Viséan

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 346.7 ± 0.4 to 330.9 ± 0.2 Ma. It follows the Tournaisian age/stage and is followed by the Serpukhovian age/stage.