TY  - JOUR
A1  - Beyreuther, Moritz
A1  - Hammer, Conny
A1  - Wassermann, Joachim
A1  - Ohrnberger, Matthias
A1  - Megies, Tobias
T1  - Constructing a hidden Markov Model based earthquake detector: application to induced seismicity
JF  - Geophysical journal international
N2  - The triggering or detection of seismic events out of a continuous seismic data stream is one of the key issues of an automatic or semi-automatic seismic monitoring system. In the case of dense networks, either local or global, most of the implemented trigger algorithms are based on a large number of active stations. However, in the case of only few available stations or small events, for example, like in monitoring volcanoes or hydrothermal power plants, common triggers often show high false alarms. In such cases detection algorithms are of interest, which show reasonable performance when operating even on a single station. In this context, we apply Hidden Markov Models (HMM) which are algorithms borrowed from speech recognition. However, many pitfalls need to be avoided to apply speech recognition technology directly to earthquake detection. We show the fit of the model parameters in an innovative way. State clustering is introduced to refine the intrinsically assumed time dependency of the HMMs and we explain the effect coda has on the recognition results. The methodology is then used for the detection of anthropogenicly induced earthquakes for which we demonstrate for a period of 3.9 months of continuous data that the single station HMM earthquake detector can achieve similar detection rates as a common trigger in combination with coincidence sums over two stations. To show the general applicability of state clustering we apply the proposed method also to earthquake classification at Mt. Merapi volcano, Indonesia.
KW  - Time-series analysis
KW  - Neural networks
KW  - fuzzy logic
KW  - Seismic monitoring and test-ban treaty verification
KW  - Volcano seismology
Y1  - 2012
U6  - https://doi.org/10.1111/j.1365-246X.2012.05361.x
SN  - 0956-540X
VL  - 189
IS  - 1
SP  - 602
EP  - 610
PB  - Wiley-Blackwell
CY  - Malden
ER  -