Use of underground geosystems
Approximately 24 billion cubic meters of natural gas will be stored underground in Germany. These subterranean reserves could provide gas throughout Germany for a quarter of a year. In addition to underground storage, the uses of subsurface geostructures include the production of energy and raw materials as well as the storage of hazardous substances such as radioactive waste. The use of the subsurface poses major technical challenges for both society and industry. Geological research plays a significant role in the search for potential solutions to these challenges.
The exploitation of resources from subsurface geosystems has increased significantly in recent years and has sparked debates regarding its possible impacts on those components of nature which are fundamental to life, e.g. groundwater contamination, soil contamination, air pollution and induced seismic events. Accordingly, we can expect the future exploitation of the natural subsurface to be increasingly riddled with usage conflicts. In addition to conventional types of exploitation such as mining and tunnel construction, there has been an increasing administrative and economic focus on the use of new technologies for the production of energy and sources of energy as well as the long and short-term geological storage of materials (e.g. natural gas, hydrogen, and compressed air), thermal energy, and the safe storage of waste. The responsible and sustainable utilization of our underground georesources requires targeted scientific studies aimed at achieving a quantitative understanding of the complex relationships in an anthropogenically-influenced environment which will, in turn, enable us to make predictions which can be validated.
As of July 2017, the Federal Ministry of Education and Research (BMBF) has been funding a total of eleven cooperative projects dealing with the topic of the "Exploitation of Underground Geosystems." This funding supports research and development (R&D) which enhances our understanding of the processes and systems occurring in subsurface geology, as this is an important prerequisite for the sustainable geotechnological exploitation of both shallow and deep geosystems.
The scientific studies in this area will focus on the key topics of reactive multiphase transport processes and the geomechanical integrity of reservoir rocks and barrier rocks. Research objectives of particular importance are the detection, description and simulation of temporal and spatial changes in the permeability of the rock layers due to the geochemical interactions between the transported fluid phases and the solid phase under varying temperature and pressure conditions. To this end, natural disturbance zones and anthropogenic damage to caprocks will be studied as possible pathways for the migration of fluids and gases from deep geological reservoirs in order to evaluate the effects on the near-surface groundwater systems.
These studies of basic process must be considered squarely in the scientific context of technologies such as deep and near-surface geothermal energy, heat storage in deep and near-surface geosystems, the development of conventional and unconventional hydrocarbon storage facilities and the deep underground retention or storage of gases or fluids.