Roadian

Roadian
273.01 ± 0.14 – 266.9 ± 0.4 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 Jinogondolella nanginkensis
Lower boundary GSSPStratotype Canyon, Guadalupe Mountains, Texas, USA
31°52′36″N 104°52′36″W / 31.8767°N 104.8768°W / 31.8767; -104.8768
Lower GSSP ratified2001[2]
Upper boundary definitionFAD of the Conodont Jinogondolella aserrata
Upper boundary GSSPGuadalupe Pass, Guadalupe Mountains, Texas, USA
31°51′57″N 104°49′58″W / 31.8658°N 104.8328°W / 31.8658; -104.8328
Upper GSSP ratified2001[2]

In the geologic timescale, the Roadian is an age or stage of the Permian. It is the earliest or lower of three subdivisions of the Guadalupian Epoch or Series. The Roadian lasted between 273.01 and 266.9 million years ago (Ma). It was preceded by the Kungurian and followed by the Wordian.[3]

  1. ^ "International Chronostratigraphic Chart" (PDF). International Commission on Stratigraphy. September 2023. Retrieved November 10, 2024.
  2. ^ a b "GSSP for Roadian Stage". International Commission on Stratigraphy. Retrieved 13 December 2020.
  3. ^ Gradstein, F.M.; Ogg, J.G. & Smith, A.G.; 2004: A Geologic Time Scale 2004, Cambridge University Press