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Following the setting up of the Malta Seismic Network, new opportunities for research arise which go beyond the conventional monitoring of local and regional earthquakes. The new data is used to carry out site response studies as well as high-resolution subsurface studies such as velocity profiles and groundwater imaging of the aquifers below. These studies have significant importance for Malta, particularly because it is a small island country 15 km wide by 30 km long in the centre of the Mediterranean Sea (about 100 km south of Sicily, Italy). The network operated by the Seismic Monitoring and Research Group at the University of Malta is being exploited to maximize its full potential aiding the local Department of Civil Protection with earthquake monitoring and tsunami modelling and now the Energy and Water Agency with groundwater monitoring. We present the recent developments of the seismic network, examples of local earthquake recordings, earthquake catalogue and site response studies. In addition, we present SIGMA (Seismic Imaging of Groundwater for Maltese Aquifers), a new project aimed at imaging the spatial and temporal characteristics of aquifers across Malta – a first to cover a whole country that is completely surrounded by sea. The data set is derived from a combination of 13 stations, including those of the Malta Seismic Network and other temporary instruments spanning across the whole archipelago. We use auto/cross-correlation of noise recorded on the stations to extract information about the subsurface and track temporal and spatial changes in water content at different scales. These changes are compared to in situ borehole readings and meteorological parameters., peer-reviewed

The Sicily Channel, located on the north-central African plate foreland between Sicily, Tunis and Libya, is characterised by a seismically and volcanically active rift zone. This rift extends for more than 600 km in length offshore from the south of Sardinia to the south-east of Malta. Much of the observations we have today are either limited to the surface and the upper crust, or are broader and deeper from regional seismic tomography, missing important details about the lithospheric structure and dynamics. The project GEOMED (https://geomed-msca.eu) addresses this issue by processing all the seismic data available in the region in order to understand better the geodynamics of the Central Mediterranean. A recently compiled earthquake catalogue for the eastern part of the Sicily Channel Rift Zone (SCRZ) will be presented highlighting offshore active faults in the region, and new results from seismic tomography give an insight of what lies beneath. We measure seismic velocities from across the region using ambient seismic noise recorded on more than 50 stations located on Algeria, Italy (Lampedusa, Linosa, Pantelleria, Sardinia, Sicily), Libya, Malta, and Tunisia. The phase-velocity dispersion curves have periods ranging from 5 to 100 seconds and sample through the entire lithosphere. We find that slow and fast seismic velocities coincide with regional tectonic and topographic features. At short periods, Africa and Italy have slower velocities indicating these areas have thick continental crust in contrast to areas beneath Tyrrhenian and Ionian basins. The central area of the SCRZ has relatively faster velocities suggesting that there is a thinner crust. At longer periods the central area of SCRZ is characterised by slower velocities indicative of warmer temperatures than the surrounding. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 843696., peer-reviewed

Appropriate planning and deployment of a seismic network is a prerequisite to efficiently monitor seismic activity, determine the seismic source, and eventually contribute to the seismotectonic interpretation and seismic hazard assessment. The evaluation and effectiveness of a local network on the Maltese islands, recently extended by a further six seismic stations for one year, is presented. We investigate the new temporary network's data and site selection quality, utilizing spectral patterns in the seismic data and also evaluate the network's event location performance by relocating a number of recorded events. The results will be signifi cant for the future installation of permanent seismic stations on the Maltese islands., peer-reviewed

In Trieste, during the 35th General Assembly of the European Seismological Commission (ESC), the Department of Geosciences at the University of Malta was chosen to host the 36th General Assembly (Fig. 1). The city of Valletta won the bid among competition from three other European cities. The event took place at the Mediterranean Conference Centre (Fig. 2) from the 2–7 September 2018 and was preceded by a one-week Young Seismologists Training Course (YSTC; Fig. 3). The ESC is a commission within the International Association for Seismology and Physics of the Earth’s Interior, whose General Assembly takes place every two years. It is primarily a meeting ground for academics and researchers working in the field of seismology and related applications, including applied and social aspects of seismology, such as earthquake hazard and risk, earthquake engineering, education and awareness, and risk prevention., N/A

