A regional net erosion map for the greater Barents Sea shows that the different areas in the Barents Sea region have been subject to different magnitudes of uplift and erosion. Net erosion values vary from 0 to more than 3000 m. The processes have important consequences for the petroleum systems. Reservoir quality, maturity of the source rocks and the migration of hydrocarbons are affected by the processes. Owing to changes in the PVT conditions in a hydrocarbon-filled structure, uplift and erosion increase the risk of leakage and expansion of the gas cap in a structure. Understanding of the timing of uplift and re-migration of hydrocarbons has been increasingly important in the exploration of the Barents Sea.

Palaeogeographic and tectono-stratigraphic considerations in the greater Barents Sea show that the distribution of reservoirs and hydrocarbon source rocks from the Late Palaeozoic to the Palaeogene can be related to three tectonic phases. Firstly, the Palaeozoic Caledonain Orogeny caused uplift to the west, followed by eastward sediment distribution across the shelf, towards carbonate platforms to the east. Secondly the Late Palaeozoic-Mesozoic Uralide Orogeny induced uplift to the east, causing widespread clastic deposition and reversal of the sediment distribution pattern. Thirdly, major Late Mesozoic-Cenozoic rifting and crustal breakup in the western Barents Sea led to the current basin configuration. Reservoir rocks comprise Late Palaeozoic carbonates and spiculites, Mesozoic terrestrial and marine sandstones and Palaeogene deep-water sandstones. Hydrocarbon source rocks range in age from Silurian to Early Cretaceous, and are grouped into three petroleum systems derived from Late Palaeozoic, Triassic and Late Jurassic source rocks. Multiple tectonic episodes caused formation of a variety of trap types, of which extensional fault blocks and gently folded domes have been the most prospective. Volumetric considerations of generated petroleum indicate that charging is not a limiting factor, except in the western margin.

The northern Barents Sea is divided into two principal prospective provinces: (1) the platform areas south and east of Svalbard contain possible hydrocarbon plays in Upper Palaeozoic clastics and carbonates, and in Mesozoic sandstones; (2) The Barents Sea margin, which includes the Yermak Plateau, with possible plays in late Mesozoic and Tertiary sandstones. The platform areas are underlain by a Palaeozoic rift system of highs and intervening basins, containing Devonian and Early Carboniferous rocks overlain by relatively flat-lying sequences of Late Palaeozoic and Mesozoic age. The Barents Sea margin is a complex basin province formed in response to phases of the Late Mesozoic and Cenozoic break-up of the Pangea supercontinent, and subsequent seafloor spreading west of Spitsbergen.The northern Barents Sea is as yet not open for commercial exploration, and no deep wells have been drilled in the offshore areas. It is one of the largest remaining frontier areas in western Europe and as such affords a wide range of exploration opportunities. However, the area is considered to be of high risk for petroleum exploration, with generally low statistical probabilities of discovery, largely because of the limited amount of data available to evaluate potential hydrocarbon plays, and in particular the presence, distribution, quality and maturity of source rocks. Hydrocarbon resource estimates are therefore characterized by large uncertainties.Potential reservoir rocks are identified, and seismic mapping has revealed many structural and stratigraphic leads on the Sentralbanken High, the Kong Karls Land Platform, the Gardarbanken High and in the Mesozoic and Tertiary sub-basins northwest of Bjørnøya. Future challenges will be focused on reducing uncertainties in mapping the distribution of source rocks of suitable quality. Limited basin modelling studies indicate that oil may have been generated and accumulated in many provinces, but better constrained models are required to evaluate Early Cretaceous thermal events and Late Cenozoic uplift processes that may have had negative effects on both oil generation and the retention of hydrocarbons in traps.

Kong Karls Land, easternmost in the Svalbard archipelago, displays a 300 m-thick Upper Triassic (Norian) to Lower Cretaceous (Aptian) succession. The islands are situated within a set of large-scale, NE-SW-trending folds. The sediments are poorly consolidated as a result of relatively shallow burial. Lower Cretaceous plateau lavas and sills cap the islands and have protected older strata from extensive Pliocene and Pleistocene erosion. Correlation between onland exposures and subsea seismic units shows that Kong Karls Land is a key reference area for the Late Triassic to Early Cretaceous development of the northern Barents Sea shelf, but also to the southwestern Barents Sea. The unique exposed succession can be correlated with nearby offshore data, enabling the recognition of key sequence stratigraphic surfaces which define major tectonic events. These enable subdivision of the succession into six tectonic megasequences (TMS 1 to TMS 6) of latest Permian to Early Cretaceous age. The TMS 1 is linked to denudation of the Uralian orogen and includes most of the northwestward prograding Triassic coastline in the northwestern Barents Sea and eastern part of Svalbard. The 200 m-thick estuarine to shoreface deposits of the Rhaetian to Pliensbachian TMS 2 in Kong Karls Land stands in contrast to the 5 to 20 m-thick condensed succession with numerous hiatuses in western Spitsbergen. This significant difference is suggested to be a response to an evolving foreland basin linked to the northern Barents Sea Basin and Novaya Zemlya Fold and Thrust Belt. The four youngest tectonic megasequences are represented by only thin remnants onshore and on the adjacent platform. Outcrop mapping and seismic profiles show high-amplitude weak folding in the Late Jurassic followed by Early Cretaceous reactivation, prior to deposition of the Helvetiafjellet Formation. The volcanism in Kong Karls Land is related to the High Arctic Large Igneous Province and opening of the Amerasian Basin, which resulted in uplift of the northern Barents Shelf and southwards tilting of the Svalbard Platform..

Paleogene formations on eastern Sørkapp Land contain common, reworked, Middle and Late Cretaceous terrestrial and marine microfloras. This observation questions the Late Cretaceous age reported for the Firkanten Formation in the Øyrlandet Graben on western Sørkapp Land, as the pollen and spores reported from this graben may not be in situ. The present palynostratigraphic data from the eastern Sørkapp Land suggest that the Firkanten and Basilika formations were deposited in a relatively short time-period during the Early to Mid Thanetian. The youngest Cretaceous deposits documented from the Carolinefjellet Formation in eastern Sørkapp Land are of Late Albian age.

The Upper Triassic, Jurassic and Lower Cretaceous succession on Kong Karls Land contains common to abundant, well preserved, marine and terrestrial palynomorphs. The palynological assemblages suggest a Norian age for the Flatsalen Formation, which comprises the oldest deposits exposed on the islands. The overlying Svenskøya Formation is dated as Norian/?Rhaetian to Early Toarcian. There are possible depositional breaks at the base of and within this formation. The overlying Kongsøya Formation is dated as Late Toarcian-Aalenian. There is no evidence of exposed Bajocian deposits on Kong Karls Land. The oldest, transgressive deposits of the Agardhfjellet Formation are dated as Bathonian, while the youngest part of this formation is of Kimmeridgian age. The oldest Cretaceous deposits exposed on Kong Karls Land are Valanginian-Hauterivian condensed carbonates assigned to the Tordenskjoldberget Member (Klippfisk Formation). Directly overlying the condensed unit are Upper Barremian, or possibly lowermost Aptian, marine shales of the Kolje Formation equivalent. The youngest rocks preserved on Kong Karls Land are fluvial deposits of the Hårfagrehaugen Member (Helvetiafjellet Formation) and the Kong Karls Land basaltic lava flows. The terrestrial palynomorphs found in the Håfagrehaugen Member support a latest Barremian to Aptian age for the Helvetiafjellet Formation, as suggested by the U-Pb geochronology.

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