Search for Alternative Plays on Barents Shelf

Randi Carlsen, Elisabet Malmquist, Geir Mork, David Worsley

Exploration in the Norwegian sector of the Barents Shelf has covered only a small part of this almost 500,000-km² province. Main targets have been Jurassic reservoirs and sources in most wells drilled to date. New block allocations are now moving exploration activities eastward and northward into provinces with untested potential. Successful operations in these areas demand regional depositional models for pre-Jurassic sequences not previously regarded as primary exploration targets. These models are built upon syntheses of shelf-derived data with information from Svalbard, the Sverdrup basin, and Timan Pechora. Important tectonic constraints are provided by the area's special position at the northwest corner of the European plate, affected by the interplay of ovements connected to the evolution of both western and northern plate margins.

Large shelf areas are underlain by mid-Carboniferous to mid-Permian carbonate sequences. Important factors in petroleum source and reservoir identification here are platform and basinal configurations as affected by large-scale tectonic movements along western shelf margins.

Late Permian to mid-Triassic regional subsidence produced clastic play types, with a source potential which reflects progressive onlap of structural highs and the infilling of preexisting basinal relief. A short-lived Late Triassic switch in depositional styles suggests large-scale uplift along northeastern shelf margins. This produced major southwest-directed deltaic progradation over the entire area, with high depositional rates. Reservoir potential of this sequence may be inhibited by the textural immaturity of sandstones deposited in the deltaic complex.

AAPG Search and Discovery Article #91038©1987 AAPG Annual Convention, Los Angeles, California, June 7-10, 1987.