Devonian

Frae Wikipedia
Jump to navigation Jump to search
Devonian Period
419.2–358.9 million years aby
Mean atmospheric O
2
content ower period duration
c. 15 vol %
(75 % o modren level)
Mean atmospheric CO
2
content ower period duration
c. 2200 ppm
(8 times pre-industrial level)
Mean surface temperatur ower period duration c. 20 °C
(6 °C abuin modren level)
Sea level (abuin present day) Relatively steady aroond 189m, gradually fawin tae 120m throu period[1]
Events of the Devonian Period
-420 —
-415 —
-410 —
-405 —
-400 —
-395 —
-390 —
-385 —
-380 —
-375 —
-370 —
-365 —
-360 —
-355 —
Widespread[4]
shrubs & trees
S. America
glaciation begins
Key events o the Devonian Period.
Axis scale: millions o years ago.

The Devonian is a geologic period an seestem o the Paleozoic, spannin 60 million years frae the end o the Silurian, 419.2 million years ago (Mya), tae the beginnin o the Carboniferous, 358.9 Mya.[5]

References[eedit | eedit soorce]

  1. Haq, B. U.; Schutter, SR (2008). "A Chronology of Paleozoic Sea-Level Changes". Science. 322 (5898): 64–68. Bibcode:2008Sci...322...64H. doi:10.1126/science.1161648. PMID 18832639. 
  2. 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. 
  3. 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. 
  4. 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. 
  5. Gradstein, Felix M.; Ogg, J. G.; Smith, A. G. (2004). A Geologic Time Scale 2004. Cambridge: Cambridge University Press. ISBN 0521786738.