Abstract This paper focuses on the Cenozoic evolution of the northern North Sea and surrounding areas, with emphasis on sediment distribution, composition and provenance, as well as on timing, amplitude and wavelength of differential vertical movements. Quantitative information about palaeo-water depth and tectonic vertical movements has been integrated with a seismic stratigraphic framework to better constrain the Cenozoic evolution. The data and modelling results support a probable tectonic control on sediment supply and on the formation of regional unconformities. The sedimentary architecture and breaks are related to tectonic uplift of surrounding clastic source areas, thus the offshore sedimentary record provides the best age constraints on Cenozoic exhumation of the adjacent onshore areas. Tectonic subsidence accelerated in Paleocene time throughout the basin, with uplifted areas to the east and west sourcing prograding wedges, which resulted in large depocentres close to the basin margins. Subsidence rates outpaced sedimentation rates along the basin axis, and water depths in excess of 600 m are indicated. In Eocene times progradation from the East Shetland Platform was dominant and major depocentres were constructed in the Viking Graben area, with deep water along the basin axis. At the Eocene-Oligocene transition, southern Norway and the eastern basin flank became uplifted. The uplift, in combination with prograding units from both the east and west, gave rise to a shallow threshold in the northern North Sea, separating deeper waters to the south and north. The uplift and shallowing continued into Miocene time when a widespread hiatus formed in the northern North Sea, as indicated by biostratigraphic data. The Pliocene basin configuration was dominated by outbuilding of thick clastic wedges from the east and south. Considerable late Cenozoic uplift of the eastern basin flank is documented by the strong angular relationship and tilting of the complete Tertiary package below the Pleistocene unconformity. Cenozoic exhumation is documented on both sides of the North Sea, but the timing is not well constrained. Two major uplift phases in early Paleogene and late Neogene times are related to rifting, magmatism and break-up in the NE Atlantic and isostatic response to glacial erosion, respectively. Additional uplift events may be related to mantle processes and the episodic behaviour of the Iceland plume.

Abstract The Cenozoic depositional history along a regional E-W profile across the northern North Sea has been simulated using a forward process-based simulation program of dynamic-slope type. It involves a depth-dependent, dual-lithology diffusion equation that handles transport, erosion and deposition of sediments. The data used in the simulation were derived from a seismic line calibrated against wells, and from the regional literature concerning the northern North Sea. The most important of the factors used are: the initial basin form (Paleocene bathymetry), tectonic subsidence, isostatic variables, sediment supply (sand-shale), sediment compaction (porosity-depth relationships for sand-shale) and eustatic sea-level changes. The interaction between the data values extracted from the literature could not reproduce a cross-section similar to the observed cross-section from seismic data. Therefore, the subsidence pattern and the initial basin form were reconsidered. The resulting model gave an anomalous Cenozoic subsidence pattern, different from the expected post-rift thermal subsidence, with deviations corresponding to Paleocene and Late Miocene-Pliocene times. The model-derived Paleocene subsidence might have been overestimated by using an over-shallow palaeobathymetric value, although a deepening of the basin is also indicated by biostratigraphic data. The pronounced Neogene subsidence created accommodation space for a thick Pliocene sequence, derived from the uplifted eastern source area.