A test is being realised by means of a network of wide band electromagnetic detectors that continuously records the electric components of the electromagnetic field, ranging from a few of Hz to tens of kHz. The networ...A test is being realised by means of a network of wide band electromagnetic detectors that continuously records the electric components of the electromagnetic field, ranging from a few of Hz to tens of kHz. The network has been operating in central Italy for more than ten years. The recorded signals from this network have been analysed in real time as well as their power spectrum contents. Time/frequency data have been saved for further analysis. The spectral contents have evidenced very distinct power spectrum signatures in ELF band that increase in intensity when strong seismic activity occurs near the stations, for example, at the time of Amatrice (M = 6) and Norcia (M = 6.5) earthquakes in 2016 when ten stations were operative, at the time of the Emilia (M = 6) earthquakes in 2012 when nine stations were operative, and at the time of the L’Aquila (M = 6.3) earthquakes in 2009 when only two stations were operative. Strong signals were also detected during the moderate Ancona (M = 5) earthquake in 2013 and by the recently installed Avigliano Umbro, Città di Castello and Gubbio stations in the Umbria region, during small seismic swarms (2 < M < 4) between 2013 and 2014. CIEN is presently composed of 16 stations and collect data from a multidisciplinary instrumentation.展开更多
文摘A test is being realised by means of a network of wide band electromagnetic detectors that continuously records the electric components of the electromagnetic field, ranging from a few of Hz to tens of kHz. The network has been operating in central Italy for more than ten years. The recorded signals from this network have been analysed in real time as well as their power spectrum contents. Time/frequency data have been saved for further analysis. The spectral contents have evidenced very distinct power spectrum signatures in ELF band that increase in intensity when strong seismic activity occurs near the stations, for example, at the time of Amatrice (M = 6) and Norcia (M = 6.5) earthquakes in 2016 when ten stations were operative, at the time of the Emilia (M = 6) earthquakes in 2012 when nine stations were operative, and at the time of the L’Aquila (M = 6.3) earthquakes in 2009 when only two stations were operative. Strong signals were also detected during the moderate Ancona (M = 5) earthquake in 2013 and by the recently installed Avigliano Umbro, Città di Castello and Gubbio stations in the Umbria region, during small seismic swarms (2 < M < 4) between 2013 and 2014. CIEN is presently composed of 16 stations and collect data from a multidisciplinary instrumentation.