Source-rock maturation characteristics of symmetric and asymmetric grabens inferred from integrated analogue and numerical modeling: The southern Viking Graben (North Sea)

We present the results of an integrated analogue and numerical modeling study with a focus on structural, stratigraphic and thermal differences between symmetric and asymmetric grabens. These models enable fault interpretation and subsidence analyses in studies of active rifting and graben migration. We imported the surface topography and crustal thinning factors from the analogue models into tectono-stratigraphic forward models which allowed an assessment of the relative importance of sediment stacking in the generation of symmetric and asymmetric grabens. Effects on source-rock maturation zones were calculated through 1D-thermal modeling for different graben types. Combined analogue-numerical modeling appears to be a useful method to simulate natural examples, as shown in this study of the southern Viking Graben in the northern North Sea. This area was formed by Early Permian-Late Jurassic extension, with rifting most intense during the Late Jurassic. The thermal structure of the model, constrained by lithospheric and sedimentary parameters for this region, compares well with actual source-rock maturation data on the southern Viking Graben.