An international scientific conference organised by the Seismic Monitoring and Research Unit, Department of Geoscience, Faculty of Science, Department of Civil and Structural Engineering and Department of Construction and Property Management, Faculty of the Built Environment, University of Malta., Part of the SIMIT project: Integrated civil protection system for the Italo-Maltese cross-border area. Italia-Malta Programme – Cohesion Policy 2007-2013, This conference is one of the activities organised within the SIMIT strategic project (Integrated Cross-Border Italo-Maltese System of Civil Protection), Italia-Malta Operational Programme 2007 – 2013. SIMIT aims to establish a system of collaboration in Civil Protection procedures and data management between Sicilian and Maltese partners, so as to guarantee the safety and protection of the citizens and infrastructure of the cross-border area. It is led by the Department of Civil Protection of the Sicilian region, and has as other partners the Department of Civil Protection of Malta and the Universities of Palermo, Catania and Malta. SIMIT was launched in March 2013, and will come to a close in October 2015. Ever since the initial formulation of the project, it has been recognised that a state of national preparedness and correct strategies in the face of natural hazards cannot be truly effective without a sound scientific knowledge of the hazards and related risks. The University of Malta, together with colleagues from other Universities in the project, has been contributing mostly to the gathering and application of scientific knowledge, both in earthquake hazard as well as in building vulnerability. The issue of seismic hazard in the cross-border region has been identified as deserving foremost importance. South-East Sicily in particular has suffered on more than one occasion the effects of large devastating earthquakes. Malta, although fortunately more removed from the sources of such large earthquakes, has not been completely spared of their damaging effects. The drastic increase in the building density over recent decades has raised the level of awareness and concern of citizens and authorities about our vulnerability. These considerations have spurred scientists from the cross-border region to work together towards a deeper understanding of the underlying causes and nature of seismic and associated hazards, such as landslide and tsunami. The SIMIT project has provided us with the means of improving earthquake surveillance and analysis in the Sicily Channel and further afield in the Mediterranean, as well as with facilities to study the behaviour of our rocks and buildings during earthquake shaking. The role of the civil engineering community in this endeavour cannot be overstated, and this is reflected in the incorporation, from the beginning, of the civil engineering component in the SIMIT project. Constructing safer buildings is now accepted to be the major option towards human loss mitigation during strong earthquakes, and this project has provided us with a welcome opportunity for interaction between the two disciplines. Finally the role of the Civil Protection authorities must occupy a central position, as we recognize the importance of their prevention, coordination and intervention efforts, aided by the input of the scientific community. This conference brings together a diversity of geoscientists and engineers whose collaboration is the only way forward to tackling issues and strategies for risk mitigation. Moreover we welcome the contribution of participants from farther afield than the Central Mediterranean, so that their varied experience may enhance our efforts. We are proud to host the conference in the historic city of Valletta, in the heart of the Mediterranean, which also serves as a constant reminder of the responsibility of all regions to protect and conserve our collective heritage., peer-reviewed

Weak to moderate earthquakes in the Sicily Channel have until now been either poorly located or left undetected. The number of seismic stations operated by various networks: Italy (INGV), Tunisia (TT), and Libya (LNSN) have now improved considerably, however most of the seismicity occurs offshore, in the central part of the Channel, away from the mainland stations. Seismic data availability from island stations across the Channel has been limited or had intermittent transmission hindering proper real-time earthquake monitoring and hypocentre relocation. In order to strengthen the seismic monitoring of the Sicily Channel, in particular the central parts of the Channel, the Seismic Monitoring and Research Unit (SMRU), University of Malta, has, in the last year, been installing a permanent seismic network across the Maltese archipelago: the Malta Seismic Network (ML). Furthermore the SMRU has upgraded its IT facilities to run a virtual regional seismic network composed of the stations on Pantelleria and Lampedusa, together with all the currently publicly available stations in the region. Selected distant seismic stations found elsewhere in the Mediterranean and across the globe have also been incorporated in the system in order to enhance the overall performance of the monitoring and to detect potentially damaging regional earthquakes. Data acquisition and processing of the seismic networks are run by SeisComP. The new installations are part of the project SIMIT (B1-2.19/11) funded by the Italia-Malta Operational Programme 2007-2013. The new system allows the SMRU to rapidly perform more accurate hypocentre locations in the region, and issue automatic SMS alert for potentially felt events in the Sicily Channel detected by the network and for strong earthquakes elsewhere. Within the SIMIT project, the alert system will include civil protection departments in Malta and Sicily. We present the recent developments of the real and virtual seismic network, and discuss the performance of each of the new stations, the general operation of the SMRU, and the alert system. New web features soon available on the SMRU website will be presented., peer-reviewed

