PETROLEUM SYSTEMS MODELLING OF THE MUENSTERLAND BASIN AND RUHR BASIN WITH SPECIAL EMPHASIS ON UNCONVENTIONAL GAS RESOURCES

The Muensterland Basin is characterized by an Upper Cretaceous basin fill which is separated by an unconformity from Upper Carboniferous sedimentary rocks, which were deposited in the Variscan foreland basin and contain the most important anthracite and hard coal reserves in Germany. The depth of the top Carboniferous ranges from about 1.5 km close to the city of Muenster in the north to 0 km at the southern rim, where Carboniferous rocks crop out at the surface.

This study deals with the geological evolution of the Muensterland Basin/Ruhr Basin with special emphasis on the Palaeozoic petroleum systems including its unconventional gas resources. Various data bases were used to construct a 3D model (PetroMod^® suite software) for this region, reaching from the Lower Saxony Basin in the north to the Rhenish Massif in the south and from westernmost Germany to the Egge Fault south of the city of Minden. The model represents an area of 110 km (length) by 152 km (width) with a horizontal resolution of 500*500 m (220*304 cells). It covers the whole Muensterland Basin and comprises important tectonic elements including the Variscan front with important faults in the Carboniferous as well as the Osning Fault in the Northwest.

A few studies on basin modeling were performed in the past, but focused on the southern margin of the basin and no 3D petroleum systems model has been published so far. It is known from these studies that maximum burial and hence thermal maturation occured at the end of Carboniferous times.

Physical parameters, such as porosity and permeability, which characterize the individual lithologies present in the basin, have been assigned to the strata in the model. Also, chemical properties of varying source rocks have been summarized for this model. Paleozoic rocks contain numerous unconventional gas resources. These include coalbed methane (CBM) within the coal-bearing Pennsylvanian sequence, organic-rich shales in the Mississippian (Lower Carboniferous) and possibly also in the Pennsylvanian and Pre-Carboniferous.

The goal of this study is to focus on the geodynamic evolution of the Muensterland region and use these results to calculate maturity levels, temperatures and other related parameters in a fully integrated numerical petroleum systems model.