Conceptual 3D geological model for the Střešovice railway tunnel
The conceptual geological 3D model of the area of interest was created in the modeling software MOVE 2019.1 developed by Petroleum Experts ltd. The aim of the model is a unified visualization of geology and faults below the surface in relation to the planned variants of the railway tunnel. The model includes Quarternary cover, platform Cretaceous sediments and Ordovician sediments of the Prague Basin that underwent Variscan deformation.
During the whole modeling process, a general geological rule was applied when creating lithological boundaries: younger lithostratigraphic units intersect older units. The fault network was modeled by a qualified extrapolation and subsequent extrusion of the surface course of the faults according to the dip estimated for each fault separately. The modeled fault network was then used as one of the limitations in modeling adjacent rock bodies. Modeling of geological bodies was performed by two fundamentally different approaches: Quaternary and Cretaceous sediments were modeled as subhorizontal to slightly inclined surfaces in MOVE and also in ArcMap GIS using depth data from reinterpreted boreholes and from the surface boundary of the occurrence of the corresponding units, using interpolation algorithms. Paleozoic formations represent a lithologically variable environment deformed in ductile mode during Variscan orogeny. Their boundaries were modeled manually and individually, based on an expert assessment of the geological position and structural data from the vicinity of each body and on the basis of consultations with a geologist specializing in the Paleozoic of the Prague Basin.