The establishment of an enhanced national seismic network for the Maltese islands, and ultimately for the Sicily Channel region, was carried out within the strategic project SIMIT (Costituzione di un Sis- tema Integrato di Protezione Civile Transfrontaliero Italo–Maltese) funded by the Italia–Malta Operational Programme. SIMIT was designed to work towards the establishment of an integrated system for the evaluation, forecasting, prevention and mitigation of losses from geological hazards affecting the Sicily Channel. The project was led by the regional Civil Protection Department (CPD) of Sicily and included the Civil Protection Department of Malta and Universities in the region, and therefore one of its important aspects was the raising and dissemination of the awareness about earthquake hazard and risk in this region. Although the knowledge about seismicity and seismic hazard in Sicily is quite advanced, the same cannot be said about the Maltese islands and other islands in the Sicily Channel. This is a problem that is common to island nations for which the seismicity affecting the countries occurs below the surrounding seas and presents problems in epicentral location, instrumental coverage, near–source effects, etc. Another problem affecting this area is the low–to–moderate level of seismic activity, and the very rare occurrence of large magnitude events in the region, making probabilistic analysis more difficult, and presenting a lack of historical and instrumental data on which to base seismological analyses., peer-reviewed

The Central Mediterranean is one of the most seismically active and tectonically dynamic regions in the Mediterranean characterised by a system of extension in the north (Appenines), a slab rollback in the centre (Calabria) and a rift zone in the south (Sicily Channel), all within a general convergent setting between the African and European plates. Unlike the northern regions of the Central Mediterranean (and others such as along the Hellenic subduction zone), earthquake monitoring within the Sicily Channel has, so far, been inadequate. During the last two years the Seismic Monitoring and Research Unit (University of Malta) has been upgrading its earthquake monitoring capabilities, with the addition of new broadband seismic stations and state-of-the-art real-time monitoring. The new setup will not only help to investigate better the regional seismicity within the Sicily Channel, but will also facilitate early warning of potentially felt earthquakes originating hundreds of kilometres away from Malta. This investment is part of the project SIMIT (B1-2.19/11) funded by the Italia-Malta Operational Programme 2007–2013., peer-reviewed

La Terra, mite ed ospitale per diecimila anni, da circa due secoli è entrata nell’Antropocene, una nuova epoca geologica che si distingue per l’impatto dell’uomo sul clima e sull’ambiente. Secondo Sandro Calvani (2013), è certo che viviamo per la prima volta in un sistema planetario di relazioni tra umanità e natura in cui l’umanità controlla tutte le altre variabili ed è responsabile di tutte le conseguenze. Il genere umano è in grado per la prima volta di distruggere o salvare il suo futuro. Per questi motivi, da alcuni anni, in Italia, sta crescendo l’interesse per la Geoetica (Peppoloni e Di Capua, 2012) che si occupa delle implicazioni etiche, sociologiche e culturali delle Scienze della Terra, ampliando le prospettive e le aspettative delle Geoscienze ed evidenziando il ruolo fondamentale svolto dagli studi geologici e geografci nel trovare soluzioni ai problemi pratici della vita dell’uomo, compatibilmente con la preservazione della natura e del Pianeta. Infatti, l’uomo costituisce sempre parte attiva anche nei fenomeni catastrofci in quanto può fungere da amplifcatore del danno e delle dinamiche naturali. D’altra parte, per quanto tali fenomeni risultino solo parzialmente prevedibili, comunque si può intervenire sui parametri del rischio dipendenti dall’antropizzazione quali la vulnerabilità e valore esposto che segnano il discrimine tra evento e calamità. Attraverso l’informazione e la conoscenza del rischio è, quindi, possibile contenere al minimo i danni, affnando le tecniche di previsione e prevenzione. Nell’ambito di ricerca che riguarda la percezione dei rischi naturali, si collocano storicamente gli studi di tipo geografco orientati all’approfondimento degli elementi di natura descrittiva e all’analisi del comportamento sociale di fronte al verifcarsi di rischi naturali generati da fonti assunte date ed esogene (Gatto e Saitta, 2009). In tale contesto, è stato somministrato un questionario agli studenti della secondaria di primo grado di Mottafollone, in provincia di Cosenza, nell’area del Pollino, che costituisce un’area sismicamente attiva, e nell’isola di Malta, che costituisce, invece, un’area di bassa-moderata pericolosità sismica in cui la consapevolezza del rischio sismico non è culturalmente solida. Le isole maltesi hanno, tuttavia, risentito storicamente di una serie di terremoti, i cui epicentri furono in Sicilia orientale, nel Canale di Sicilia o nell’Arco Ellenico. Alcuni di questi terremoti hanno prodotto notevoli danni., N/A

