Le attività del gruppo operativo SISMIKO in occasione del terremoto di Ischia MW 3.9 (MD 4.0) del 21 Agosto 2017

Abstract

After the MD 4.0 (Mw 3.9) earthquake of August 21 2017 which occurred on the Ischia island, the SISMIKO group [Moretti et al., 2016a; 2016b], which is the coordinating group of the emergency seismic networks of INGV, was activated and four seismic mobile stations were installed in the district of Casamicciola and Lacco Ameno integrated with the permanent network on the island. At the beginning, for the first three months, all the mobile stations, coded as T13 network, acquired locally and were equipped with short period sensors and one accelerometer. Starting from October 2017, the seismic signals for three of the four stations, in separate times from October 2017 to May 2018, were transmitted in real time to the INGV monitoring acquisition room for surveillance purposes. Nowadays, the mobile seismic network on the island is composed by six stations: three of them are telemetered while the others recorded signals on local disks. The seismic stations were equipped with short period sensors LE3Dlite 1Hz, LE3D 5s and FBA-­EST Kinemetrics accelerometers. Although starting from September 2017, the seismicity of Ischia island was characterized by few low magnitude earthquakes, the installation of mobile stations T13 improved the performance of the seismic network either for the localization analysis or for the detection of very low magnitude earthquakes.