Tournaisian (English, name)
expansion: Tournaisian
Senses:
topics: geography
geology
natural-sciences
glosses: In the ICS geologic timescale, the lowest stage or oldest age of the Mississippian, the oldest subsystem of the Carboniferous. It lasted from 358.9 Ma to 346.7 Ma and was preceded by the Famennian and followed by the Viséan.
Forms: