Attributed 3D volumetric models are important tools for planning resource exploration, subsurface storage of natural gases and waste and for risk management. Of particular interest are subsurface temperatures and lithological attributes, which reveal important evidence on geothermal potential, characteristics of deep aquifers and reservoir rocks and support project planning.
A harmonized 3D structural model of the entire North German Basin was prepared in the scope of the project "Potentials of the underground storage and economic area in the North German Basin" (TUNB). The current second project phase is focused on parameterizing this model with various petrophysical and geological parameters. Here, we present our approaches and results for modeling subsurface temperatures, lithologies and clay contents in the area of Northern Saxony-Anhalt.
Temperature gradients from borehole logs were applied to model formations and adjusted to the thicknesses of the highly thermally conductive Zechstein formation for calculating subsurface temperatures. Lithological information were derived from a comprehensive lithologic-paleogeographic map series. Shale fractions were qualitatively estimated from petrographic descriptions and quantitatively confirmed using gamma ray logs. Subsequently, a fault seal analysis was performed based on clay contents and the lithofacies model. The results demonstrate the numerous possibilities for large-scale parametrization with discrete and continuous parameters and form the basis for comprehensive information systems and databases for further project planning and prospection efforts.