Seismic-monitoring changes and the remote deployment of seismic stations (seismic spider) at Mount St. Helens, 2004-2005

Abstract. The Centro di Ricerche Sismologiche (CRS, Seismological Research Centre) of the Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS, Italian National Institute for Oceanography and Experimental Geophysics) in Udine (Italy) after the strong earthquake of magnitude M=6.4 occurred in 1976 in the Italian Friuli-Venezia Giulia region, started to operate the North-eastern Italy Seismic Network: it currently consists of 17 very sensitive broad band and 18 simpler short period seismic stations, all telemetered to and acquired in real time at the OGS-CRS data centre in Udine. Real time data exchange agreements in place with other Italian, Slovenian, Austrian and Swiss seismological institutes lead to a total number of about 100 seismic stations acquired in real time, which makes the OGS the reference institute for seismic monitoring of North-eastern Italy. The south-western edge of the OGS seismic network (Fig. 1) stands on the Po alluvial basin: earthquake localization and characterization in this area is affected by the presence of soft alluvial deposits. OGS ha already experience in running a local seismic network in high noise conditions making use of borehole installations in the case of the micro-seismicity monitoring of a local gas storage site for a private company. Following the ML = 5.9 earthquake that struck the Emilia region around Ferrara in Northern Italy on 20 May 2012 at 02:03:53 UTC, a cooperation of Istituto Nazionale di Geofisica e Vulcanologia, OGS, the Comune di Ferrara and the University of Ferrara lead to the reinstallation of a previously existing very broad band (VBB) borehole seismic station in Ferrara. The aim of the OGS intervention was on one hand to extend its real time seismic monitoring capabilities toward South-West, including Ferrara and its surroundings, and on the other hand to evaluate the seismic response at the site. We will describe improvements in running the North-eastern Italy Seismic Network, including details of the Ferrara VBB borehole station configuration and installation, with first results.

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METHODS OF SEISMIC DATA PROCESSING FOR SOLVING TASKS OF MONITORING OF FOREIGN TESTING LANDS

Проблеми створення, випробування, застосування та експлуатації складних інформаційних систем ◽

10.46972/2076-1546.2020.19.04 ◽

2021 ◽

pp. 31-41

Author(s):

Y. O. Gordienko ◽

A. O. Lotoshko ◽

O. O. Paplinskiy

Keyword(s):

Data Processing ◽

Seismic Waves ◽

Dynamic Properties ◽

International System ◽

Reference Signal ◽

Measurement Data ◽

Correlation Method ◽

Seismic Signal ◽

Seismic Monitoring ◽

Seismic Stations

The paper analyzes the methods of processing measurement data of the seismic observation method used in the International Seismic Monitoring System and the Main Center for Special Control of the State Space Agency of Ukraine to solve problems of monitoring nuclear tests at foreign test sites. The directions of improvement of known and development of new methods of processing of measuring data of seismic method of detection in the conditions of presence and absence of a priori information on the form of a seismic signal are defined. If the form of the expected seismic signal is known, then the monitoring of foreign test sites by the seismic grouping system can be realized by supplementing the method of controlled directional reception with a correlation scheme of measurement data processing. In the absence of information on the shape of the seismic signal, the monitoring of the test site is carried out by dividing the group into two subgroups, followed by the cross-correlation method between the original samples of each subgroup. For a network of three-component stations, if there is information about the shape of the expected seismic signal, the method of comparison with the reference signal is used. In the absence of reference signals, monitoring is implemented using system discriminant, which takes into account the kinetic and dynamic properties of the expected signal with a cell from a given area. Possibilities of application of seismic stations of the International system of seismic monitoring are analyzed, use of measuring data which for the decision of problems of monitoring of foreign landfills allows to reduce time of definition of parameters of a seismic event essentially. A feature of the signals registered by seismic stations of the International System is the presence of types of seismic waves characteristic of events with cells in the near zone. Implementation of monitoring of test sites is possible by taking into account the polarization and dynamic properties of seismic waves. The implementation of the proposed approaches will increase the efficiency of solving the problem of detecting nuclear explosions at foreign test sites.

