The scientific focus of the Section is on the integrated, deterministic and quantitative investigation of coupled processes in shallow to deep groundwater. The understanding of these processes should be further developed so that all spatial and temporal time frames can be covered and simulated.
Both the water provision framework plan and the utilization of groundwater systems (georesources) generally provide for a time frame of about 30 years for planning and authorization processes (water management time periods), while the understanding of processes involved in the interactions between deep and shallow groundwater systems requires long-term time frames of at least 1,000 years.
Today, detailed investigations of the various time scales in spatial terms can be performed using numerical simulations on high-performance computing systems. These will be important instruments in the future for predictions and hazard assessments relating to groundwater problems. The system analysis of groundwater zones is performed with numerical simulation programs, some of which are commercially available, and others being further or newly developed by the Fluid Systems Modelling Section.
The focal point in this area is the simulation of thermal, hydraulic, mechanical and chemical coupled processes. Existing and still to be recorded field data on groundwater hydraulics, hydrochemistry and geomechanics represent an important basis for the numerical simulation. In the area of computer-assisted simulations, the optimization of the programs and the use of high-performance computers will play an important role.
Moreover, upscaling and stochastic simulation methods used for describing the geometry and spatial distribution of the parameters that are relevant for simulations are being applied and further developed. Within the scope of process simulation, coupled processes are numerically investigated in terms of the interactions between deep and shallow aquifers. The goals here are, among other things, the assessment of the influence of the utilization of the geological subsurface, and the prediction of the long-term behaviour of the coupled groundwater systems.
Research performed by this section includes the following topics:
• Development of statistical geological models in consideration of the structural geological boundary conditions (Figure 2).
• Integration of observation data from current projects on subsurface utilization (e.g. data from borehole measurements and geophysics at the pilot site Ketzin - Centre for CO2 Storage) into the dynamic simulation models.
• Validation of model implementation and simulation results using available data sets from real sites (Figure 2).
• Integration of geochemical and geomechanical processes into numerical simulators (process coupling in models).
• Provision of long-term predictions and integrated risk analyses for utilization concepts of the geological subsurface (e.g. in terms of the assessment of saltwater migration and coupled geoprocesses).
• Investigation of thermal-hydraulic coupled processes at various spatial and temporal scales.
• Integration of numerical models to optimize geophysical monitoring methods.
• Effects of heterogeneous permeability fields on the dynamics of saltwater migration.
• Preparation of economic analyses and modelling of interactions with the utilization of the geological subsurface.