L’objectif de cette table ronde de haut niveau est de souligner le rôle de la francophonie et le multilinguisme comme facilitateur des discussions internationales. Des ambassadeurs rompus à ces échanges apporteront leur ressenti sur le sujet.
The European Union (EU) remains a staunch supporter of the CTBT and its Organisation, both politically and financially. Promoting the universalisation and entry into force of the CTBT is a top priority for the EU, in line with its non-proliferation and disarmament policies and objectives.
In the framework of the EU Strategy against the Proliferation of Weapons of Mass Destruction, the EU...
To be updated
[This panel discusses the mutual benefits between the CTBTO and Arabic-speaking countries. For many local experts engaging in the operation of IMS stations and serving at the National Data Centres (NDC) having the training and capacity-building materials in Arabic is beneficial. An excellent example was set with the NDC training for Arabic-speaking NDCs that was held in January...
English title: Regional capacity building for IMS station managers and operators in French-speaking countries in Africa
This panel discusses operational strategies and challenges faced by managers and operators of International Monitoring System stations in French-speaking countries in Africa. The objective is to strengthen the capabilities of operators in order overcome the challenges...
Disasters affect populations on a global scale. The Latin American and the Caribbean (LAC) region, is frequently impacted by large earthquakes, tsunamis, volcanic eruptions, and extreme weather events (drought and tropical storms). The raising awareness and concern about the need for disaster risk mitigation, highlights the necessity for operating multi-technology platforms to understand...
We present a recent example for the civil and scientific application of International Monitoring System (IMS) hydroacoustic data. On 24 April 2022, IMS stations detected a cluster of impulsive, seismoacoustic events in the South Sandwich Arc, a volcanically active chain of remote islands and seamounts in the southern Atlantic Ocean. Preliminary results from automated and interactive analysis...
One of the sources of acoustic signals is underwater volcanic eruptions. Climatic phase of such underwater eruptions results in an ash cloud being ejected into the stratosphere thus generating infrasound signals while at the same time generating acoustic signals. The active volcano in Hunga Tonga-Hunga Ha'apai (HTHH) one of the Tonga Island groups erupted violently on 15 January 2022...
Indonesia is a relatively high seismic activity region and one of the most active areas is the West Papua. TOAST is a software used for tsunami modeling simulations that can provide results quickly and in real time. Analysis of the impact of the tsunami using TOAST shows that based on the earthquake scenario on 10 October 2002 for the magnitudes varying from 7.0 to 8.0, the highest tsunami...
Anthropogenic noise pollution may mask natural sounds, which are fundamental to survival and reproduction of wildlife, especially for marine cetaceans as they are highly dependent on underwater sounds for basic life functions. In the 21st century, shipping in the ocean has increased significantly and causes low frequency (10–100 Hz) noise which affects or hinders vital communication of large...
Old fashion earthquake early warnings are changing in a new era in the shadow of Earthquake Preparedness Alert (EPA), which instead of noticing only a few seconds, issues a few days in advance. Still, EPAs need more efforts for being used in the public sector, but already they are used in oil and gas, mining in California and Nevada. Since September 2020, the generated models in project...
Long term observations using hydrophones installed by the CTBTO in the Indian Ocean, suggest that noise levels increased from 2002 to around 2012. Since then they have been decreasing. While the increase in noise levels was related to growth in ship traffic, the reasons for the decrease are not known. This paper investigates the reasons for the decrease in two steps. The first step builds an...
Scientific data shows that glaciers are melting due to Climate Change driven by global warming with some results showing an impact in the amount of seismic activity. If glaciers thawed, the enormous weight bearing down on the Earth's crust is reduced, experiencing what geologists refer to as a “post-glacial rebound." This process might reactivate faults and lift pressure on the subterranean...
The International Monitoring System (IMS), installed and maintained by the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) with the support of States Signatories, is a global system of monitoring stations composed of four complementary technologies: seismic, hydroacoustic, infrasound and radionuclide. One of the IMS radionuclide stations is located in Spitzbergen, a place where,...
There is a heated debate in the scientific community about possible effects of changes on the planet's surface due to global warming, frequency and magnitude of earthquakes, and tsunamis triggered by earthquakes. Some studies point to seasonal modulations of deep slow slip and earthquakes in the main thrust of the Himalayas or increased risks at coastlines. One aspect that everyone seems to...
The activity of the subduction zone in the south of Java island has been generating severe earthquakes and tsunami events in the past. This natural disaster made the southern region of Java, including the Yogyakarta special region (DIY), prone to incoming tsunamis. Kalurahan Glagah, a village in the south part of DIY, is one of 1,013 villages in Indonesia that has a high tsunami vulnerability,...
Seismic sensors have traditionally been largely restricted to on-land installations, yet the oceans comprise roughly 70% of the Earth's surface. Coupled with heterogeneous distribution of seismicity, this results in many regions being poorly sampled for Earth model development, and poorly monitored for detection of natural and anthropogenic seismic sources. To mitigate this deficiency,...
International Monitoring System hydrophone stations are useful for the monitoring of submarine volcanic activity, especially in the western Pacific Ocean. Therefore, we started to routinely analyse the signals of triplet H11S, located off the coast of Wake Island, from July 2022 onwards. The SeedLink server of the Incorporated Research Institutions for Seismology (IRIS) provides the data; the...
Data collected by the International Monitoring System (IMS) represent four complementary technologies: seismic, hydroacoustic, infrasound and radionuclide. The main objective of acquiring IMS data is to detect and identify nuclear explosions on land, in the oceans, and in the atmosphere. However, the data are also extremely valuable for scientific studies e.g., to investigate the migration...
