Campanium

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system series step ≈ age ( mya )
higher higher higher younger
chalk Upper Chalk Maastrichtium 66
⬍
72
Campanium 72
⬍
83.6
Santonium 83.6
⬍
86.3
Coniacium 86.3
⬍
89.7
Turonium 89.7
⬍
93.9
Cenomanium 93.9
⬍
100.5
Lower Cretaceous Albium 100.5
⬍
112.9
Aptium 112.9
⬍
126.3
Barremium 126.3
⬍
130.7
Skin rivium 130.7
⬍
133.9
Valanginium 133.9
⬍
139.3
Berriasium 139.3
⬍
145
deeper deeper deeper older

The Campanium (in German often shortened to Campan ) is a chronostratigraphic level of the Upper Cretaceous in the history of the earth . It began geochronologically about 83.6 million years ago and lasted until about 72 million years ago. The Campanium follows the Santonium and is replaced by the Maastrichtium .

Naming and history

Henri Coquand introduced the stage and the name in scientific literature in 1857, using "La Grande Champagne", a ridge near Aubeterre-sur-Dronne in the Charente department in France , as a type locality . Its former type locality has now turned out to be Maastrichtium .

Definition and GSSP

The lower limit is defined by the extinction of the sea ​​lily species Marsupites testudinarius , the upper limit by the first appearance of the ammonite species Pachydiscus neubergicus . A GSSP (global type locality and type profile) has not yet been finally ratified.

Breakdown

The campanium can be divided into the lower, middle and upper campaniums.

In the Tethys area, six ammonite zones are currently excreted in the Campanium (from young to old):

Fauna development

In the Campanium there was a great leap in the biodiversity of the dinosaurs . From the four genera found at the beginning of the campanium in North America, for example, the number of different dinosaur genera on this continent rose to 48 by the end of the campanium. In analogy to the Cambrian explosion of animal species in the Cambrian, one speaks of the "Campanian explosion" of biodiversity the dinosaur. However, it has not yet been clearly established to what extent the assumption of such a radiation can be traced back to the location of the finds, that is, that either less fossil evidence of dinosaurs exists from the early Campanium or that these have not yet been found. In any case, the campanium, with its hot climate that is spread over almost the entire globe and the vast shallow seas, provided an excellent ecological basis for the spread of dinosaurs and other animals. What is certain is that during the subsequent age, the Maastrichtian, the number of species of dinosaurs decreased by at least 30% until they became extinct in a relatively short period of time at the end of the Cretaceous Period.

literature

  • Felix Gradstein, Jim Ogg, Jim & Alan Smith: A Geologic timescale. Cambridge University Press 2004 ISBN 978-0-521-78673-7
  • Hans Murawski & Wilhelm Meyer: Geological dictionary . 10., rework. u. exp. Ed., 278 p., Enke Verlag, Stuttgart 1998 ISBN 3-432-84100-0 .
  • Weishampel, DB, Barrett, PM, Coria, RA, Le Loeuff, J., Xu, X., Zhao, X., Sahni, A., Gomani, EMP, and Noto, CR: Dinosaur distribution. In: DB Weishampel et al. (Ed.): The Dinosauria . 2nd Ed., Berkeley, University of California Press, 2004, pp. 517-606.

Web links