detect-µ

To a large part, the seismicity of Switzerland is characterized by swarm-like earthquake sequences of natural, and to a minor extent of man-made origin. Many of these sequences have been studied using relative location techniques, which often allowed to constrain the active fault plane of the larger events in a sequence and shed light on the tectonic processes that drive the seismicity. Yet, in the majority of cases the number of located earthquakes was too small to infer the details of the space-time evolution of the sequences, and their statistical parameters (e.g. magnitude-frequency distribution, Omori parameters). Therefore, it has been largely impossible to resolve clear patterns in the seismicity of individual earthquake sequences that are needed to improve our understanding of the mechanisms behind, and the differences between natural and induced earthquake sequences.

In this project we aim to significantly improve the completeness of detected and located earthquakes in the Swiss catalog. We plan to develop techniques that take advantage of the waveform similarity in natural and induced earthquake sequences to detect seismic events several orders of magnitude below the detection threshold of classical signal energy based detectors. Waveform similarity will than further be exploited to derive accurate and consistent magnitudes and locations for even the smallest events of the sequences.

Building on the data from this analysis we plan to study the processes and physics behind natural and induced microseismicity, e.g.:

• understanding why natural earthquakes occur in swarm-like sequences
• identifying triggering mechanisms of natural and induced earthquake sequences
• understanding the differences and similarities of natural and induced earthquake sequences
• detect and study repeated earthquakes