Sandbian

Key events in the Ordovician
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Key events of the Ordovician Period.
ICS approved stages.

Axis scale: millions of years ago.[2]

The Sandbian is the first stage of the Upper Ordovician. It follows the Darriwilian and is succeeded by the Katian. Its lower boundary is defined as the first appearance datum of the graptolite species Nemagraptus gracilis around 458.4 million years ago. The Sandbian lasted for about 5.4 million years until the beginning of the Katian around 453 million years ago.[3]

Naming

The name Sandbian is derived from the village Södra Sandby (Lund Municipality, Skåne County, Sweden). The name was proposed in 2006.[4]

GSSP

The GSSP of the Sandbian is the Fågelsång section (55°42′49″N 13°19′32″E / 55.7137°N 13.3255°E / 55.7137; 13.3255) at Sularp Brook, east of Lund (Skåne, Sweden). It is an outcrop of shale and mudstone. The lower boundary of the Sandbian is defined as the first appearance datum of graptolite species Nemagraptus gracilis in that section.[5]

References

  1. Wellman, C.H.; Gray, J. (2000). "The microfossil record of early land plants". Phil. Trans. R. Soc. B. 355 (1398): 717732. doi:10.1098/rstb.2000.0612. PMC 1692785Freely accessible. PMID 10905606.
  2. Gradstein, F. M., ed. (2012). The Geologic Time Scale 2012. Elsevier Science Ltd. p. 504. ISBN 978-0444594259.
  3. "GSSP Table - Paleozoic Era". Geologic Timescale Foundation. Retrieved 2 December 2012.
  4. Bergström, Stig; Finney, Stanley; Xu, Chen; Goldman, Daniel; Leslie, Stephen (31 August 2006). "Three new Ordovician global stage names". Lethaia. 39 (3): 287–288. doi:10.1080/00241160600847439.
  5. Bergström, Stig M.; S. C. Finney; Chen Xu; Christian Pålsson; Wang Zhi-hao; Yngve Grahn (2000). "A proposed global boundary stratotype for the base of the Upper Series of the Ordovician System: The Fågelsång section, Scania, southern Sweden" (PDF). Episodes. 23 (2): 102–109. Retrieved 20 September 2012.
Phanerozoic Eon
Paleozoic Era Mesozoic Era Cenozoic Era
Cambrian Ordovician Silurian Devonian Carboniferous Permian Triassic Jurassic Cretaceous Paleogene Neogene 4ry


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