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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Two nested clinoform set types of different scales and steepness are mapped and analysed from high‐resolution seismic data. Restoration of post‐depositional faulting reveals a persistent pattern of small‐scale, high‐angle clinoforms contained within platform‐scale, low‐angle clinothems, showing a combined overall progradational depositional system. The large clinoforms lack a well‐defined platform edge, and show a gradual increase in dip from topset to foreset. A consistent recurring stratal pattern is evident from the architecture, and is considered a result of interplay between relative sea‐level change and autocyclic switching of sediment delivery focal points that brought sediment to the platform edge. This un‐interrupted succession records how intra‐shelf platforms prograde. Quantitative clinoform analysis may assist in determining the most influential depositional factors. Post‐depositional uplift and erosion requires restoration with re‐burial to maximum burial depth. Backstripping, decompaction and isostatic correction was performed assuming a range of lithologic compositions, as no wells test the lithology. Nearby wells penetrate strata basinward of the clinoforms, proving mudstone content above 50%, which in turn guide restoration values. Typical restored platform heights are 250–300 m, with correspondingly sized platform‐scale clinoform heights. Typical large‐scale clinoform foreset dip values are 1.3°–2.4°. Small‐scale clinothems are typically 100 m thick, with restored foreset dip angles at 4.4° ‐ > 10°. The results suggest that intrashelf platform growth occurs in pulses interrupted by draping of strata over its clinoform profile. The resultant architecture comprises small‐scale clinoforms nested within platform‐scale clinothems.

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