Valanginian

The Valanginian ( in German often shortened to Valanginian ) is in Earth's history, a chronostratigraphic stage of the Lower Cretaceous. You geochronological covers the period from about 139.3 to about 133.9 million years. The Valanginian following the Berriasian and is detached from the Hauterivian.

Naming and history

The original type locality is in the Seyon Gorge near Valanginian in Switzerland; the stage is named after this place. The stage and the name were introduced by Édouard Desor 1853.

Definition and GSSP

The stage begins with the first appearance of Calpionelliden Type Calpionellites darderi and ends with the first appearance of the ammonite genus Acanthodiscus.

Subdivision

The Valanginian is divided in Tethysbereich in five ammonite biozones:

  • Criosarasinella furcillata
  • Neocomites peregrinus
  • Saynoceras verrucosum
  • Busnardoites campylotoxus
  • Tirnovella pertransiens

The Valanginian is further divided into the Lower School Lower Valanginian and Upper Valanginian. The first appearance of the ammonite Saynoceras verrucosum defines the beginning of the Upper Valanginiums, at the same time began the major transgression Va3 with.

Mya (unit) Danian Maastrichtian Campanian Santonian Albian Aptian Barremian History of the Earth
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