POTENTIAL CO2 STORAGE SITES IN THE GERMAN NORTH SEA? A RESERVOIR-MODELLING AND PARAMETRIZATION STUDY

Carbon dioxide removal and storage is required for limiting global warming to the 2 °C goal of the Paris Agreement. One method is the storage of CO₂ in deeply buried geological formations.

As part of the GEOSTOR project, we created static 3D models for two potential storage sites in the Middle Buntsandstein within the German North Sea Exclusive Economic Zone.

One 3D geological model (~1300 km²) located on the "West Schleswig Block" is based on 2D seismic data from various surveys and geophysical logs from four exploration wells. It encompasses a salt controlled anticline with 40-50 m thick Lower Volpriehausen Sandstones forming the primary reservoir target. The top seal consists of Upper Buntsandstein and unconformable Lower Cretaceous mudstones.

The other 3D geological model (~560 km²) is located within the “Entenschnabel” area and, in contrast, is based on several high-resolution 3D seismic data and geophysical logs from four exploration wells. The reservoir, which also consists of up to 65 m thick Lower Volpriehausen Sandstones, is located within the Mads Graben with erosional discordances at the top. The upper seal consists of Upper Jurassic clays and partly unconformable Lower Cretaceous mudstones.

For both models we conducted petrophysical analyses of all considered well data and calculated reservoir properties to determine the static reservoir capacity for these storage sites.

Finally, we parametrized both models in order to provide two complete reservoir models that are capable of further dynamic capacity simulations, geo-risk and infrastructural analyses aiming at an entire feasibility study within the project framework.