The Interreg IV Italia-Austria "SeismoSAT" Project: connecting Seismic Data Centers via satellite

Since 2002 the Istituto Nazionale di Oceanografia e di Geofisica Sperimentale - OGS in Udine (Italy), the Zentralanstalt für Meteorologie und Geodynamik (ZAMG) in Vienna (Austria), and the Agencija Republike Slovenije za okolje (ARSO) in Ljubljana (Slovenija) are using the Antelope software suite as the main tool for collecting, analyzing, archiving and exchanging seismic data in real time, initially in the framework of the EU Interreg IIIA project “Trans-national seismological networks in the South-Eastern Alps”. The data exchange has proved to be effective and very useful in case of seismic events near the borders between Italy, Austria and Slovenia, where the poor single national seismic networks coverage precluded a correct localization, while the usage of common data from the integrated networks improves considerably the overall reliability of real time seismic monitoring of the area. At the moment the data exchange between the seismic data centers relies on internet: this however is not an ideal condition for civil protection purposes, since internet reliability is poor. For this reason in 2012 the Protezione Civile della Provincia Autonoma di Bolzano in Bolzano (Italy) joined OGS, ZAMG and ARSO in the Interreg IV Italia-Austria Project “SeismoSAT” aimed in connecting the seismic data centers in real time via satellite. The general schema of the project, including first data bandwith estimates and a possible architecture will be illustrated

The AlpArray Seismic Network: A Large-Scale European Experiment to Image the Alpine Orogen

International audienceThe AlpArray programme is a multinational, European consortium to advance our understanding of orogenesis and its relationship to mantle dynamics, plate reorganizations , surface processes and seismic hazard in the Alps-Apennines-Carpathians-Dinarides orogenic system. The AlpArray Seismic Network has been deployed with contributions from 36 institutions from 11 countries to map physical properties of the lithosphere and astheno-sphere in 3D and thus to obtain new, high-resolution geophysical images of structures from the surface down to the base of the mantle transition zone. With over 600 broadband stations Electronic supplementary material The online version of this article (https ://doi. 1 3 operated for 2 years, this seismic experiment is one of the largest simultaneously operated seismological networks in the academic domain, employing hexagonal coverage with station spacing at less than 52 km. This dense and regularly spaced experiment is made possible by the coordinated coeval deployment of temporary stations from numerous national pools, including ocean-bottom seismometers, which were funded by different national agencies. They combine with permanent networks, which also required the cooperation of many different operators. Together these stations ultimately fill coverage gaps. Following a short overview of previous large-scale seismological experiments in the Alpine region, we here present the goals, construction, deployment, characteristics and data management of the AlpArray Seismic Network, which will provide data that is expected to be unprecedented in quality to image the complex Alpine mountains at depth

Arrival angles of teleseismic fundamental mode Rayleigh waves across the AlpArray

The dense AlpArray network allows studying seismic wave propagation with high spatial resolution. Here we introduce an array approach to measure arrival angles of teleseismic Rayleigh waves. The approach combines the advantages of phase correlation as in the two-station method with array beamforming to obtain the phase-velocity vector. 20 earthquakes from the first two years of the AlpArray project are selected, and spatial patterns of arrival-angle deviations across the AlpArray are shown in maps, depending on period and earthquake location. The cause of these intriguing spatial patterns is discussed. A simple wave-propagation modelling example using an isolated anomaly and a Gaussian beam solution suggests that much of the complexity can be explained as a result of wave interference after passing a structural anomaly along the wave paths. This indicates that arrival-angle information constitutes useful additional information on the Earth structure, beyond what is currently used in inversions

Ambient-noise tomography of the wider Vienna Basin region

We present a new 3-D shear-velocity model for the top 30 km of the crust in the wider Vienna Basin region based on surface waves extracted from ambient-noise cross-correlations. We use continuous seismic records of 63 broad-band stations of the AlpArray project to retrieve interstation Green’s functions from ambient-noise cross-correlations in the period range from 5 to 25 s. From these Green’s functions, we measure Rayleigh group traveltimes, utilizing all four components of the cross-correlation tensor, which are associated with Rayleigh waves (ZZ, RR, RZ and ZR), to exploit multiple measurements per station pair. A set of selection criteria is applied to ensure that we use high-quality recordings of fundamental Rayleigh modes. We regionalize the interstation group velocities in a 5 km × 5 km grid with an average path density of ∼20 paths per cell. From the resulting group-velocity maps, we extract local 1-D dispersion curves for each cell and invert all cells independently to retrieve the crustal shear-velocity structure of the study area. The resulting model provides a previously unachieved lateral resolution of seismic velocities in the region of ∼15 km. As major features, we image the Vienna Basin and Little Hungarian Plain as low-velocity anomalies, and the Bohemian Massif with high velocities. The edges of these features are marked with prominent velocity contrasts correlated with faults, such as the Alpine Front and Vienna Basin transfer fault system. The observed structures correlate well with surface geology, gravitational anomalies and the few known crystalline basement depths from boreholes. For depths larger than those reached by boreholes, the new model allows new insight into the complex structure of the Vienna Basin and surrounding areas, including deep low-velocity zones, which we image with previously unachieved detail. This model may be used in the future to interpret the deeper structures and tectonic evolution of the wider Vienna Basin region, evaluate natural resources, model wave propagation and improve earthquake locations, among others

The Interreg IV Italia-Austria "SeismoSAT" Project: connecting Seismic Data Centers via satellite

