Deep geothermal energy in Germany has the potential to play an important role in order to achieve the climate protection goals - especially in the field of heat transition. For this reason, all possible risks concerning deep drilling, exploration and production have to be further reduced. In this regard, the geomechanical integrity of the subsurface is of crucial importance as it significantly influences reservoir quality, wellbore stability and occurrence of induced seismicity. Apart from geomechanical rock parameters, the geomechanical integrity of the subsurface is mostly controlled by the difference between the minimum principal stress magnitude and the pore pressure, also known as effective stress.
The project is intended to help reduce both, risks and production costs of deep geothermal projects in Germany. Therefore, a comprehensive database on pore pressure and thus effective stresses is supposed to be presented within the World Stress Map project for the first time. Pore pressure data and minimum effective stresses are of utmost importance for well design in deep drilling, especially when optimal mud weight, casing landing depth and wellbore integrity need to be defined. In a next step this database is supposed to be used for developing the new well management toolkit EFFECT. This toolkit should enable to automatically predict minimum effective stresses and wellbore integrity using data on wellbore location and well design only. The toolkit will therefore be validated through an industry partner regarding its suitability and sensitivity with respect to real data. Besides, its manageability will be optimized as well. The availability of a database which covers both, pore pressures and effective stresses as well as the provision of a toolkit which allows for standardized high-quality parameter prediction would not only be unique in the world. It would thereby also provide socio-economic and safety-relevant benefits to the deep geothermal industry in Germany.
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