Publication Date:
2017-04-04
Description:
Timely identification of changes in the state of volcanoes and onset of potentially dangerous eruptive
phenomena requires efficacious surveillance methods. In the case of an active volcano like Mt Etna, the
continuous background seismic signal called volcanic tremor is of paramount importance. The huge amount
of continuously acquired digital data entails the necessity of data reduction and parameter extraction. For this
purpose, techniques of automatic analysis of volcanic tremor were applied by INGV for the real time
monitoring of this signal. We checked the possibility to identify regimes of volcanic activity based on pattern
classification of volcanic tremor. A specific software named “KKAnalysis” was developed. It combines
various unsupervised classification methods (Kohonen Maps and fuzzy cluster analysis) and forms the
backbone of an automatic alert system at INGV-OE. Besides its near real time application, it can be operated
off-line, allowing an efficient a-posteriori processing of data and tuning of the alarm criteria to match
specific needs of sensitivity and robustness. An ongoing development of this tool will allow us to include a
large number of seismic stations in a multistation-alarm system. The new system will be more robust in case
of failure of single sensors, and will achieve a better coverage of the various eruptive craters. In an off-line
test, we exploited a dataset covering eight years of seismic records, and analysed the performance of the new
system in terms of “trigger timing” and spatial distribution of the stations. Intriguing results were obtained
throughout periods of renewal of volcanic activity at Bocca Nuova-Voragine and North East Crater, and in
the absence of paroxysmal phenomena at South East Crater and New South East Crater.
Description:
Published
Description:
Nicolosi (Catania, Italy)
Description:
2V. Dinamiche di unrest e scenari pre-eruttivi
Description:
open
Keywords:
Etna, Volcanic tremor
;
Self Organizing Map, Fuzzy clustering
;
Volcano monitoring, Pattern recognition
;
04. Solid Earth::04.06. Seismology::04.06.06. Surveys, measurements, and monitoring
;
04. Solid Earth::04.06. Seismology::04.06.08. Volcano seismology
;
05. General::05.01. Computational geophysics::05.01.01. Data processing
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
Poster session
