A Technical Approach to 3D Modelling of the Subsurface Geology in the South-Eastern Harz Foreland

The digitization of geological data is becoming increasingly important in the assessment of the subsurface geology, and 3D visualization offers new possibilities. To extend the visualization of the subsurface geology of the State of Saxony-Anhalt, a 3D structural model of Permian to Quaternary stratigraphy of the South-Eastern Harz Foreland has been created. The model is based on pre-existing data consisting of maps from large-scale subsurface exploration, seismic profiles, and c. 5,660 stratigraphic profiles from the extensive borehole database from over 100 years of drilling exploration. Data preparation consisted of extracting borehole data, digitizing and vectorizing maps and seismic profiles, and subsequent processing with ArcGIS. Modelling of the surface mesh of stratigraphic boundaries and faults was performed using SKUA-GOCAD 22 in the 'Structure and Stratigraphy' workflow. In this iterative process, inconsistencies in the topology and geometry of the mesh have to be resolved manually in several steps in order to create a consistent model. Challenges arise from low data density in some areas and conflicting information in data from different sources. The resulting model shows the arrangement and relationship of stratigraphic units and major faults of the area in a refined level of detail. Within the requirements of publication and provision of state geological data by the Geological Survey of Saxony-Anhalt (LAGB), the model was prepared to be published via the GST (Geosciences in Space and Time) framework at the LAGB.