SN-1: the first node of the Italian seafloor observatory network background and perspective

On the 9th of October 2002, the seafloor observatory SN-1 (Submarine Network-1) was successfully deployed in 2015 m w.d. offshore Catania (southern Italy) and was successfully recovered on May 12, 2003. The observatory worked properly for 130 days (depending on the power of the lithium battery), acquiring high quality seismic, gravimetric and environmental signals. SN-1 has been developed within a project funded by the Italian National Group for the Protection against Earthquake (GNDT) and co-ordinated by the Istitituto Nazionale di Geofisica e Vukcanologia (INGV) and takes advantage of a partnership including Universities, Research Institutes, and the industrial company Tecnomare (ENI Group). SN-1 was straightforward derived from the previous GEOSTAR observatory, funded by the European Commission in the period 1995-2001, which performed a deep-sea mission of 7 months in 2000-2001 at about 2000 m w.wd. in the southern Tyrrhenian Sea. In the next future SN-1 observatory will be connected to a submarine cable owned and deployed by the Italian National Institute for Nuclear Physics (INFN), having the main purpose to support a scientific pilot experiment of natural neutrino detection in deep sea (Neutrino Mediterranean Observatory, NEMO Project). This will make possible the real-time data transmission and communication, and therefore the complete integration of SN-1 to the existing land-based network, and significantly contribute to the knowledge of a key sector of the Central Mediterranean Geodynamics. Presently SN-1 is the longest worldwide seismological experiment (130 days) on the deep seafloor.