Numerical basin modelling of the Sleipner field, North Sea

Both one-dimensional (1-D) and two-dimensional (2-D) basin modelling has been carried out in the Sleipner area in the North Sea. Thermal refraction by salt and more minor convection by fluid transport combine to provide a temperature regime which is hotter at the Sleipner East field relative to the Sleipner West field by approximately 5°C at the same sub-surface depth. These results are obtained only with 2-D modelling, and show that such simulations are necessary to explain the spatial variations of temperature distribution at the least. Modelling of hydrocarbon generation in the Sleipner kitchen shows that the source rocks are presently in a late gas generation state, and that a gas-condensate is to be expected in fields draining this kitchen. Such hydrocarbon phases are encountered in the Sleipner field, confirming that the model can simulate satisfactorily hydrocarbon generation in the Sleipner area.