The Thanetian is, in the ICS Geologic timescale, the latest age or uppermost stratigraphic stage of the Paleocene Epoch or Series.
[6] Fossils of the unicellular planktonic marine coccolithophore Areoligeria gippingensis make their first appearance at the base of the Thanetian, and help define its lowest stratigraphic boundary.
The top of the Thanetian Stage (the base of the Ypresian) is defined at a strong negative anomaly in δ13C values at the global thermal maximum at the Paleocene-Eocene boundary.
It overlaps the obsolete regional stages Landenian and Heersian of Belgium.
In the lagerstätte, leaves, entire flowers and seeds are minutely preserved.