Geological Modeling 4.0

Abstract

Knowledge about the geological subsurface is important for a variety of industrial and technical applications: as a resource of mineral and non-mineral raw materials, as a reservoir, and as a planning ground for underground infrastructure—and in this context also increasingly in the context of urban planning and “Building Information Management” (BIM) extended into the subsurface, often also referred to as GeoBIM (Svensson 2015). The central problem of characterizing significant rock and fluid properties in the subsurface is that, to date, there is no inexpensive and comprehensive way to directly measure these properties. Although (expensive) boreholes provide very precise information at specific points, extrapolation into space is only possible indirectly with the aid of geophysical measurements. In particular, seismic, gravimetric, and electromagnetic measurements are often used for this purpose (e.g., Telford et al. 1990). From all this information, a geometric structural model is typically created, in which rocks are grouped into formations that show similar properties in the context of the investigation. This view is conceptually illustrated in Fig. 1 for a typical rock sequence, here as an example with a photograph from an outcrop (Fig. 1a). If we now imagine that this rock sequence is not at the surface but in the subsurface, then we often have only very isolated direct observations in the direct vicinity of these boreholes (Fig. 1b). The crucial question then is how these observations can be interpolated in space, between the known points and extrapolated beyond them. Combining geological and geophysical aspects, an attempt is typically made to determine interfaces between units with similar properties (Fig. 1c).