The eruption of the Hunga-Tonga-Hunga-Ha’apai volcano on 15 January 2022 was the largest recorded since the eruption of Krakatoa in 1883. The eruption triggered tsunami waves of up to 15m which struck the west coast of Tongatapu, ‘Eua and Ha’apai.
In this work we analyse data of this event. With a magnitude of mb 4.2 at 04:14:59 UTC, the eruption was detected by the three International...
The main objective of this project is to be able of identifying Paleo tsunamis and climate change. Using heavy metals deposits and calcium ratio, more specifics strontium. Our islands during time have been affected by a lot of earthquakes, leaving an enormous possibility of being affected by tsunamis, more of them, historically. Using strontium and calcium ratio we will be able to detect where...
Time-space variations of infrasound source locations from 2019 to 2021 were studied using a combination of two local arrays in the Lützow-Holm Bay (LHB), Antarctica. The local arrays deployed at two outcrops clearly detected temporal variations in frequency content as well as propagating directions during the three years. A large number of infrasound sources were detected and many of them...
Crustal attenuation structures obtained at high frequencies (>1 Hz) are important for seismic risk assessment and geodynamics studies in stable continents. However, it is difficult to infer attenuation in low seismicity regions using body and surface waves. In this study, we explore the potential of using seismic T phases to constrain the crustal attenuation. We analysed the characteristics of...
IDC data of radioactivity concentration of natural radionuclides in particulate matter collected at THP65 station have been studied their behaviors over a year. A significant difference of radioactivity concentrations of Pb-212F and Be-7 between wet and dry seasons has been found. North-east and south-west monsoons occurring on dry and wet seasons have been discussed their impacts on level of...
Simulations of a 1 to 2 km comet striking Earth on solid ground and on ocean waters have been conducted. Models include hydrostatic equilibrium profiles of temperature, pressure, and densities for atmosphere and ocean, in order to accurately predict impact consequences. Phase changes, such as melting and vaporization, combined with the material’s tensile, shear, and compressive strength...
Recently, some efforts have been made to apply the Boundary Element Method (BEM) to propagation problems in shallow waters, motivated by its neat mathematical formulation and the fact that, unlike other 3-D methods, only 2-D boundary integration is required. However, its chances of becoming a real competitor in the area are undermined by the large sizes of the discretized computational...
This is the first study after the signature of the tsunami warning agreement between the CTBTO and Madagascar in 2019. On 2nd of August 2019 12:03:23 UTC, an earthquake of magnitude 7 occurred south-west of Sumatra Indonesia and generated a local tsunami warning. The goal of this project is to monitor tsunami events using International Monitoring System seismic stations, then to simulate an...
The earthquake swarm accompanying the January 2022 Hunga Tonga-Hunga Ha’apai (HTHH) volcanic eruption includes many post-eruptive moderate magnitude seismic events and presents the unique opportunity to use remote monitoring methods to characterize and compare seismic activity to other historical caldera-forming eruptions. We compute improved epicentroid locations, magnitudes, and regional...
The eastern Mediterranean Basin was always the main trade route and cultural exchange between the old-world continents. Being centered in the middle of the three continents, the region is often referred to as the cradle of civilization. Meanwhile, it has suffered several catastrophic events, including earthquakes and Tsunamis. Due to its populated coasts, the possibility to record damage and...
The Arctic Ocean is rapidly warming. The hydroacoustic environment will be impacted by the changing thermohaline structure, increased marine traffic, changes in sea ice coverage, and possible increases in microseism/storm noise. This will inevitably lead to obsolescence for today’s ocean acoustic models. The only sophisticated way to make predictions is using decadal to centennial integrations...
The hydroacoustic International Monitoring System (IMS) network was designed to detect underwater nuclear explosions. Two types of stations belong to this network. Six of them record signals with hydrophone triplets placed in the Sound Fixing and Ranging (SOFAR) channel. Remaining five are T phase, seismic stations which detect hydroacoustic signal converted to seismic wave at a steep shore...
In support of the Comprehensive Nuclear-Test-Ban Treaty, the International Monitoring System (IMS) has implemented a set of deep water open ocean hydroacoustic stations for monitoring (detecting and localization) any nuclear tests. As acoustic propagation satisfies the acoustic wave equation sound is subject to three-dimensional effects (refraction, diffraction, reflections) when in the...
Ice avalanches constitute severe natural hazards, threatening human lives and infrastructures, and are expected to increase with ongoing climate change and population pressure forcing settlements into exposed terrain. In Europe, costly monitoring programs have also highlighted changing glacial hazards. Consequently, monitoring and warning systems, which help mitigate the threat and impact of...
The entry meteoroids and meteorites into the earth's atmosphere is a powerful source of infrasonic waves. The generated infrasound can be recorded at the ground and, using an array of sensors, characterized in terms of wave parameters, indicative of the source and its position. This study presents the integrated analysis of ~15 small fireball events based both on images of the all-sky cameras...
Bangladesh, a major part of the Bengal Basin, is an earthquake prone country due to its location at the junction of two major tectonic plates. The complicated geology of this basin is responsible for occurring several major and minor earthquakes in Bangladesh and its adjacent areas. The consequence of the earthquake and other natural disasters would be devastating for the country and its...
Detecting and notifying ongoing volcanic eruptions is crucial in supporting the Volcanic Ash Advisory Centres. However, local monitoring systems are missing at many active volcanoes. Long range infrasound monitoring, potentially able to detect and notify volcanic explosive events, might provide useful information. Indeed, many studies have already highlighted the utility of long range...