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The national seismic network for the Maltese islands: Update 2021

10.5194/egusphere-egu21-8510 ◽

2021 ◽

Author(s):

Pauline Galea ◽

Matthew Agius ◽

George Bozionelos ◽

Sebastiano D'Amico ◽

Daniela Farrugia

Keyword(s):

Real Time ◽

Site Response ◽

Seismic Monitoring ◽

Seismic Network ◽

Local Network ◽

Time Data ◽

African Plate ◽

Seismic Stations ◽

Maltese Islands ◽

Sicily Channel

The Maltese islands are a small country 15 km wide by 30 km long located about 100 km south of Sicily, Italy. Since 2015 Malta has set up a national seismic network. The primary aim of this network is to monitor in real-time and to locate more accurately the seismicity close to the islands and the seismicity in the Sicily Channel, offshore between Sicily, Tunisia and Libya. This Channel presents a range of interesting and complex tectonic processes that have developed in response to various regional stress fields mainly as a result of the collision between the African plate with Europe. The Maltese islands are known to have been affected by a number of earthquakes originating in the Channel, with some of these events estimated to be very close to the islands.The seismotectonic characteristics of the Sicily channel, particularly south of the Maltese islands, is not well understood. This situation is being partially addressed through an increase in the number of seismic stations on the Maltese archipelago. The Malta Seismic Network (FDSN code ML), managed by the Seismic Monitoring and Research Group, within the Department of Geosciences, University of Malta, currently comprises 8 broadband, 3-component stations over an area slightly exceeding 300 km2. We present a technical description of the MSN including quality control tests such as spectral analysis (Power Spectral Density and HVSR), station orientations and timings as well as examples of local and regional earthquakes recorded on the network. We describe the upgrades to real-time data transmission and archiving, and automated epicentre location for continuous seismic monitoring using the local network amalgamated with a virtual seismic network to monitor the seismicity in the extended Mediterranean region. Such a dense national network, besides improving epicentral location in the Sicily Channel, is providing valuable information on microearthquake activity known to occur in close proximity to the islands, which has been very difficult to study in the past. It also provides an important tool for analysing site response and site amplification related to underlying geology, which constitutes a major component of seismic hazard analysis on the islands. Furthermore, the increase in seismic stations to the seismic monitoring system provides more robust earthquake estimates for the tsunami monitoring/simulation system.Funding for stations was provided by Interreg Italia-Malta projects (SIMIT and SIMIT-THARSY, Codes B1-2.19/11 and C1-3.2-57) and by Transport Malta.

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NORTH-EAST OF RUSSIA

Zemletriaseniia Severnoi Evrazii [Earthquakes in Northern Eurasia] ◽

10.35540/1818-6254.2019.22.18 ◽

2019 ◽

pp. 214-223 ◽

Cited By ~ 2

Author(s):

E. Alyeshina ◽

S. Kurtkin ◽

L. Karpenko ◽

B. Sedov

Keyword(s):

Bering Sea ◽

Seismic Energy ◽

Seismic Monitoring ◽

Magadan Oblast ◽

Monitoring Equipment ◽

Seismic Stations ◽

North East ◽

The North ◽

Border Areas

The seismic monitoring results of Magadan Oblast, Chukotka Autonomous Okrug, and adjacent sea shelfs (of Okhotsk, Chukchi, Bering, and East Siberian seas) are analyzed. The information about 14 digital seismic stations, as well as monitoring equipment types and parameters, is given. The maps of earthquakes energy representativeness, seismic stations, and epicenters are presented. The distributions of earthquakes number by energy classes and the total amount of seismic energy across six regions and border areas of North East are provided. The catalog includes information about 252 events with energy classes КR from 5.4 to 13.8. The earthquake epicenters of the Kolyma region are marked on the tectonic zoning scheme of Magadan Oblast. All earthquakes in North-East of Russia are spatially associated with the major seismogenic belts: the Chersky, the North Okhotsk and the Trans-Bering Sea

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Evolution and strengthening of the Calabrian Regional Seismic Network

Advances in Geosciences ◽

10.5194/adgeo-36-11-2013 ◽

2013 ◽

Vol 36 ◽

pp. 11-16 ◽

Cited By ~ 5

Author(s):

A. D'Alessandro ◽

A. Gervasi ◽

I. Guerra

Keyword(s):

Seismic Hazard ◽

Small Area ◽

Seismic Monitoring ◽

Seismic Network ◽

Individual Contribution ◽

Seismic Stations ◽

The Past ◽

Network Evaluation ◽

The Individual

Abstract. The Calabrian Arc is an area of high seismic hazard, in the past often affected by destructive earthquakes. The seismicity of the Calabrian region is monitored by the Italian National Seismic Network integrated by the Calabrian Regional one and, in the last three years, by the Pollino temporary array. We have applied the Seismic Network Evaluation through Simulation to assess the individual contribution of each network in locating earthquakes with epicentres in the Calabrian region and surrounding. We shows that the Calabrian Regional Seismic Network greatly improves the quality of the coverage in almost the Calabria territory except in the Crotone Basin, in the Serre and in the offshore areas. We show that the contribution of the Pollino temporary array is instead restricted to a very small area centred on the Pollino Chain. Due to the presence in the Serre of important seismogenic volumes, which in the past have generated destructive earthquakes, it would be opportune to add at least several seismic stations in this area and surrounding to improve the seismic monitoring.

