Chapter 10 Tectonostratigraphy of the greater Barents Sea: implications for petroleum systems

Abstract

Abstract 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.