Stratigraphic Definition
The Campanian was introduced in scientific literature by Henri Coquand in 1857. It is named after the French village of Champagne in the département Charente-Maritime. The original type locality was an outcrop near the village of Aubeterre-sur-Dronne in the same region. Due to changes of the stratigraphic definitions, this section is now part of the Maastrichtian stage.
The base of the Campanian stage is laid at the extinction of crinoid species Marsupites testudinarius. A GSSP had not yet been ratified in 2009. One possible candidate is in a section near a dam at Waxahachie, Texas.
The top of the Campanian is defined as the place in the stratigraphic column were the ammonite Pachydiscus neubergicus first appears.
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