Viséan
Encyclopedia
The Visean, Viséan or Visian is an age in the ICS
geologic timescale or a stage in the stratigraphic column
. It is the second stage of the Mississippian, the lower subsystem of the Carboniferous
. The Visean lasted from 345.3 ± 2.1 to 328.3 ± 1.6 Ma. It follows the Tournaisian
age/stage and is followed by the Serpukhovian
age/stage.
geologist André Dumont
in 1832. Dumont called this stage after the city of Visé
in the Belgian province of Liège. Before being used as an international stage, the Visean 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 Visean 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 Visean 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
.
In British stratigraphy, the Visean is subdivided into five substages. These are from bottom to top: Chadian (the lower part of this substage falls in the Tournaisian), Arundian, Holkerian, Asbian and Brigantian.
International Commission on Stratigraphy
The International Commission on Stratigraphy , sometimes referred to by the unofficial "International Stratigraphic Commission" is a daughter or major subcommittee grade scientific daughter organization that concerns itself with stratigraphy, geological, and geochronological matters on a global...
geologic timescale or a stage in the stratigraphic column
Stratigraphic column
A stratigraphic column is a representation used in geology and its subfield of stratigraphy to describe the vertical location of rock units in a particular area....
. It is the second stage of the Mississippian, the lower subsystem of the Carboniferous
Carboniferous
The Carboniferous is a geologic period and system that extends from the end of the Devonian Period, about 359.2 ± 2.5 Mya , to the beginning of the Permian Period, about 299.0 ± 0.8 Mya . The name is derived from the Latin word for coal, carbo. Carboniferous means "coal-bearing"...
. The Visean lasted from 345.3 ± 2.1 to 328.3 ± 1.6 Ma. It follows the Tournaisian
Tournaisian
The Tournaisian is in the ICS geologic timescale the lowest stage or oldest age of the Mississippian, the oldest subsystem of the Carboniferous. The Tournaisian age lasted from 359.2 ± 2.5 Ma to 345.3 ± 2.1 Ma...
age/stage and is followed by the Serpukhovian
Serpukhovian
The Serpukhovian is in the ICS geologic timescale the uppermost stage or youngest age of the Mississippian, the lower subsystem of the Carboniferous. The Serpukhovian age lasted from 328.3 Ma tot 318.1 Ma...
age/stage.
Name and definitions
The Visean stage was introduced by BelgianBelgium
Belgium , officially the Kingdom of Belgium, is a federal state in Western Europe. It is a founding member of the European Union and hosts the EU's headquarters, and those of several other major international organisations such as NATO.Belgium is also a member of, or affiliated to, many...
geologist André Dumont
André Dumont
André Hubert Dumont was a Belgian geologist.Dumont was born in Liège. His first work was a masterly Mémoire on the geology of the province of Liège published in 1832. A few years later he became a professor of mineralogy and geology and afterwards Rector of the University of Liège...
in 1832. Dumont called this stage after the city of Visé
Visé
Visé is a Walloon municipality and city of Belgium, where it is located on the river Meuse, in the province of Liège.The municipality consists of the former municipalities of Visé, Lanaye, Lixhe, Richelle, Argenteau and Cheratte....
in the Belgian province of Liège. Before being used as an international stage, the Visean stage was part of the (West) European regional geologic time scale, in which it followed the Tournaisian stage and is followed by the Namurian
Namurian
The Namurian is a stage in the regional stratigraphy of northwest Europe with an age between roughly 326 and 313 Ma . It is a subdivision of the Carboniferous system or period and the regional Silesian series. The Namurian is named for the Belgian city and province of Namur where strata of this age...
stage. In the North American regional scale, the Visean 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
Series (stratigraphy)
Series are subdivisions of rock layers made based on the age of the rock and corresponding to the dating system unit called an epoch, both being formally defined international conventions of the geological timescale. A series is therefore a sequence of rock depositions defining a...
.
The base of the Visean stage is at the first appearance of the fusulinid
Fusulinid
The Fusulinida is an extinct order within the Foraminifera in which the tests are composed of tightly packed, secreted microgranular calcite. In advanced forms the test wall is differentiated into two or more layers...
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
Dinant
Dinant is a Walloon city and municipality located on the River Meuse in the Belgian province of Namur, Belgium. The Dinant municipality includes the old communes of Anseremme, Bouvignes-sur-Meuse, Dréhance, Falmagne, Falmignoul, Foy-Notre-Dame, Furfooz, Lisogne, Sorinnes, and Thynes.-Origins to...
in Belgium, but this type locality
Type locality (geology)
Type locality , also called type area or type locale, is the where a particular rock type, stratigraphic unit, fossil or mineral species is first identified....
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
Guanxi
Guanxi describes the basic dynamic in personalized networks of influence, and is a central idea in Chinese society. In Western media, the pinyin romanization of this Chinese word is becoming more widely used instead of the two common translations—"connections" and "relationships"—as neither of...
. The top (the base of the Serpukhovian and Namurian) is laid at the first appearance of the conodont
Conodont
Conodonts are extinct chordates resembling eels, classified in the class Conodonta. For many years, they were known only from tooth-like microfossils now called conodont elements, found in isolation. Knowledge about soft tissues remains relatively sparse to this day...
Lochriea ziegleri, or at the base of the biozone
Biozone
Biostratigraphic units or Biozones are intervals of geological strata that are defined on the basis of their characteristic fossil taxa....
of goniatite
Goniatite
Goniatites are extinct ammonoids, shelled cephalopods related to squid, octopus, and belemnites, that form the order Goniatitida. The Gonatitida originated from within the more primitive anarcestine ammonoids in the Middle Devonian some 390 million years ago...
Cravenoceras leion
Cravenoceras
Cravevoceras is an Upper Paleozoic ammonite in the gonititid family Cravenoceratidae, probably derived from Pachylyroceras and contemporaty with other cravenoceratid genera like Caenolyroceras, Tympanoceras and later Alaoceras and Lyrogoniatites...
.
Biostratigraphy
The Visean contains four conodont biozones:- Lochriea nodosa Zone
- Lochriea mononodosa Zone
- Gnathodus bilineatus Zone
- Gnathodus texanus Zone
In British stratigraphy, the Visean is subdivided into five substages. These are from bottom to top: Chadian (the lower part of this substage falls in the Tournaisian), Arundian, Holkerian, Asbian and Brigantian.
Literature
; 2003: A proposed Global Stratotype Section and Point for the base of the Visean Stage (Carboniferous): the Pengchong section, Guangxi, South China, Episodes 26(2), pp 105–115.; 1832: Mémoire sur la constitution géologique de la province de Liège, Mémoires couronnés par l'Académie Royale des Sciences et Belles-Lettres de Bruxelles 8(3), VII. ; 2004: A Geologic Time Scale 2004, Cambridge University Press.; 2006: The Carboniferous system, use of the new official names for the subsystems, series and stages, Geologica Acta 4(3), pp 403-407.; 2006: Global time scale and regional stratigraphic reference scales of Central and West Europe, East Europe, Tethys, South China, and North America as used in the Devonian–Carboniferous–Permian Correlation Chart 2003 (DCP 2003), Palaeogeography, Palaeoclimatology, Palaeoecology 240(1-2): pp 318-372.; 2005: Late Visean/early Serpukhovian conodont succession from the Triollo section, Palencia (Cantabrian Mountains, Spain), Scr. Geol. 129, pp 13-89.External links
- Upper and lower time scales for the Carboniferous at the website of the Norwegian network of offshore records of geology and stratigraphy.
- Visean, Geowhen Database
- The Viséan age, www.palaeos.com