This book is part of the SIMIT project: Integrated civil protection system for the Italo-Maltese cross-border area. Specific topics regarding earthquakes is provided, particularly how earth movements are caused and safety precautions during seismic activity., peer-reviewed

The final target of the MONSOON project (MONitoraggio SOttOmariNo for environmental and energetic purposes) is to build up a prototype of a new generation of seafloor observatory for which specific technological developments in terms of power consumption reduction, new data logger and new sensors have been planned. The project is carried out in the main frame of the wide range of scientific and technological activities developed by EMSO Research Infrastructure (European Multidisciplinary Seafloor and water-column Observatory, www.emsoeu.org). The new seafloor observatory is planned to operate either in stand-alone and real-time modes. The latter is possible with the connection to a surface buoy able to 1) provide (via modem) an internet connection to the sea-floor system and 2) communicate with the sea-floor observatory. The observatory is planned to be deployed down to a water depth of 2000m, even in an extreme marine environment, with the presence of hydrothermal vents. All the newly developed components of the observatory have been planned and laboratory-tested. In cooperation with the University of Malta a special activity is carried out to find out technical solutions for the detection of body and surface seismic waves and for the integration of specific seismic sensors into the multidisciplinary seafloor observatory. The purpose of that activity is the integration of a seismic sensor (either a short period or a broad band seismometer) in the same data acquisition system that manages the whole observatory in order to make the observatory able to be used in studies and monitoring activities in the georisks field. After a successful laboratory testing activity, experiments in a selected, real environment are planned. [excerpt], peer-reviewed

The Central Mediterranean is a region of active tectonics characterised by the interaction of a number of varied and sometimes poorly understood processes. Superimposed on the convergent scenario of the African plate pushing northwestward, a NE-SW directed extensional regime is active in the Sicily Channel, expressed in the form of a seismically active east-west trending system of strike-slip lineaments and a series of pull-apart grabens. The offshore seismicity of the Sicily channel, generally limited to magnitudes below 4.5, is normally difficult to quantify precisely, due to poor station coverage, yet it is believed that its analysis will considerably improve our understanding of the processes affecting the region. We present recent improvements to real and virtual seismic networking in the Central Mediterranean, based at the Seismic Monitoring and Research Unit (SMRU), University of Malta. Within the project SIMIT (B1-2.19/11) funded by the Italia-Malta Operational Programme 2007-2013, earthquake monitoring on the Maltese Islands is being upgraded through the installation of a further two broadband stations, one of which will be on the smaller island of Gozo. A new network, ML (Malta Seismic Network), has been internationally registered with the FDSN. At the same time, the installation and implementation of SeisComP3 has enabled the setting up of a virtual, real-time Central Mediterranean network, made up of 18 stations in Southern Italy (including Sicily, Lampedusa and Pantelleria) belonging to the Istituto Nazionale di Geofisica e Vulcanologia, 3 stations in Tunisia (National Institute of Meteorology of Tunisia) and the 3 stations on the Maltese Islands. This will allow us to rapidly perform more accurate hypocentral locations in the region. The virtual network, which also incorporates a number of more distant stations, has been tuned to issue SMS alerts for potentially felt events in the Sicily Channel detected by the network, and for strong earthquakes elsewhere. Within the SIMIT project, the alert system will include Civil Protection departments in Malta and Sicily. Small magnitude earthquakes, especially those located to the south and south-east of the Maltese Islands, may still go undetected by the network. In this case, use is made of a single-station polarization analysis method (LESSLA) developed at SMRU. The integration of data from the above methods allows us to produce a more comprehensive seismicity map for the Sicily Channel, which will be interpreted in terms of the dynamics of the Sicily Channel Rift System., peer-reviewed

