Towards a Real-Time Forecast of Induced Seismicity for Enhanced Geothermal Systems

The development of novel technologies such as Enhanced Geothermal Systems (EGS) has been decelerated due to induced seismicity. Sophisticated traffic light systems, which assess the seismic hazard in time for taking precautionary measures, can assist in the successful development of EGS sites close to urban areas. We present here the modeling approach for a hybrid model that can be used in such a traffic light system. This hybrid model combines the HFR-Sim software with stochastic models that have been used for forecasting induced seismicity. HFR-Sim is an EGS simulator, which can model flow inside dynamically changing fracture networks. It offers discrete representation of fractures, and can be used for simulating a wide range of three dimensional problems, which are related to the design, creation and operation of an EGS reservoir. Here, the coupling of HFR-Sim with a stochastic seed model is explained. Exemplary simulations are performed with the resulting software and the results obtained by those simulations are discussed.

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