A new Multidisciplinary Marine Monitoring system for the surveillance of Volcanic and seismic areas

Abstract

A seafloor multisensor module with real-time data transmission, known as CUMAS, has been successfully deployed in the Gulf of Pozzuoli, in the Campi Flegrei caldera, which is one of the most hazardous volcanic areas in the World. CUMAS records seismological signals and provides measurements related to the water-current system. A test for the detection of sea level changes, potentially related to the seafloor uplift or subsidence, is ongoing with the use of the pressure gauge data. A surface buoy is equipped with additional sensors for meteorological measurements and receives the continuous scientific and status data streams from the CUMAS station via cable. These data are then transmitted by a wireless system to the INGV monitoring center in Naples. CUMAS is fully integrated into the geophysical land-based monitoring system that is managed by INGV, and it is the first off-shore station of the local network. An Earthworm-based system provides userfriendly data visualization and retrieval, which was adopted to straightforwardly integrate all of the data acquired by CUMAS with the land data, which is managed by a similar system. Following the results of a previous investigation performed using two ocean-bottom seismometers that were deployed in Pozzuoli Bay (Vassallo et al. 2008), CUMAS was deployed in a site that was selected to improve the performance of the present seismic network in terms of the detection threshold of the local seismicity and of hypocenter errors. CUMAS will provide long time-series data that will allow, for the first time, the study of the evolution of the volcanic activity and related phenomena in the marine sector of the Campi Flegrei caldera, which to date has only been investigated on the basis of land data. CUMAS is the first node of a marine network that is at present the subject of a feasibility study that will cover most of the submerged Campi Flegrei volcanic area and will be integrated into the local monitoring systems.