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TO STUDY THE POSSIBILITIES OF USING THE SEISMOLOGICAL NETWORK OF THE ALTAI-SAYAN REGION FOR REGIME VIBRO-SEISMIC OBSERVATIONS

Interexpo GEO-Siberia ◽

10.33764/2618-981x-2021-2-2-280-288 ◽

2021 ◽

Vol 2 (2) ◽

pp. 280-288

Author(s):

Victor M. Solovyev ◽

Aleksandr F. Emanov ◽

Semen A. Elagin ◽

Natalya А. Galyova

Keyword(s):

Seismic Monitoring ◽

Vibration Monitoring ◽

Effective Range ◽

Radiation Characteristics ◽

Seismic Stations ◽

The Real ◽

Sayan Region ◽

Special Programs ◽

Seismic Background ◽

Seismological Network

The results of experiments on the study of the radiation characteristics of powerful vibrators and reception conditions at a number of seismic stations in the Altai-Sayan region in the range of distances of 50-450 kilometers in the problem of selecting points for active vibro-seismic monitoring are presented. It is shown that the real effective range of the CV-40 vibrator can be significantly increased by using multiple and semi-multiple harmonics. A method for assessing the applicability of stations for vibration monitoring using special programs for assessing the seismic background and seismic resonances within the boundaries of the location of seismic stations is proposed and tested.

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SISMIKO: emergency network deployment and data sharing for the 2016 central Italy seismic sequence

Annals of Geophysics ◽

10.4401/ag-7212 ◽

2016 ◽

Vol 59 ◽

Author(s):

Milena Moretti ◽

Silvia Pondrelli ◽

Lucia Margheriti ◽

Luigi Abruzzese ◽

Mario Anselmi ◽

...

Keyword(s):

Seismic Station ◽

Central Italy ◽

Strong Motion ◽

Monitoring Network ◽

Seismic Monitoring ◽

Seismic Network ◽

Seismic Sequence ◽

British Geological Survey ◽

Epicentral Area ◽

Seismic Stations

At 01:36 UTC (03:36 local time) on August 24th 2016, an earthquake Mw 6.0 struck an extensive sector of the central Apennines (coordinates: latitude 42.70° N, longitude 13.23° E, 8.0 km depth). The earthquake caused about 300 casualties and severe damage to the historical buildings and economic activity in an area located near the borders of the Umbria, Lazio, Abruzzo and Marche regions. The Istituto Nazionale di Geofisica e Vulcanologia (INGV) located in few minutes the hypocenter near Accumoli, a small town in the province of Rieti. In the hours after the quake, dozens of events were recorded by the National Seismic Network (Rete Sismica Nazionale, RSN) of the INGV, many of which had a ML > 3.0. The density and coverage of the RSN in the epicentral area meant the epicenter and magnitude of the main event and subsequent shocks that followed it in the early hours of the seismic sequence were well constrained. However, in order to better constrain the localizations of the aftershock hypocenters, especially the depths, a denser seismic monitoring network was needed. Just after the mainshock, SISMIKO, the coordinating body of the emergency seismic network at INGV, was activated in order to install a temporary seismic network integrated with the existing permanent network in the epicentral area. From August the 24th to the 30th, SISMIKO deployed eighteen seismic stations, generally six components (equipped with both velocimeter and accelerometer), with thirteen of the seismic station transmitting in real-time to the INGV seismic monitoring room in Rome. The design and geometry of the temporary network was decided in consolation with other groups who were deploying seismic stations in the region, namely EMERSITO (a group studying site-effects), and the emergency Italian strong motion network (RAN) managed by the National Civil Protection Department (DPC). Further 25 BB temporary seismic stations were deployed by colleagues of the British Geological Survey (BGS) and the School of Geosciences, University of Edinburgh in collaboration with INGV. All data acquired from SISMIKO stations, are quickly available at the European Integrated Data Archive (EIDA). The data acquired by the SISMIKO stations were included in the preliminary analysis that was performed by the Bollettino Sismico Italiano (BSI), the Centro Nazionale Terremoti (CNT) staff working in Ancona, and the INGV-MI, described below.

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