Since 2002 the Istituto Nazionale di Oceanografia e di Geofisica Sperimentale - OGS in Udine (Italy), the Zentralanstalt für Meteorologie und Geodynamik (ZAMG) in Vienna (Austria), and the Agencija Republike Slovenije za okolje (ARSO) in Ljubljana (Slovenija) are using the Antelope software suite as the main tool for collecting, analyzing, archiving and exchanging seismic data in real time, initially in the framework of the EU Interreg IIIA project “Trans-national seismological networks in the South-Eastern Alps”. The data exchange has proved to be effective and very useful in case of seismic events near the borders between Italy, Austria and Slovenia, where the poor single national seismic networks coverage precluded a correct localization, while the usage of common data from the integrated networks improves considerably the overall reliability of real time seismic monitoring of the area. At the moment the data exchange between the seismic data centers relies on internet: this however is not an ideal condition for civil protection purposes, since internet reliability is poor. For this reason in 2012 the Protezione Civile della Provincia Autonoma di Bolzano in Bolzano (Italy) joined OGS, ZAMG and ARSO in the Interreg IV Italia-Austria Project “SeismoSAT” aimed in connecting the seismic data centers in real time via satellite. The general schema of the project, including first data bandwith estimates and a possible architecture will be illustrated.PublishedVienna, Austria1.1. TTC - Monitoraggio sismico del territorio nazionaleope

The Interreg IV Italia-Austria "SeismoSAT" Project: connecting Seismic Data Centers via satellite

Since 2002 the Istituto Nazionale di Oceanografia e di Geofisica Sperimentale - OGS in Udine (Italy), the Zentralanstalt für Meteorologie und Geodynamik (ZAMG) in Vienna (Austria), and the Agencija Republike Slovenije za okolje (ARSO) in Ljubljana (Slovenija) are using the Antelope software suite as the main tool for collecting, analyzing, archiving and exchanging seismic data in real time, initially in the framework of the EU Interreg IIIA project “Trans-national seismological networks in the South-Eastern Alps”. The data exchange has proved to be effective and very useful in case of seismic events near the borders between Italy, Austria and Slovenia, where the poor single national seismic networks coverage precluded a correct localization, while the usage of common data from the integrated networks improves considerably the overall reliability of real time seismic monitoring of the area. At the moment the data exchange between the seismic data centers relies on internet: this however is not an ideal condition for civil protection purposes, since internet reliability is poor. For this reason in 2012 the Protezione Civile della Provincia Autonoma di Bolzano in Bolzano (Italy) joined OGS, ZAMG and ARSO in the Interreg IV Italia-Austria Project “SeismoSAT” aimed in connecting the seismic data centers in real time via satellite. The general schema of the project, including first data bandwith estimates and a possible architecture will be illustrated.PublishedVienna, Austria1.1. TTC - Monitoraggio sismico del territorio nazionaleope

The usage of Antelope for acquiring end exchanging data in South-Eastern Alps: present configuration and future perspectives

In the period 2002-2006 the Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS) in Udine (Italy), the Zentralanstalt für Meteorologie und Geodynamik (ZAMG) in Vienna (Austria), the Dipartimento di Geoscienze (DiG) of the Trieste University in Trieste (Italy), the Agencija Republike Slovenije za okolje (ARSO) in Ljubljana (Slovenia) and the Protezione Civile della Regione Autonoma Friuli Venezia Giulia (PCFVG) in Palmanova (Italy) were involved in the EU INTERREG IIIA project “Seismological Networks Without Frontiers in the Southeastern Alps”. ZAMG is involved in the EU INTERREG IIIA project “FASTLINK”, together with the Protezione Civile della Provincia autonoma di Bolzano (Italy) and the ETH of Zurigo (Swizerland). The commercial Antelope-software suite from BRTT (Boulder Real Time Technologies - www.brtt.com) has been chosen as the common basis for real time data exchange, rapid location of earthquakes and alerting. Each institute contributes to the seismological monitoring in the South-Eastern Alps by sharing data from its seismic network. Antelope is a powerful software suite that easily allows sharing data in real-time among several institutions by means of its module ‘orb2orb’. The current Antelope setup of all institutions involved in data acquisition, sharing and archiving is described, together with the future evolution of the project. The border region of Slovenia, Austria and NE Italy has experienced several destructive earthquakes in the past. Different seismic networks are operating in the area supporting monitoring, alerting and research. The example of recent strong earthquakes demonstrated that the integration of services provided by the neighboring networks is essential for a rapid and efficient intervention.PublishedMontpellier (France)1.1. TTC - Monitoraggio sismico del territorio nazionaleope

BSHAP seismic source characterization models for the Western Balkan region

This manuscript presents the seismic source characterization models that were developed and used for the Western Balkan region in the framework of Harmonization of Seismic Hazard Maps in the Western Balkan Countries Project (BSHAP II) funded by NATO-Science for Peace and Security Program. Relevant knowledge about the geological and seismotectonic structure of Western Balkans and surrounding region was collected and utilized along with the BSHAP focal mechanism database and the BSHAP earthquake catalogue (Markusic et al. in Bull Earthq Eng 14(2): 321-343, 2016. doi: 10.1007/s10518015- 9833-z) to delineate seismic source models for different purposes. The super zone model of large zones bounds the regions with similar seismotectonic characteristics and catalogue completeness levels and was used for calculating the regional b-value of the magnitude recurrence relationship. Additionally, two models of smaller zones that represent the epistemic uncertainty in source geometry, maximum magnitude and style-of-faulting, were developed to be employed in the two-stage (circular and elliptical) smoothing procedure. Sets of sensitivity analyses are performed to support final estimates of some models' parameters affecting the smoothed seismicity rate. The seismic source models and the logic-tree presented here are to be implemented in the probabilistic seismic hazard assessment for the seismic hazard maps of the Western Balkan region