The location of the Northern Caucasus Geophysical Observatory of the Institute of Physics of the Earth, Russian Academy of Sciences (IPE RAS) in the immediate vicinity of the magma chamber of the Elbrus volcano makes it possible to obtain unique data on the structure and dynamics of the thermal field in its vicinity. A precision temperature observation system was developed at the IPE RAS some...
Aerodynamic infrasonic signals generated by large wind turbines can be detected by highly sensitive micro-barometers showing spectral peaks at the blade passing harmonics, which are above the background noise level. As infrasound is one of the four verification technologies for the compliances with the Comprehensive Nuclear-Test-Ban Treaty, decreases in detection capability for dedicated...
Everyday waveform data is detected and recorded by the seismic, hydroacoustic and infrasound stations (SHI) of the International Monitoring System produced by different sources coming from the earth, the oceans, and the atmosphere. In this study, signals of interest are the ones from volcanic sources, which can be put to wider civil and scientific use, from helping to save lives in case of...
Past earthquakes in the Banggai area were not widely reported. Lack of information on the source mechanism and the tsunami made it difficult to obtain a complete picture of the disaster events. The earthquake and tsunami on May 4, 2000 is one example. The tsunami earthquake that occurred, although very local in nature, had quite an impact in some locations. However, generating mechanism...
Myanmar is exposed to multiple natural disasters including cyclones, earthquakes, tsunamis etc. Myanmar has signed tsunami warning agreements with CTBTO. Myanmar can access IMS database and IDC products. These data together with national natural disaster monitoring means will be used to identify disaster prone areas of the country. Creating public knowledge about disaster prone areas and the...
Surface ocean currents are important maritime weather parameters because they influence both human activity and the global climate. In Indonesia, real time observations of surface ocean currents are currently made using HF-Radar installed in two locations, one of which is the Flores Sea. Because observational data is still scarce, efforts to provide surface ocean current data are required. One...
In the months following the Fukushima Daiichi nuclear power plant accident, the IMS radionuclide stations observed elevated concentrations of anthropogenic radionuclides throughout the northern hemisphere. These data are available for scientific research through the virtual Data Exploitation Centre (vDEC) after signing a cost-free confidentiality agreement with the CTBTO. Part of these...
The Instituto Geofísico of the Escuela Politécnica Nacional (IGEPN) is in charge of the monitoring and study of seismic and volcanic activity in the Ecuadorean territory. The networks include monitoring seismic, volcanic and geodetic networks with 105 seismic stations, 11 infrasound sensors, 67 strong motion sensors, 65 GPS of high accuracy and more than 56 stations for lahar detection, gas...
With support from the U.S. Department of Energy, Lawrence Livermore National Laboratory and the Incorporated Research Institutions for Seismology are collaborating with seismic monitoring centers in the Caucasus and Central Asia to expand national seismic networks through the installation of permanent broadband seismic stations. The main goal of the project is to improve regional network...
Wind turbines emit vibrations due to the rotation of the blades and the movement of the tower. Vibrations radiated from wind turbines are known to interfere with operational seismoacoustic monitoring of natural and induced seismicity. Additionally, the contribution of such vibrations to the ambient seismoacoustic noise field can significantly hinder the performance of sensitive optical...
Understanding and predicting seismoacoustic waveforms may be a real conundrum, depending on the complexity of the source term, but also on the geological features a wavefield is propagating through. Transmission of elastic energy (i.e. coupling) between the solid Earth and fluid layers (atmosphere, ocean) can bring a wealth of information about the characteristics of a source, but may be...
The 15 January 2022 eruption of the Hunga volcano (Tonga) generated a rich spectrum of waves, some of which achieved global propagation. Among numerous platforms monitoring the event, two stratospheric balloons flying over the tropical Pacific provided unique observations of infrasonic wave arrivals, detecting five complete revolutions. Combined with ground measurements from the infrasound...
Data from the IMS hydroacoustic, infrasound and seismic station networks empowers civil and scientific applications in climate knowledge generation and ocean monitoring activities across the world. Meanwhile, the value of science-informed, evidence-based policy making has gained wide recognition for providing robustness, clarity and practicality in driving the global sustainability agenda and...
The CTBT is considered to be a global instrument for the enhancement of international peace and security through the banning of nuclear weapons tests and constraining further development of existing nuclear weapons, on the other hand, the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) was established to prevent the proliferation of nuclear science and technology in all its...
The PUFF Model is a volcanic ash dispersion model used in Indonesia to help predict the distribution of volcanic ash for aviation safety purposes. This model uses the Lagrangian method taking into account wind, diffusion, and gravity parameters. The eruption of Mount Tonga on 15 January 2022 with a volcanic explosivity index (VEI) of 5 which exceeded Galunggung 1982 and Kelud 2014 is an...
The Hunga Tonga - Hunga Ha’apai (HTHH) eruption of 15 January 2022 was an exceptional event by the period, magnitude, and duration of propagation of the atmospheric waves it generated, circling the globe multiple times. Even though several volcanic eruptions in the past 150 years era of scientific instrumentation generated notable barometric disturbances, the HTHH eruption is comparable only...
On January 4, 2018, two earthquakes reported by the population were recorded in the northern region of Guatemala. These were characterized with the National Seismological Network (RSN), however another thirty-nine earthquakes of smaller magnitude could only be recorded by the Auxiliary Seismic Station APG (AS-037) due to the high standards that its facility meets for its use in monitoring of...
