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The SEISMOFAULTS project (www.seismofaults.it) was set up in 2016 with the general plan of exploring the seismicity of marine areas using deep seafloor observatories. The activity of the first two years (Seismofaults 2017 and 2018) consisted of the installation of a geophysical-geochemical temporary monitoring network over the Ionian Sea floor. Eleven ocean-bottom seismometers with hydrophones (OBS/H) and two seafloor geochemical-geophysical multiparametric observatories were deployed to: (1) identify seismically active faults; (2) identify potential geochemical precursors of earthquakes; and (3) understand possible cause–effect relationships between earthquakes and submarine slides. Furthermore, five gravity cores were collected from the Ionian Sea bottom and ~4082 km of geophysical acquisition, including multibeam and single channel seismic reflection data, were acquired for a total of 4970 km 2 high-resolution multibeam bathymetry. Using Niskin bottles, four water column samples were collected: two corresponding at the location of the two multiparametric observatories (i.e., along presumably-active fault zones), one corresponding at a recently discovered mud volcano, and one located above a presumably-active fault zone away from the other three sites. Preliminary results show: (1) a significant improvement in the quality and quantity of seismological records; (2) endogenous venting from presumably active faults; (3) active geofluid venting from a recently-discovered mud volcano; and (4) the correct use of most submarine devices. Preliminary results from the SEISMOFAULTS project show and confirm the potential of multidisciplinary marine studies, particularly in geologically active areas like southern Italy and the Mediterranean Sea.

A real-time urban seismic network for seismic and structural health monitoring is being installed in the city of Catania (Sicily, Italy). The 27 monitoring stations, specifically designed and assembled, equipped with a low-noise 3-axial MEMS accelerometer, are located in 23 high exposure and vulnerability buildings. In this paper we present the characteristics of the monitoring station and of the network. In case of strong seismic events, the system will provide shake maps to the emergency management centre, and will allow to assess the health conditions of the monitored buildings. The network is conceived to be further expandable over the whole historical city centre of the city of Catania.

We introduce the realization of the first European real-time urban seismic network based on Micro Electro-Mechanical Systems (MEMS) technology. The project is called Monitoring Earthquake through MEMS Sensors (MEMS) and encompass the installation of about 100 seismic station in the municipality of Acireale (Sicily, Italy). The stations, specifically designed and assembled, are equipped with a triaxial MEMS accelerometer, and gyroscope and GPS. In this paper we present the characteristics of the station and of the network. The main objective of the network is a rapid, post-earthquake disaster assessment through the automatic production of shake maps. The network also allow the implementation of an automatic recognition system for damage assessment from remotely piloted aircraft, and of a site-specific Earthquake Early Warning system.

The TOMO-ETNA experiment was planned in order to obtain a detailed geological and structural model of the continental and oceanic crust beneath Mt. Etna volcano and northeastern Sicily up to the Aeolian Islands (southern Italy), by integrating data from active and passive refraction and reflection seismic methodologies, magnetic and gravity surveys. This paper focuses on the marine activities performed within the experiment, which have been carried out in the Ionian and Tyrrhenian Seas, during three multidisciplinary oceanographic cruises, involving three research vessels (“Sarmiento de Gamboa”, “Galatea” and “Aegaeo”) belonging to different countries and institutions. During the offshore surveys about 9700 air-gun shots were produced to achieve a high-resolution seismic tomography through the wide-angle seismic refraction method, covering a total of nearly 2650 km of shooting tracks. To register ground motion, 27 ocean bottom seismometers were deployed, extending the inland seismic permanent network of the Istituto Nazionale di Geofisica e Vulcanologia and a temporary network installed for the experiment. A total of 1410 km of multi-channel seismic reflection profiles were acquired to image the subsurface of the area and to achieve a 2D velocity model for each profile. Multibeam sonar and sub bottom profiler data were also collected. Moreover, a total of 2020 km of magnetic and 680 km of gravity track lines were acquired to compile magnetic and gravity anomaly maps offshore Mt. Etna volcano. Here, high-resolution images of the seafloor, as well as sediment and rock samples, were also collected using a remotely operated vehicle.

Summary Several shallow submarines areas are characterized by considerable releases of hydrocarbon gases, which, during earthquakes or volcanic activity, may suddenly and violently occur. In some instances, changes in chemical and physical properties of gas emissions, which are generated by geothermal systems connected to the volcanoes’ plumbing system, are important precursors of volcanic activity and useful indices for the study of the geothermal field. Furthermore, some superficial structures such faults, landslide slopes or archaeological relics should be studied with such a high detail that geophysical and bathymetric surveys are unable to provide. In response to the needs increasingly felt of a completely customizable low cost tool for geological/geophysical/geochemical investigation of shallow submarine system, in the framework of the ROVER project, starting from an international project called OpenROV, is being implemented a micro-ROV for multidisciplinary environmental investigation. In this paper, we will describe the project progress, with particular reference to the first tests conducted in pool and in sea water, the geophysical/geochemical instrumentation of which will be equipped and the automatic control algorithms that are being developed for the semi-automatic navigation.