Reasons for a name
The Thanetian was established by Swiss geologist Eugène Renevier (1874) to include the Thanet Sands and the overlying Woolwich and Reading Series. The Thanet sands are the oldest Cenozoic deposit of the London Basin, which was first identified in the area of Kent (southern England) known as the Isle of Thanet (no longer a island, since the channel that separated it from England and the Kent mainland is now flat marshland). The base of the Thanetian stage is laid at the base of magnetic chronozone C26n. The references profile (Global Boundary Stratotype Section and Point) is in the Zumaia section (43° 18’N, 2° 16’W) at the beach of Itzurun, Pais Vasco, northern Spain. 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 ?13C values at the global thermal maximum at the Paleocene-Eocene boundary. The Thanetian stage is coeval the lower Neustrian European land mammal age (it spans the Mammal Paleogene zone 6 and part of zones 1 through 5), the upper Tiffanian and Clarkforkian North American land mammal ages, the Riochican and part of the Itaboraian South American land mammal ages and the upper Nongshanian and Gashatan Asian land mammal ages. The Thanetian is contemporary with the middle Wangerripian regional stage of Australia and the upper Ynezian regional stage of California. It overlaps the obsolete regional stages Landenian and Heersian of Belgium.