Volcanic ash cause airports to alter or close their operations when it was detected around the airport and the flight routes. Bali airport is one of the busiest airports in Indonesia. Unfortunately, it is surrounded by three active volcanoes which have recently erupted and spewed volcanic ash. Even though volcanic ash movements can be predicted, these events always have the effect of surprises...
The future of the CTBT verification system – opportunities for science and technology
- Presentation and discussion on gaps in science and technology
- Challenges - the NDC perspective
During this side-event we would like to discuss the future of the CTBT verification system. The development and implementation have been ongoing for 26 years, and the system is ninety per cent in...
Decades ago new opportunities in seismology were opened by the development of broadband seismic sensors with feedback. The three defining characteristics of these instruments were the bandwidth extension to longer periods, a much lower intrinsic noise and a higher dynamic range. However, the goal of further extending their bandwidth to frequencies above 100 Hz has proven elusive because these...
Nyepi is a rare activity in the world that only exists in Bali, where all human outdoor activities stop for a day. This study used Nyepi to measure its impact on ambient noise in Denpasar, the capital of Bali province. We used broadband and period seismometer, which operates 24 hours a day, to measure the difference before, during, and after Nyepi. Results of processing signal data using...
Hyperion Technology Group, Inc., along with the National Center for Physical Acoustics at the University of Mississippi, USA (NCPA ), has been developing an integrated calibration system for its line of infrasound sensors. This technology will allow self-calibration of the infrasound sensor in the field using existing installed equipment. While currently verified as an add-on for existing...
An on-site inspection (OSI) is a complex forensic investigation that requires a systematic approach that considers the operational, technical and time constraints specified in the Treaty. The information led inspection team functionality (ITF) and field team functionality (FTF) are comprehensive and systematic concepts that serve as essential guidance for the inspection team to conduct its...
The International Monitoring Systems (IMS) draft operational manuals for waveform stations require that IMS stations be calibrated regularly. Since 2012, the Provisional Technical Secretariat (PTS) had relied mostly on electrical calibration to meet that requirement. However electrical calibration has inherent challenges (no traceability, integration and sustainment issues, high operating...
The traceable calibration of seismometers is research work within the European research project (InfraAUV), which is part of the EMPIR programme. In this project, novel in-laboratory and on-site calibration procedures for seismometers are developed. The in-laboratory calibrations are carried out using electrodynamic shakers to excite sinusoidal vibrations. These excitations are measured by...
This poster presents the recent development and preliminary results of a compact laser refractometer based on a dual Fabry-Perot scheme at 1550 nm for dynamic infrasound pressure measurements. The measurement of the beat frequency between two lasers slaved to two Fabry-Perot cavities allows to follow the variation of the refractive index of the air, and thus to estimate the pressure inside the...
Conducting an on-site inspection (OSI) requires a large variety of resources, i.e. human, financial, technical, etc. The preparation of human resources is a challenge due to the disciplinary diversity of equipment and procedures used. The design of a training programme for future surrogate inspectors is an important task because the human factor largely determines the effectiveness and success...
Our recent research in an integrated optical interferometer has led to the development of a very low noise optical seismometer based on such transducer. The performances of the transducer combined with the appropriate technical choices for its integration leads to a seismometer which is able to measure subnanometrics earth displacements over a very wide bandwidth. Our optical seimometer has an...
The Flexpart Atmospheric Transport Model (ATM) is traditionally driven by ECMWF and GFS meteorological model inputs. Flexpart-WRF is a variant of the standard model that accepts a wide range of Weather Research and Forecasting model (WRF)-generated meteorological inputs to support very high resolution simulations over customized domains. The chain of activities needed to produce custom...
As part of the GIMO software platform, developed to facilitate the implementation of on-site inspection (OSI) search logic, specific applications have been developed to meet the requirements of the on-site field laboratory. Broadly, these provide a framework and tools to meet the requirements of environmental sample chain of custody, and sample management in the laboratory including sample...
Distributed acoustic sensing (DAS) is experiencing an exponential growth. Although some difficulties in applying this technology to solve some problems of seismology have been encountered, however the main obstacle is insufficient metrological assurance. For each virtual sensor (channel), a lot more work is required in determining its positioning, orientation, transfer function and self-noise,...
Seismic events recorded by the Northwest Mexico Seismic Network are initially located through an automatic system and then manually refined by an analyst. However, this procedure is far from ideal because the considerable dispersion observed in the earthquake cluster does not allow a precise source location. To obtain higher resolution hypocentral locations and thus provide more knowledge and...
Mantle transition zone is delimited by two seismic discontinuities at 410 km and 660 km. These are imaged under the northwestern corner of South America using the receiver function technique and a seismological record with up to 30 years registered by the national seismological network of Colombia. Significant variations and spatially systematic in the discontinuity depths were observed. The...
The trigger for the 2019 National Data Centre Preparedness Exercise (NPE) scenario (a fictitious nuclear explosion) was based on a real ML 3.7 shallow tectonic seismic event within an earthquake swarm in southern Germany, near the city of Constance. The event occurred at 23:17 UTC on the 29 July 2019 (e.g. see International Seismological Centre bulletin) and is not found in the...
Two oceanic plates are converged offshore around the Japanese Islands, in which the Philippine Sea plate is subducting at the Nankai trough in southwest Japan. Historically, a mega-thrust earthquake is repeated every 100-150 years along the Nankai trough, and the last earthquake series occurred in the 1940s. For this reason, real time sea floor observatories for earthquake and tsunami...
Calibration of seismometers used in nuclear explosion monitoring systems, such as the International Monitoring System, is important for providing confidence in the measurements of ground motion and the resulting analysis that is performed on the waveform time series data. Six models of seismometers widely used at International Monitoring System stations have been calibrated using high...
