Reservoir Modelling and Production Experience of a Heterogeneous Rotliegend Reservoir; K18-Golf Gas Field Netherlands

The K18-Golf gas field was discovered in 2005. The reservoir consists of a 270 m thick Rotliegend (Permian) sandstone reservoir with average porosities of less than 10%. The reservoir quality is very heterogeneous and of a tight nature with average permeabilities of 0.6 mD. The development started in 2011 with one horizontal and one vertical well, which both were hydraulically fracced. The horizontal well was producing above expectation and the vertical well produced lower than expected, due to poor connectivity. An additional horizontal well drilled in 2015 showed preferential depletion of layers and blocks. Since the last static model, created in 2013, the results of the well drilled in 2015 became available and a new 3D seismic survey was acquired. A new reservoir model has been built in an integrated team environment to explain reservoir behavior and plan potential infill opportunities. The seismic and static model had to be revisited several times to explain and match the dynamic behavior.