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This study presents the results of an experimental investigation conducted on a 2:3 scale model of a two-story stone masonry building. We tested the model on the UniKORE L.E.D.A. lab shake table, simulating the Mw 6.3 earthquake ground motion that struck L’Aquila, Italy, on 6 April 2009, with progressively increasing peak acceleration levels. We installed a network of accelerometric sensors on the model to capture its structural behaviour under seismic excitation. Medium-to lower-cost MEMS accelerometers (classes A and B) were compared with traditional piezoelectric sensors commonly used in Structural Health Monitoring (SHM). The experiment assessed the structural performance and damage progression of masonry buildings subjected to realistic earthquake inputs. Additionally, the collected data provided valuable insights into the effectiveness of different sensor types and configurations in detecting key vibrational and failure patterns. All the sensors were able to accurately measure the dynamic response during seismic excitation. However, not all of them were suitable for Operational Modal Analysis (OMA) in noisy environments, where their self-noise represents a crucial factor. This suggests that the self-noise of MEMS accelerometers must be less than 1 µg/√Hz, or preferably below 0.5 µg/√Hz, to obtain good results from the OMA. Therefore, we recommend ultra-low-noise sensors for detecting differences in the structural behaviour before and after seismic events. Our findings provide valuable insights into the seismic vulnerability of masonry structures and the effectiveness of sensors in detecting damage. The management of buildings in earthquake-prone areas can benefit from these specifications.

We describe the first dense real-time urban seismic–accelerometric network in Italy, named OSU-CT, located in the historic center of Catania. The city lies in the region with the greatest danger, vulnerability, and earthquake exposure in the entire Italian territory. OSU-CT was planned and realized within the project called EWAS “an Early WArning System for cultural heritage”, aimed at the rapid assessment of earthquake-induced damage and the testing of an on-site earthquake early warning system. OSU-CT is mainly based on low-cost instrumentation realized ad hoc by using cutting-edge technologies and digital MEMS (micro-electro-mechanical systems) triaxial accelerometers with excellent resolution and low noise. Twenty of the forty scheduled stations have already been set up on the ground floor of significant historic public buildings. In order to assess the performance of an earthquake early warning (EEW) on-site system, we also installed wide-band velocimeters (ETL3D/5s) in three edifices chosen as test sites, which will be instrumented for a structural health monitoring (SHM). In addition to several laboratory and field validation tests on the developed instruments, an effective operational test of OSU-CT was the Mw 4.3 earthquake occurring on 23 December 2021, 16 km west, south-west of Catania. Peak ground accelerations (4.956 gal to 39.360 gal) recorded by the network allowed obtaining a first urban shakemap and determining a reliable distribution of ground motion in the historical center of the city, useful for the vulnerability studies of the historical edifices.

The InSEA project (“ In itiatives in S upporting the consolidation and enhancement of the E MSO research infrastructure consortium (ERIC) and related A ctivities”) has the objective, as the full name of the project indicates, to consolidate and strengthen the infrastructures concerning the EMSO (“European Multidisciplinary Seafloor and water column Observatory”) ERIC (European Research Infrastructure Consortium) and all those technical-scientific activities related to it. In particular, the project is upgrading localized and distributed marine infrastructures, laboratories, observatories and spatial measurement activities in Southern Italian seas to support those activities of surveys in fixed time series points of observation of EMSO ERIC. The project is developing according to six implementation Objectives of Research (OR) that involve four National research Institutions: INGV, ISPRA, OGS and Anton Dohrn Zoological Station of Naples. The paper illustrates with more details the relevant objectives of the InSEA project and its most significant implementation phases.

The Ionian Sea in southern Italy is at the center of active interaction and convergence between the Eurasian and African–Adriatic plates in the Mediterranean. This area is seismically active with instrumentally and/or historically recorded Mw>7.0 earthquakes, and it is affected by recently discovered long strike-slip faults across the active Calabrian accretionary wedge. Many mud volcanoes occur on top of the wedge. A recently discovered one (called the Bortoluzzi Mud Volcano or BMV) was surveyed during the Seismofaults 2017 cruise (May 2017). High-resolution bathymetric backscatter surveys, seismic reflection profiles, geochemical and earthquake data, and a gravity core are used here to geologically, geochemically, and geophysically characterize this structure. The BMV is a circular feature ≃22 m high and ≃1100 m in diameter with steep slopes (up to a dip of 22∘). It sits atop the Calabrian accretionary wedge and a system of flower-like oblique-slip faults that are probably seismically active as demonstrated by earthquake hypocentral and focal data. Geochemistry of water samples from the seawater column on top of the BMV shows a significant contamination of the bottom waters from saline (evaporite-type) CH4-dominated crustal-derived fluids similar to the fluids collected from a mud volcano located on the Calabria mainland over the same accretionary wedge. These results attest to the occurrence of open crustal pathways for fluids through the BMV down to at least the Messinian evaporites at about −3000 m. This evidence is also substantiated by helium isotope ratios and by comparison and contrast with different geochemical data from three seawater columns located over other active faults in the Ionian Sea area. One conclusion is that the BMV may be useful for tracking the seismic cycle of active faults through geochemical monitoring. Due to the widespread diffusion of mud volcanoes in seismically active settings, this study contributes to indicating a future path for the use of mud volcanoes in the monitoring and mitigation of natural hazards.