Despite remote waveform analysis and nuclear signatures, an on-site inspection (OSI) remains as the final verification regime for potential indicatives of ambiguous events of CTBT violation(s), which is designed to produce conclusive evidence. As the potential violator, the inspected State Party is accustomed to the procedures and tools available to the OSI, the success of an inspection...
The Jordan Seismological Observatory (JSO) participated in a workshop in Nepal on improved seismic event location using the regional seismic travel time (RSTT) method. The JSO contributed with a list of selected seismic events to be analysed and tested.
After selecting the most matched event from the list and ensuring it was compatible with RSTT module specification, the result of the...
During last year a large volume of tasks was made in our high-precision tiltmeter’s instrumental complex installed in the underground geophysical laboratory of IPE RAS situated at deep adit in Andirci mountain not far from of the Elbrus volcano. The main scope of work was devoted both to improving the instrumental park of the laboratory and to carrying out a set of works on precision spatial...
The use of synthetic aperture radar (SAR) data is a powerful and well established method for remote sensing that enables high resolution measurement of important geophysical parameters such as surface topography, deformation or subsidence of the surface as a result of various processes (earthquakes, tectonic activity, movements of glaciers, mining activity, etc.). The present study illustrates...
In this research, a new optical sensor is used to measure the suspended mass displacement in the seismometer. In the last decades, scientists have used optical interferometer set-up to improve accuracy in displacement measurement. To integrate such optical measurement in a seismometer, all the optical functions, as beam splitter, are integrated in an optical substrate. The only remaining...
The International Committee on Global Navigation Satellite Systems (ICG), as an international multilateral platform under the United Nations Outer Space Agency (UNOOSA ), is promoting voluntary cooperation on matters of mutual interest related to civil satellite based positioning, navigation, timing, and value added services. At the same time, the On-Site Inspection (OSI) Division of CTBTO, as...
VNIIA is a leading company of Rosatom State Atomic Energy Corporation in CTBT implementation, which currently performs a range of researches:
- develops a scientific and methodical support and hardware and software for CTBT on-site inspection (OSI) activities, provides a comprehensive assessment and analysis of efficiency of controls and data information content published by the International...
Reliable and comparable measurements of physical quantities require traceability to the international system of units (SI). Sound pressure is traditionally quantified using measurement microphones as transfer standards, for which the established primary calibration methods are currently limited to frequencies of 2 Hz and higher. These frequencies do not fully cover the range of interest for...
The transversal fault zone Vlora-Elbasan-Dibra (VED) with Northeastern strike dislocated the structure of Albanides along all their width. This transverse fault is the most active zone, which has generated earthquakes along its entire length. This study covers the period from 2004 to 2022.,This time period was chosen because it consists of the increase in the installations of digital broadband...
Recent development in infrasound noise models (Marty et al, 2021) and progress in digitizers’ and microbarometers’ design allows the introduction of precise infrasound noise studies for new installation and for station upgrades. IMS/ED/SA has compiled a library of equipment self noise data and background infrasound noise data of IMS infrasound stations based on percentile calculations. The...
Over the past five years ASIR has adapted silicon audio (SiA) interferometer based sensors in our borehole broadband seismometer, model ASIR ABB, for making seismic observations in ~100 to 1000 m deep slim boreholes. The shifts are used to rapidly and accurately control a force-feedback circuit. The current ~60 mm outer diameter triaxial SiA sonde has been installed in drill hole with inner...
Ambient seismic noise (ASN) is defined as small vibrations recorded throughout the Earth’s surface. The generating noise sources are classified into anthropogenic sources (<1 s) and natural sources (>1 s). In this study, we used data from the Romanian Seismic Network (RSN) stations, operated by the National Institute for Earth Physics (NIEP) and we analysed the influence of atmospheric...
The conduct of an on-site inspection (OSI) in an area other than flat has been considered as an additional challenge to the intrinsically demanding characteristics of such a mission. An effort has been made in the past by the Provisional Technical Secretariat (PTS) to identify those difficulties that are particular to the conduct of an OSI in a mountainous environment and to develop...
The behavior of the inspected State Party (ISP) is one of the elements that has not been adequately analysed in an on-site inspection (OSI), though the same has a grave impact on the inspection. Generally, three distinct common scenarios lead to a request for a review: ambiguous natural events that associate with partial nuclear emission, nuclear accident and a violation of the Treaty via a...
According to Iraqi Radiation Law No. 99 of 1980, the Radiation Protection Center (RPC) is a regulatory body in Iraq responsible for monitoring radiation workers. This is done by providing them with personal dosimetry TLD, ED, monitoring Iraqi environment (soil, water, air) and gamma radiation monitoring. For their health and safety we prepared and designed the wallet card to maintain the...
Relative humidity sensor is one of automatic weather station (AWS) component. Based on annual quality control, relative humidity sensor data have approximately 7% of unavailability because of system maintenance in 2020. This study proposes design of relative humidity virtual sensor according to competitive sensing concept. It is simulated on three AWS in northern Middle Java Province of...
The Joint Task Force for Science Monitoring And Reliable Telecommunications (SMART) Subsea Cables is working to integrate environmental sensors (temperature, pressure, seismic acceleration) into submarine telecommunications cables. This will support climate and ocean observation, sea level monitoring, observations of Earth structure, tsunami and earthquake early warning and disaster risk...
