The Barents Sea - Back in Business - A Tectonostratigraphic Approach to Petroleum Systems

Geir B. Larssen¹, Erik Henriksen⁴, Alf E. Ryseth¹, Turid Heide¹, Ketil Sollid¹, Kristin Rønning¹, Hans M. Bjørnseth¹, Tor K. Hals¹, Oddbjørn S. Kløvjan¹, Leif B. Henriksen¹, Ketil Kåsli¹, Antonina Stoupakova², and Tamara Kiryukhina^3
1Staoil Norway, Harstad, Norway.
²Staoil Moscow, Moscow, Russian Federation.
³Moscow State University, Moscow, Russian Federation.
⁴North Energy ASA, Alta, Norway.

The greater Barents Sea has just become “greater”. A median line apportioning the former “disputed area” (Figure 1) between Russia and Norway in the central Barents Sea was recently ratified by the Norwegian and Russian Authorities. This implies that the new area, “the Central Barents Sea” with a size of close to 173.000 km², will be opened for hydrocarbon exploration. Although little data, several big leads have been made public east of the former “median line” (original Norwegian claim area). These are partly stretching into the Norwegian sector. Additional exploration area with enhanced cooperation across borders, several new players and the newly Skrugard oil discovery, have increased drilling activity in the Norwegian sector. The Snøhvit gas field on stream and the giant Stockman gas field approaching a field development lead to a revitalisation of the greater Barents Sea.

Tectonically the Central Barents Sea is situated between sag basins in the east and a rift dominated terrain in the west. By merging geological data on both sides of the Russian-Norwegian borderline, a model for a working reservoir, hydrocarbon source rocks system and traps are indicated. Palaeogeographic and tectonostratigraphic considerations show that the distribution of reservoirs and hydrocarbon source rocks from the Late Palaeozoic to the Late Tertiary can be related to four main tectonic phases. Firstly, the Palaeozoic Caledonian orogeny causing uplift to the west followed by eastward sediment distribution across the shelf towards carbonates platforms to the east. Secondly, the Late Palaeozoic to Mesozoic Uralian orogeny produced uplift to the east, simultaneously with rifting in the west. This is causing widespread siliciclastic deposition and reversal of the sediment distribution pattern. Thirdly, major Late Mesozoic to Cenozoic rifting and crustal break-up in the western Barents Sea led to the current basin configuration. Finally, the Late Neogene uplift and net erosion with values varying from 0 m to more than 3000 m might have important consequences for the petroleum systems.

 

AAPG Search and Discovery Article #90130©2011 3P Arctic, The Polar Petroleum Potential Conference & Exhibition, Halifax, Nova Scotia, Canada, 30 August-2 September, 2011.

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