Induced seismicity in Germany during the last decade – an overview and update

The Federal Seismic Survey at BGR evaluates seismic events in Germany and neighbouring countries on a daily basis. The results are supplemented by the outcomes of the seismological agencies of the federal states of Germany and German universities and stored in an event database and in the German earthquake catalogue.

The events are classified as natural earthquakes, induced earthquakes or explosions (mostly quarry blasts). A considerable number of the events are induced earthquakes. They originate from stress changes due to human activities in the subsurface. The main causes of the induced events are coal mining, potash salt mining, natural gas extraction and geothermal energy production.

We describe the characteristics of the associated seismicity for the different mining regions in Germany. In contrast to natural seismicity which originates in long-term processes, the number and strength of induced seismicity is strongly dependent on rather short-term temporal and spatial changes.

The seismicity in coal mining regions, e.g., decreased coinciding with the shutdown of coal mining, whereas seismic activity in geothermal or natural gas fields show different behavior, increasing or decreasing depending on the location. Additionally, the latter both types of induced seismicity show remarkable peculiarities in their temporal behavior.

We show the temporal course of induced seismicity over the last 10 years in dependence on the distinct extraction types and compare it with the previous decades. In addition, we also investigate the magnitude-frequency relationship and the energy release of the induced earthquakes and compare the parameters with those of the natural seismicicity.