At the edge of a new ocean: post-volcanic evolution of the Palaeogene Kap Dalton Group, East Greenland

Following the extensive flood basalt volcanism that accompanied the onset of seafloor spreading and arrival of the proto-Icelandic hotspot in the North Atlantic region, marine sedimentation resumed during the early Middle Eocene. In East Greenland, post-basaltic sediments exposed at Kap Dalton and Savoia Halvø represent the scattered remains of a much more widespread, fluvial to shallow-marine succession. Deposition in the late Paleocene-Eocene was governed by a complex interplay between loading, thermal contraction of the oceanic crust, passage of the hotspot and eustatic sea-level changes. At Kap Dalton extrusion of Early Eocene, Chron C21r flood basalts was followed by subaerial erosion, creating an irregular relief dissected by fluvial channels. The area was transgressed during the early Middle Eocene and, during the Middle Eocene, a muddy, poorly oxygenated shelf was formed. The presence of clean quartz sandstones within the early post-basaltic succession indicates that areas with little or no basaltic cover became periodically exhumed. The depositional events documented in the Kap Dalton succession strengthen the possibility of Middle Eocene non-volcanic reservoir units being present in the offshore areas, lending support to the Eocene play in the northern North Atlantic region.