Can Uplift Of Structural Highs Explain Distribution Of Inversion And Compression in The Southwestern Barents Sea?

Ivar Grunnaleite¹ and Ziping Huang^2
1IRIS (Int. Research Inst. of Stavanger), N5008 Bergen, Norway
²Norconsult AS, N1338 Sandvika, Norway

Compressive structures and signs of structural inversion are widespread in the southwestern Barents Sea. Many processes are suggested as cause for the compression, but not all observations can easily be explained by simple horizontal compressive mechanisms. For instance reverse faults with up to NW-directed compressive motion are described from seismic data and are difficult to explain by the commonly suggested mechanisms, generally creating SE-directed compression. Numerical modelling of the uplift and bending stress effect proved that compressive stress directed against the expected SE directed compression can occur in the eastern flanks of the uplifted highs of the SW Barents Sea. We suggest that the effects of Cretaceous and Cenozoic uplift and associated bending of the structural highs and their border faults directly affect deformation in the adjacent basins and in the uplifted highs themselves. This article does not favour one particular cause for the inversion. Instead it is focused on local variations and local effects of different mechanisms. The main conclusion is that the mechanical effect locally of vertical forces applied by flank uplift and sediment loading must be taken into consideration and may explain the observed distribution of compressional structures no matter what mechanism that initially caused the observed uplift or contemporaneous compression.

AAPG Search and Discovery Article #90072 © 2007 AAPG and AAPG European Region Conference, Athens, Greece