The continual operation of a permanent seismograph, now exceeding a couple of decades in some cases, naturally involves changes of hardware and software over time. Nonetheless, the long-term, consistent performance of the seismic station, and the good quality of its data, is very important for national seismic studies investigating the local seismicity, and also important for the international seismological community researching regional tectonics and deep Earth structures. Here we investigate the data availability and quality of the currently only seismic station on Malta (WDD) since its installation in 1995, and establish spectral patterns in the seismic data that may be influenced by diurnal variations, seasonal weather changes, and/or site-specific settings. The results are important for the future deployment of permanent seismic stations on the Maltese islands, and for the analysis of local seismic hazard and ground motion studies., peer-reviewed

Broadband seismic experiments over the last two decades have produced dense data coverage across Tibet. Yet, the mechanism of the India-Asia lithospheric convergence beneath it remains a puzzle, with even its basic features debated and with very different end-member models advocated today. We measured highly accurate Rayleigh- and Love-wave phase-velocity curves in broad period ranges (up to 5–200 s) for a few tens of pairs and groups of stations across Tibet, combining, in each case, hundreds to thousands of interstation measurements made with cross-correlation and waveform-inversion methods. Robust shear-velocity profiles were then determined by extensive series of nonlinear inversions of the data, designed to constrain the depth-dependent ranges of isotropic-average shear speeds and radial anisotropy. Temperature anomalies in the upper mantle were estimated from shear velocities using accurate petrophysical relationships. Our results reveal strong heterogeneity in the upper mantle beneath Tibet. Very large high-velocity anomalies in the upper mantle are consistent with the presence of underthrust (beneath southwestern Tibet) and subducted (beneath central and eastern Tibet) Indian lithosphere. The corresponding thermal anomalies match those estimated for subducted Indian lithosphere. In contrast to the Indian lithosphere, Tibetan lithosphere and asthenosphere display low-to-normal shear speeds; Tibetan lithosphere is thus warm and thin. Radial anisotropy in the upper mantle is weak in central and strong in northeastern Tibet, possibly reflecting asthenospheric flow above the subducting Indian lithospheric slab.

Ground motion at the site is influenced by source, propagation path, and local site conditions. One of the most important parameters describing ground motion during earthquakes is the Fourier-amplitude spectrum. Spectral parameter kappa is used to describe spectral amplitude decay at high frequencies. Over the last several decades, the researchers are consistent that near site attenuation kappa (site kappa) is affected primarily by site conditions. In this research spectral parameter kappa is estimated from the acceleration amplitude spectrum of shear waves (recordings of local earthquakes with magnitudes higher than 3, epicentral distances less than 150 km, and focal depths less than 30 km from four seismological stations situated in western part of Croatia – Northwestern External Dinarides) from the slope of the high-frequency part where the spectrum starts to decay rapidly to a noise floor. The spatial distribution of individual kappa’s is compared with azimuthal distribution of earthquake epicenters. Also, the obtained results are compared with Vs30 values (from geophysical measurements) and published coda-Q values for each station, as well as with isoseismal maps of stronger events in the investigated area and geological features. These results are significant for extending the knowledge of the attenuation of near-surface crust layers in the Nortwestern External Dinarides and providing additional information on the local earthquake parameters for updating seismic hazard maps of studied area.