Fig. 1

Contrasting evidence for the existence of seaways across the Barents Shelf near the Eocene–Oligocene transition (EOT). a Palaeogeography for the late Eocene as portrayed by Baatsen et al.³⁶. b Modern bathymetry of the Barents shelf. The seaways present across the Barents shelf in the palaeogeography of Baatsen et al.³⁶ coincide with the deepened glacial troughs that were formed during Quaternary glaciations. c Re-drawn depositional environments on the Barents shelf in the late Eocene, published in Smelror et al.⁴⁴, p. 123. The gradual closure of seaways between Svalbard and Greenland and across the Barents Sea during the Eocene is consistent with far-field geologic evidence^30,39 and recent tectonic reconstructions of the Northwestern and Southwestern margins of the Barents Sea (between Svalbard and mainland Norway) by Lasabuda et al.^45,46. See Supplementary Fig. 1 for further details