Gelasian

The Gelasian is a stage whose belonging to either the Pliocene or the Pleistocene Epochs is currently discussed. It spans the time between 2.588 ± 0.005 Ma (million years ago) and 1.806 ± 0.005 Ma. . The Gelasian correlates with the period covering the deposition of the Red Crag of Butley and Newbourn and the Norwich and Weybourn Crags, all from East Anglia (England). Likewise the Gelasian is an equivalent of the Praetiglian and Tiglian stages as defined in the Netherlands.

The International Union for Quaternary Research (INQUA) has proposed that the Gelasian be moved from the Pliocene to the Pleistocene in order that the geologic time scale be more consistent with the key changes in Earth's climate, oceans, and biota that occurred then (2.588 Ma) and corresponding to the Gauss-Matuyama magnetostratigraphic boundary.