A comprehensive dataset is collated in a study on sediment transport, timing and basin physiography during the Early Cretaceous Period in the Boreal Basin (Barents Sea), one of the world’s largest and longest active epicontinental basins. Long-wavelength tectonic tilt related to the Early Cretaceous High Arctic Large Igneous Province (HALIP) set up a fluvial system that developed from a sediment source area in the NW, which flowed SE across the Svalbard archipelago, terminating in a low-accommodation shallow sea within the Bjarmeland Platform area of the present-day Barents Sea. The basin deepened to the SE with a ramp-like basin floor with gentle dip. Seismic data show sedimentary lobes with internal clinoform geometry that advanced from the NW. These lobes interfingered with, and were overlain by, another younger depositional system with similar lobes sourced from the NE. The integrated data allow mapping of architectural patterns that provide information on basin physiography and control factors on source-to-sink transport and depositional patterns within the giant epicontinental basin. The results highlight how low-gradient, low-accommodation sediment transport and deposition has taken place along proximal to distal profiles for several hundred kilometres, in response to subtle changes in base level and by intra-basinal highs and troughs. Long-distance correlation along depositional dip is therefore possible, but should be treated with caution to avoid misidentification of timelines for diachronous surfaces.

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Regional Early Cretaceous uplift of the northern Barents Sea associated with the High Arctic Large Igneous Province (HALIP) caused the development of the fluvial to open-marine depositional system, terminating in the southwestern Barents Sea. This study has established a new temporal and spatial evolution of the Lower Cretaceous deposits in the Hoop area, in particular the location and age of the intrashelf platform lobe front and subsequent block-faulting. A composite high-resolution 3D and 2.5D P-Cable and conventional 3D seismic dataset image the strata and cross-cutting faults in the Hoop area. The P-Cable data typically have a resolution of 3-7 m in the shallow subsurface, up to four times better than the conventional seismic data, contributing to a new and better mapping hence understanding of the Lower Cretaceous strata and faults. Seismic horizon and facies mapping reveal large-scale clinoforms, with present-day heights of 150-200 m and dips of 0.65-1.13°. The highresolution data furthermore display complex stratigraphic and structural features, such as small-scale clinoforms and numerous faults. The shelf platform succession is block-faulted, and the main Early Cretaceous fault activity thus postdates the arrival of the delta and platform sediments from the northwest. Detailed seismo-stratigraphic ties to the 7324/2-1 (Apollo) and 7325/1-1 (Atlantis) wells, and ties to the adjacent Fingerdjupet Subbasin, document a Barremian age for the shelf platform deposits and an Aptian?-early Albian age for the main faulting event. The faulting was likely initiated in the Aptian, but a hiatus or condensed section above the Barremian strata makes it difficult to constrain the onset of deformation in the Hoop area.