Toarcian (184.2 +/-0.3 Ma)

Rappresentazione e statuto

Index

toa

Colore CMYK

40 / 5 / 0 / 0

Colore RGB

R: 153 G: 206 B: 227

Rango

Piano cronostratigrafico

Uso

Unità in uso.

Status

termine formale valido

Discussione del statuto

Nomenclatura

Deutsch

Toarcien (CH) (DE/AT: Toarcium / Toarc)

Français

Toarcien

Italiano

Toarciano

English

Toarcian (184.2 +/-0.3 Ma)

Origine del nome

Named after the town of Thouars (Deux-Sèvres, France), south of Saumur. The protected stratotype lies in an old quarry. Its GSSP is located at Peniche (Portugal).

Varianti storiche

Lias supérieur (d'Orbigny 1842), Toarcien (d'Orbigny 1849), Thouarsien (Mayer-Eymar 1864, Mouterde 1956), 12e Etage = Toarcien (Greppin 1866)

Nota sul nome

Latin: Toarcium

Gerarchia e successione

Unità di rango inferiore

• Late Toarcian
• Middle Toarcian
• Early Toarcian

Unità sovrastante

• Aalenian (174.1 +/-1.0 Ma)

Limite superiore

Top lies just below the first appearance of the ammonite genus Leioceras.

Limite inferiore

Base defined by the first appearance of Eodactylites mirabile (Tethyan Realm), or alternatively by the mass appearance of other dactylioceratids together with Paltarpites paltus.

Età

Geomorfologia

• Toarciano

Età alla base

• Toarciano

Geografia

Regione-tipo

Deux-Sèvres (Paris Basin, France)

Sezione-tipo

• Carrière de Vrines (Deux-Sèvres), près de Thouars
  Caratteristiche del sito
  • typische Fazies
  Agibilità del sito
  • geschützter Geotop
  Nota
  • <p>Proposed by d'Orbigny (1849) and further studied by Eudes-Deslongchamps and Welsch. Detailed biostratigraphy by Gabilly (1976), who pointed out the condensed nature (7 m altogether) of the section and the incompleteness of the record at the base.</p>

Sezione di riferimento

• Anse Saint-Nicolas, Jard-sur-Mer (Vendée, France)
  Caratteristiche del sito
  • Untergrenze
  Nota
  • Complementary profile proposed by Gabilly (1976) for the base of the Toarcian stage.

Referenze

Definizione

d'Orbigny A. (1846) : Foraminifères fossiles du bassin tertiaire de Vienne (Autriche). Gide, Paris

Ce nom dérive de la ville de Thouars (Toarcium) (Deux-Sèvres), où l'on ne trouve que cet étage sur les roches aszoïques; où il a le plus beau développement en France et peut être regardé comme point type, point étalon. C'est la zone du Lima gigantea et de l'Ammonites bifrons.

Materiale e vario