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The Upper Jurassic-Lower Cretaceous sedimentary rocks in the Eastern Barents Sea Basin are up to 2 km thick and represent one of the least studied Arctic intervals. Here, for the first time, we present a detailed analysis of 43,000 km of 2D seismic profiles, as well as well-log and core data from 24 offshore wells with the aim to create a comprehensive sequence stratigraphic framework that can be integrated with the rest of the basin. Results show that (1) seven third-order sequences and five types of clinoforms can be identified based on integrated seismic and well data. The age of each sequence was established based on published biostratigraphic investigations along with new dinocyst interpretations included in this study; (2) the deep marine basin was gradually filled with sediments coming from north, east and south as a response to HALIP, Canada Basin opening and Cimmerian uplift of Novaya Zemlya, and was preserved only in the southwestern part of the Barents Sea Basin at the end of Early Cretaceous and (3) both Eastern Barents Sea and West Siberia Basin share similarities in sedimentary environments and tectonic setting, though the spatial distribution of clastic reservoirs in Upper Jurassic and Lower Cretaceous mega-sequence heavily depends on the source areas that require more provenance focused research. The results presented here can be used in further regional exploration in the area and to better understand the geodynamic evolution of the Greater Barents Sea Basin. [ABSTRACT FROM AUTHOR]

Triassic strata in the Greater Barents Sea Basin are important records of geodynamic activity in the surrounding catchments and sediment transport in the Arctic basins. This study is the first attempt to investigate the evolution of these source areas through time. Our analysis of sediment budgets from subsurface data in the Greater Barents Sea Basin and application of the BQART approach to estimate catchment properties shows that (1) during the Lower Triassic, sediment supply was at its peak in the basin and comparable to that of the biggest modern-day river systems, which are supplied by tectonically active orogens; (2) the Middle Triassic sediment load was significantly lower but still comparable to that of the top 10 largest modern rivers; (3) during the Upper Triassic, sediment load increased again in the Carnian; and (4) there is a large mismatch (70%) between the modeled and estimated sediment load of the Carnian. These results are consistent with the Triassic Greater Barents Sea Basin succession being deposited under the influence of the largest volcanic event ever at the Permian- Triassic boundary (Siberian Traps) and concurrent with the climatic changes of the Carnian Pluvial Event and the final stages of the Northern Ural orogeny. They also provide a better understanding of geodynamic impacts on sedimentary systems and improve our knowledge of continental-scale sediment transport. Finally, the study demonstrates bypass of sediment from the Ural Mountains and West Siberia into the adjacent Arctic Sverdrup, Chukotka, and Alaska Basins in Late Carnian and Late Norian time. [ABSTRACT FROM AUTHOR]

One of the largest delta plains in Earth's history existed in the Barents Sea during the Triassic. It is known that the clastic sediments that filled this basin were sourced from the Uralide Orgeny. Recent studies indicate that the source-areas are more diverse, with one source located in the northern Uralides/Novaya Zemlya, one in Northern Fennoscandia and another in Northern Greenland. Contribution from these sources varied through time. The subsidence rates were very high in the Barents Sea during the Triassic. Sedimentation rates were particularly high during the Induan, when the largest clastic wedges prograded into the basin. Sedimentation rates were lower during the late Early Triassic and Middle Triassic, when no particular tectonic events took place in the source areas. During the Carnian, sediment supply rates increase and deltas prograded to Svalbard and likely beyond Svalbard. Sediment supply rates during the Late Triassic were not as high as during the Early Triassic, but operated over a longer time and thus has a thickness at the same scale as the Induan succession. Within the Barents Sea, more than ten third order sequences were mapped delineated by four second order sequences. Regional distribution of sequences varied through time, with different thicknesses and sediment pathways. Our results show variation in sedimentation rates, clinoform geometries and shelf-edge- and shoreline-trajectories. This variation was caused by different forcing factors operating in the source and sink. Information about the large-scale depositional system can potentially increase our understanding of reservoir nature and distribution as well as source rock potential in the basin. [ABSTRACT FROM AUTHOR]