Viséan

Name and definitions

The Viséan Stage was introduced by Belgian geologist André Dumont in 1832. Dumont named this stage after the city of Visé in Belgium's Liège Province. Before being used as an international stage, the Viséan Stage was part of the (West) European regional geologic time scale, in which it followed the Tournaisian Stage and is followed by the Namurian Stage. In the North American regional scale, the Viséan Stage correlates with the upper Osagean, the Meramecian and lower Chesterian stages. In the Chinese regional time scale, it correlates with the lower and middle Tatangian series.

The base of the Viséan Stage is at the first appearance of the fusulinid species Eoparastaffella simplex (morphotype 1/morphotype 2). The type locality for the stage base used to be in a road section below the castle of Dinant in Belgium, but this type locality proved to be insufficient for the purpose of stratigraphic correlation. A GSSP has been proposed in the Luzhai Formation near Penchong in the Chinese province of Guanxi. The top (the base of the Serpukhovian and Namurian) is laid at the first appearance of the conodont Lochriea ziegleri, or at the base of the biozone of goniatite Cravenoceras leion.