The airborne simulator, used to develop and test on-site inspection (OSI) airborne equipment configurations as well as train surrogate inspectors, is being upgraded to provide more realistic training opportunities. The simulator, a converted Mi-2 airframe, now features adjustable window panels and is being supplemented with a projection system that will provide real world views of the terrain....
In practical scenarios, on-site inspection (OSI) could be conducted in a place of nowhere which is in an environment with radiation hazards. Both OSI training courses and Integrated Field Exercises should take into full consideration such conditions, so as to build up the inspection team's operational capacity for real cases. From the perspective of inspection team functionality and inspection...
Version 3 of Geotool (aka GeotoolQt) provides a powerful, easy to use interface with data import facilities for International Monitoring System(IMS) and non-IMS stations. IMS-related information, including parameters of events and arrivals, as well as waveform data, can be imported directly from VDMS while non-IMS information can be directly retrieved from FDSN web services, including but not...
Seismic hazard assessments (SHA) have not been conducted in large parts of Sub-Saharan Africa (SSA) due to incomplete earthquake catalogues, sparse seismic networks, etc. raising concerns on needed information for planning and disaster risk management. The aim of this study is to bridge the research gap using modern techniques for across the board SHA. Updated catalogue from local networks,...
Contrary to earlier beliefs of being aseismic, Nigeria witnessed numerous earthquakes between 2018 and 2022. The 5-7 September 2018 events with moment magnitudes 2.5-3.7 and intensity II-V, occurred in Mpape, Abuja, about three kilometers from Nigeria's presidential villa and critical facilities such as dams, nuclear research reactors, etc. This study aims to adopt an integrated investigation...
The spectral characteristics of seismic and infrasound noise were calculated by the waveforms of the NNC RK network stations using PQLX software. The calculation results were compared with the seismic noise model by Peterson and infrasound noise by Brown. The daily and seasonal noise variations were analysed. Special attention was paid to regularities of the level change at microseismic...
Tehri dam is an earth and rock filled dam situated in the 700 km long earthquake gap in between the 1905 Kangra earthquake in the west and the 1934 Bihar-Nepal earthquake in the east region of Himalaya and built across the Bhagirathi River. The purpose of the dam is to provide irrigation and generate hydroelectricity for nearby areas. It is operated and maintained by Tehri Hydro Power...
The International Monitoring System (IMS) of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) is designed to detect nuclear explosions with a minimum yield of one kiloton of TNT equivalent worldwide. The IMS uses four verification technologies - seismic, Infrasound, hydroacoustic and radionuclide - in a synergistic manner to enable the detection, location, and identification of...
Short period seismometers were the workhorse of the World-Wide Standardized Seismograph Network built in the 1960s. Because they have very low noise in the band of interest for array seismology, they continue to be used in arrays throughout the International Monitoring System (IMS) of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO). In an earlier study, we used single frequency...
Madagascar has never experienced any volcanism activity. The volcanisms dated from the cretaceous period are almost all around the coastal zones and Cenozoic at the central part and in the north. Seismically, the central part is the most active. An ancient crater even had smoke from the inside slope. The laboratory of Seismology and Infrasound at the IOGA uses the national seismic stations...
Compared to many other Treaties and international conventions, one of the unique and in-built characters of the Comprehensive Nuclear-Test-Ban Treaty is its Protocol. Considering the sensitivity that is required to address the verification regime, having limitations and even restrictions on matters pertaining to national security is understandable. Yet, listing the tools as a part of the...
The International Monitoring System (IMS), the International Data Centre (IDC) and the on-site inspection (OSI) are the technical elements of the CTBT verification regime (CTBT Art. IV); these are designed to detect any nuclear explosion anywhere (underground, under water or in the atmosphere) and to investigate any findings associated with its occurrence. The role of the IDC is to operate the...
Various seismic precursors are known to be preceded small to large earthquakes. These pre-earthquake signatures which may continue to several months and/years would be employed for earthquake forecasting. In the present investigation precursory seismicity patterns were discussed and used for the identification of precursory swarm to forecast the location of future earthquake in the South...
To meet the requirement to certify that on-site inspection (OSI) deployed equipment has been calibrated, maintained and protected, as mandated by paragraphs 38 and 39 of Part II of the Protocol to the CTBT, the Provisional Technical Secretariat (PTS) has introduced a number of supporting tools. This paper highlights initiatives to protect equipment and those used to support and record the...
Seismic moment tensor (MT) inversions have become an important method for characterizing source type (e.g. earthquake, explosion, collapse), seismic moment and depth. However, these methods commonly use average plane-layered one-dimensional (1-D) Green’s functions (GF’s). For areas where path-specific structure is complex, 1-D GF’s cannot fit observed waveforms and source parameters from MT...
Data collected from IRIS Reviewed Bulletin for East Africa is used to generate empirical regression equations using orthogonal least square regression (OLSR). The regression best-fit line yields a regression equation y=0.517x+ 2.1787 with R2 0.6208 for 972 events with a cut-off magnitude of 2.5. While the R2 error is relatively high the result compare published regression equations. The slight...
We present a new 3-D shear velocity model for the crust-uppermost mantle structure beneath the Caribbean region from the surface down to 150 km depth. Our velocity model was derived from joint inversion of group and phase velocity dispersion data obtained from ambient noise and earthquake data. The group and phase dispersion curves estimated from ambient noise were calculated from...
Geophysical data has been gathered to assess these data sets to achieve reliable earthquake re-localisation. These data would serve as input for the Regional Seismic Travel Time (RSTT ) global model's workflow to achieve accurate RSTT in Venezuela and the Venezuelan part of the Caribbean Sea. Therefore, the data sets are extensive including the compilation of earthquakes, mine blasts and...
