Albian
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 Planktonic Foraminifer Microhedbergella renilaevis
Lower boundary GSSPCol de Pré-Guittard section, Arnayon, Drôme, France
44°29′47″N 5°18′41″E / 44.4964°N 5.3114°E / 44.4964; 5.3114
Lower GSSP ratifiedApril 2016[2]
Upper boundary definitionFAD of the Planktonic Foraminifer Rotalipora globotruncanoides
Upper boundary GSSPMont Risoux, Hautes-Alpes, France
44°23′33″N 5°30′43″E / 44.3925°N 5.5119°E / 44.3925; 5.5119
Upper GSSP ratified2002[3]

The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous Epoch/Series. Its approximate time range is 113.0 ± 1.0 Ma to 100.5 ± 0.9 Ma (million years ago). The Albian is preceded by the Aptian and followed by the Cenomanian.[4]

Stratigraphic definitions

The Albian Stage was first proposed in 1842 by Alcide d'Orbigny. It was named after Alba, the Latin name for River Aube in France.

A Global Boundary Stratotype Section and Point (GSSP), ratified by the IUGS in 2016, defines the base of the Albian as the first occurrence of the planktonic foraminiferan Microhedbergella renilaevis at the Col de Pré-Guittard section, Arnayon, Drôme, France.[5]

The top of the Albian Stage (the base of the Cenomanian Stage and Upper Cretaceous Series) is defined as the place where the foram species Rotalipora globotruncanoides first appears in the stratigraphic column.[6]

The Albian is sometimes subdivided in Early/Lower, Middle and Late/Upper subages or substages. In western Europe, especially in the United Kingdom, a subdivision in two substages (Vraconian and Gaultian) is more often used.

Examples

Examples of Albian sedimentary rock are: the phosphorite beds of the Argonne and Bray areas in France; the Flammenmergel of northern Germany; the lignites of Utrillas in Spain; the Upper Nubian Sandstones, and the Fredericksburg beds of North America.[7]

References

Notes

  1. International Commission on Stratigraphy. "ICS - Chart/Time Scale". www.stratigraphy.org.
  2. Kennedy, J.W.; Gale, A.S.; Huber, B.T.; Petrizzo, M.R.; Bown, P.; Jenkyns, H.C. (2017). "The Global Boundary Stratotype Section and Point (GSSP) for the base of the Albian Stage, of the Cretaceous, the Col de Pré-Guittard section, Arnayon, Drôme, France" (PDF). Episodes. 40 (3): 177–188. doi:10.18814/epiiugs/2017/v40i3/017021.
  3. Kennedy, W.; Gale, A.; Lees, J.; Caron, M. (March 2004). "The Global Boundary Stratotype Section and Point (GSSP) for the base of the Cenomanian Stage, Mont Risou, Hautes-Alpes, France" (PDF). Episodes. 27: 21–32. doi:10.18814/epiiugs/2004/v27i1/003. Retrieved 13 December 2020.
  4. For a detailed geologic timescale, see Gradstein et al. (2004)
  5. Kennedy, J.W.; Gale, A.S.; Huber, B.T.; Petrizzo, M.R.; Bown, P.; Jenkyns, H.C. (2017). "The Global Boundary Stratotype Section and Point (GSSP) for the base of the Albian Stage, of the Cretaceous, the Col de Pré-Guittard section, Arnayon, Drôme, France" (PDF). Episodes. 40 (3): 177–188. doi:10.18814/epiiugs/2017/v40i3/017021.
  6. See Kennedy et al. (2004) for a description of the GSSP for the Cenomanian
  7. One or more of the preceding sentences incorporates text from a publication now in the public domain: Howe, John Allen (1911). "Albian". In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 1 (11th ed.). Cambridge University Press. p. 505.

Literature

  • Gradstein, F.M.; Ogg, J.G. & Smith, A.G.; 2004: A Geologic Time Scale 2004, Cambridge University Press.
  • Kennedy, W.J.; Gale, A.S.; Lees, J.A. & Caron, M.; 2004: The Global Boundary Stratotype Section and Point (GSSP) for the base of the Cenomanian Stage, Mont Risou, Hautes-Alpes, France, Episodes 27, pp. 21–32.
  • d'Orbigny, A.C.V.M.; 1842: Paléontologie française: Terrains crétacés, vol. ii. (in French)
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