Famennian

The Famennian (usually called in the German language only Famennian ) is in Earth's history the top chronostratigraphic stage of the Late Devonian ( Devonian). The stage took geochronological from about 372.2 million to about 358.9 million years. The Famennian heads the Frasnian; it is followed by the Tournaisian, the lowest level of the Carboniferous.

Naming and history

The Famennian is named after the region Famennian in eastern Belgium. Stage and name were proposed in 1855 by André Dumont and introduced into the scientific literature.

Definition and GSSP

The base of the Famennian is directly above the Kellwasser horizon, a larger Aussterbeevent in the Upper Devonian. The end of the stage is also the Devonian - Carboniferous boundary, which is defined by the onset of conodont species Siphonodella sulcata. The reference profile ( GSSP = Global Stratotype Section and Point) is located in the upper Coumiac quarry near Cessenon, Hérault, Montagne Noire, France.

Subdivision

The Famennian is divided into eight conodont biozones:

  • Siphonodella praesulcata zone
  • Palmatolepis expansa Zone
  • Palmatolepis postera zone
  • Palmatolepis trachytera zone
  • Palmatolepis marginifera zone
  • Palmatolepis rhomboidea zone
  • Palmatolepis crepida zone
  • Palmatolepis triangularis Zone
Mya (unit) Givetian History of the Earth Famenne Cessenon-sur-Orb
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