Unknown to the most Egyptians, of all natural hazards earthquakes pose the greatest damage potential. Large scale events are fortunately quite rare, however, if they strike, they can cause far reaching and very costly damage, which lead to potentially hundreds or even thousands of fatalities. So far, earthquakes cannot be prevented or even reliably predicted. But, due to extensive research,...
The recent strong densification of seismic networks and the increase of data availability from different type of sensors/networks (low-cost, Raspberry-shake, temporary deployments with hundreds of nodes, etc.) questions our ability to automatically and accurately detect, locate and characterize seismic events combining these composite and large data sets. These steps are however key issues to...
This research presents seismic studies review through history up to contemporary days to understand the behavior of earthquake occurrences in Azerbaijan and the interrelation between geodynamics and seismicity. Azerbaijan is situated within the central part of the Mediterranean active belt with seismicity stipulated by intensive geodynamic interrelation of Eurasian and Arabic lithosphere...
Sabah is the most seismically active state in Malaysia where it has recorded higher number of moderate seismological activities for the past decades. The seismicity map of Sabah shows the presence of two zones of distinctive seismicity, which are Ranau in Kota Kinabalu and Lahad Datu in the southeast of Sabah. The International Monitoring System (IMS) network set-up by the Comprehensive...
We report on advances in capabilities toward detailed three-dimensional (3-D) density evaluation of shallow underground features. We are currently developing software to use a 3-D Geological Framework Model (GFM) to predict gravitational anomalies from underground structures such as faults, cavities or tunnels that might be detected with surface and/or subsurface gravity measurements. This...
This research is to study earthquakes strong motion. According to the fact that the factor affecting peak ground acceleration (PGA) is distance, measurement PGA of earthquakes events were collected and have been selected and analysed to find the ground motion prediction equation (GMPEs) in Thailand to estimate seismic hazard or an effected area during a future earthquake in Thailand. The...
Jordan seismic activities are attributed to the Dead Sea Fault. It is an active transform fault extended from the Red Sea to the Taurus/Zagros Mountains. In cooperation with the Comprehensive Nuclear-Test-Ban Treaty Organization we used available local data, IMS data, and arrival times of seismic events with a magnitude greater than 3.5 to be able to validate the location accuracy. The...
The objective of this study is to characterize the recent stress distribution on the Main Marmara Fault (MMF) through quasi-static modeling of inter-seismic strain accumulation by considering past earthquakes and heterogeneous interseismic coupling. Since the MMF is prone to creating large earthquakes, it is crucial to infer the state of stress on the fault. The obtained pre-stress...
The current manuscript comes to answer a controversial question: Is the local earthquake activity in Kuwait a result of tectonic circumstances or anthropogenic? Kuwait is an oil-producing country from which oil is extracted in many places and earthquakes occur simultaneously with the extraction of oil. Seismic activity inside Kuwait is monitored with high accuracy and continuously after the...
The primary seismic station PS14-ROSC is located near the town of Rosal in the central part of the eastern cordillera, close to the Colombian National Seismological Network headquarters. The signal to noise ratio of seismic data shows low quality data. Using the power spectral densities (PSD), we analysed changes in the seismic background noise levels in the station. We integrated microtremor...
Variations in strain/stress and fluid content can change seismic velocities in the subsurface. Monitoring velocity changes, e.g. using ambient seismic noise, may thus constrain these variations as well as the material elastic properties and their non-linear behaviour. In our study we investigate variations of seismic velocity on a short time scale. We use coda wave interferometry to inspect...
Crustal rocks containing cracks and other internal flaws are characterized by nonlinear elasticity, a phenomenon that can be observed in laboratory experiments under applied stress. Stress sensitivity of elastic moduli is associated with opening/closing of cracks under applied stress. In this study we emulated rock laboratory protocols by measuring elastic wave speed using empirical Green’s...
The purpose of this study is to improve the hazard model and the accuracy of the Romanian earthquake catalogue (ROMPLUS) by determining the one-dimensional (1-D) velocity model in a complex collision setting at the bending of Southern Carpathians. To achieve this aim, we investigate 314 low to moderate-sized local, crustal events (Mw 1.0 - 3.4) that occurred from 2019 to 2021. The waveforms...
Seismic hazard assessment for Madagascar based on probabilistic analysis method (PSHA) is carried out after determining the three main parameters such as the mean seismic activity rate (λ), the b-value called Gutenberg-Richter value, and the maximum magnitude mmax. An earthquake catalogue was compiled from data combined between two sets of bulletins by the MACOMO and National Data Centre...
This study aims to estimate earthquake magnitude quickly using vertical component data from Broadband seismographs for the improvement of tsunami warnings. Empirical relationships were obtained for displacement and integrated displacement with moment magnitude. Data selection of seismic records was done before estimating the relationships of amplitudes by observing the number of amount of data...
The conventional picture of the seismicity in Finland, and the rest of Fennoscandia, has been that earthquakes are mostly individual or doublet events without fore or aftershocks. This notion of apparent singularity is based on automatic detection and classification tools and manual analysis workflow designed for regional events visible on multiple stations over a relatively sparse seismic...
The San Miguel volcano is considered one of the most active volcanoes in El Salvador due to its multiple eruptions; however, its structural properties are not fully understood. Four broadband seismometers were deployed by the Ministry of Environment of El Salvador from February 2014 to April 2014. We analysed ambient noise data using the spatial autocorrelation (SPAC) method and seismic...
