque, Montagne Noire, France
43°30′12″N 3°05′12″E / 43.5032°N 3.0868°E / 43.5032; 3.0868
Upper GSSP ratified1986[6]

Name and definition edit

The Givetian Stage was proposed in 1879 by French geologist Jules Gosselet and was accepted for the higher stage of the Middle Devonian by the Subcommission on Devonian Stratigraphy in 1981.[8]

References edit

  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. 168 (4). London: Geological Society: 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. ^ Walliser, O.; Bultynck, P.; Weddige, K.; Becker, R.; House, M. (September 1995). "Definition of the Eifelian-Givetian Stage boundary". Episodes. 18 (3): 107–115. doi:10.18814/epiiugs/1995/v18i3/002. Retrieved 19 December 2020.
  6. ^ Klapper, Gilbert; Feist, Raimund; House, Michael (June 1987). "Decision on the Boundary Stratotype for the Middle/Upper Devonian Series Boundary". Episodes. 10 (2): 97–101. doi:10.18814/epiiugs/1987/v10i2/004. Retrieved 19 December 2020.
  7. ^ Becker, R.T.; Gradstein, F.M.; Hammer, O. (2012). "Chapter 22 - The Devonian Period". In Gradstein, F.M.; Ogg, J.G.; Schmitz, M.D.; Ogg, G.M. (eds.). The Geologic Timescale 2012. Elsevier. p. 578. doi:10.1016/b978-0-444-59425-9.00022-6. ISBN 978-0-444-59425-9.
  8. ^ Préat, Alain; Bultynck, Pierre (2006). "Givetian" (PDF). Geologica Belgica. 9 (1–2): 9–18. Retrieved 12 March 2013.

31°14′15″N 4°21′15″W / 31.2375°N 4.3542°W / 31.2375; -4.3542

Further reading edit