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.

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During specific intervals within Mesozoic and Cenozoic times, several areas of the southwestern Barents Sea were subjected to uplift and erosion. Areas with missing shallow stratigraphic interval sections and major erosion can be seen at several places along interpreted regional profiles in the southwestern Barents Sea. A new Normal Compaction Trend (NCT) for two selected shale-and sandstone-dominated lithologies has been constructed based on sonic logs in the southwestern Barents Sea. The shale-dominated NCT is calibrated to the Cretaceous shales in the Northern North Sea and Norwegian Sea and applied to the Cretaceous

All of the Arctic Eurasian Basins -the Barents and Kara Seas and the adjacent parts of the Pechora and West Siberian basins -have intracratonic settings and were affected by phases of intracratonic rifting during Riphean, Early Palaeozoic, Devonian-Early Carboniferous, Early Triassic, Jurassic and Cenozoic times. Often these stages were simultaneous at remote areas. The rifting led to the development of extensional sag basins giving thick sedimentary complexes associated with linear rifts and creating trends favourable for hydrocarbon generation. These trends are defined by the major fault complexes bordering them and include linear positive inverted structures and thick sedimentary complexes. The tectonic processes within these trends influenced the later structuring of the whole basin and the distribution of hydrocarbons. Hydrocarbon generation started long before the present basins' structural configuration formed, and oil and gas kitchens were associated mainly with extensional parts of the basins. Later phases of rifting and extension affected both the ancient oil and gas kitchens and the younger ones. Inversion caused trapping and affected fluid migration, mixing the petroleum systems. Inverted structures in the old rifts have the highest potential for large hydrocarbons accumulations but, in highly uplifted areas affected by faulting and erosion, exploration risk is high.