Ghana is positioned far from any active plate boundaries at the southeastern part of the West African Craton. Elmina, Cape Coast, Saltpond, and Winneba are the four main towns located along the coast of Central region, being one of Ghana's sixteen regions. The seismicity in the regions are stable, with the exception of Greater Accra, Eastern, and part of Volta region that are notable...
Seismic site effect is a dominant parameter of seismic hazards analysis. We present an experimental study of microtremor data to investigate the dynamic characteristics of soil and structures at the Chiang Mai basin, Northern Thailand. The Chiang Mai basin was constructed on terrace sediments and alluvium sediments. The horizontal vertical spectral ratio (HVSR) analyses of ambient noise data...
In 2018 a series of large damaging earthquakes in Lombok-Indonesia occurred close together, causing many casualties and property damage. Therefore, we conducted source models composed of asperities for the 2018 Lombok Earthquake sequence using strong motion data and estimated by the empirical Green’s function method. We simulated the target event with a smaller event in the surrounding area....
Seismic tomograms of the uppermost subcontinental lithosphere (USCL) beneath southern Africa are key to improving knowledge of the correlation between the surface geology and velocity anomalies in the region. The regional distribution of seismic wavespeed anomalies (SWAs) provides a means to delineate known structural features and to find new regions of SWAs within the model space. Delineated...
Java Island is an area with high earthquake activity, one of these activities is caused by the impact of the Indo-Australian Plate, which hits the Eurasian Plate, causing a subduction zone along Java Island. Besides the subduction route, Java Island also has earthquake sources from active faults. This study aims to image tectonic patterns based on the structure of wave velocity models. The...
The Caucasus region lacked a comprehensive catalog, despite its role in Arabia-Eurasia convergence between the Black and Caspian Seas. The Lawrence Livermore National Laboratory and the Institute of Earth Sciences (IES) at Ilia State University generated a new, comprehensive seismic catalog for the period from 1951 to 2019 for the Caucasus region by combining data in the IES bulletin with...
Aswan is a very important city located in the southern part of Egypt, with several cultural heritage sites and critical infrastructure, including the High Dam. The High Dam is located near one of the most seismotectonically active zones, the Kalabsha fault zone. This zone witnessed the strongest instrumental earthquake in Aswan in November 1981, with Mw = 5.8. The current study aims to study...
Seismic array was developed in 1960s mainly to enhance signal noise ratio. Since then many array have been deployed around the world with varying geometry and aperture length based on the purpose of study. Many seismic analyses techniques have been developed, such as beamforming and F-K analysis, in order to achieve the desired results from the data. Hoqain seismic array in Oman is one of the...
We investigated seismic attenuation characteristics of the Lower St. Lawrence seismic zone. This zone is located ~400 km downstream from Quebec City and is between the Quebec North Shore and the Lower St. Lawrence. Coda Q was determined using 847 earthquakes (2.0 ≤ M ≤ 5.1) recorded on ten stations of the Canadian National Seismic Network (CNSN) in Quebec from 1985 to 2022. We find that the...
El Salvador is located in northern Central America, along the Pacific Ocean margin. San Salvador is located in a region with a high rate of seismic activity, as it is part of the El Salvador Fault Zone (ESFZ). Currently, there is no detailed information on the stress and deformation regime in San Salvador. In this sense, the present project is oriented to the analysis of the local...
Romania's participation in the global system of verification of nuclear experiments by seismological means is carried out within the National Institute for Earth Physics by hosting the National Data Centre of Romania (ROM-NDC) and operating and maintaining the auxiliary seismic station Muntele Rosu (AS081, MLR) as part of International Monitoring System (IMS). The main purposes of this study...
Seismic data collected by the Costa Rican OVSICORI-UNA seismic network is used to study the spatiotemporal seismicity and tectonic, related with the Mw 6.7, 21 July 21:15:07, 2021 earthquake, located in the Panama Fracture Zone, 114 km south of the Burica Peninsula. In this zone the relative motion of the Cocos and Nazca plates, accommodates the stress mainly by right-lateral strike-slip...
Macro seismic intensities are a key factor to support the seismic hypocenter location, moreover, this kind of information contributes to sample the Mercalli Modified Intensities (MMI) felt in each city, which can vary along the earthquake ray path. In our country the MMI has been collected since the OSC-NDC foundation, however, over the last 20 years this task was discontinued due to the lack...
Location algorithms have relied on one-dimensional (1-D) velocity models for fast, seismic event locations. The fast computational speed of these models made them the preferred type of velocity model for operational needs. Three-dimensional (3-D) seismic velocity models are becoming readily available and usually provide more accurate event locations over 1-D models. The computational...
After opening for signature of the CTBT (24 September 1996), the PTS began working on the establishment of a global verification regime to monitor its compliance (17 March 1997). The verification regime includes both non-technical and technical elements (defined in Article IV of the treaty); while non-technical refer to diplomatic actions and confidence building measures within States Parties,...
In 1993, a shallow earthquake sequence occurred in Rock Valley, Nevada National Security Site. The largest event, M3.7, was followed by eleven M>2 events ranging in depth from 1-3 km. All events were well constrained due to the deployment of stations early in the sequence. Comparison of these shallow events to nearby historic nuclear tests identified gaps in our ability to discriminate these...
In 2001, the first data from an IMS infrasound station arrived at the IDC. The IDC infrasound processing system was in a premature state and a multi-year development effort was initiated, which led to the completion in 2010 to the first operational infrasound automatic processing and interactive analysis systems. In thirteen years the IDC produced over 45,000 infrasound events reviewed by...
The Source Physics Experiments (SPE) are a series of controlled chemical explosions at the Nevada National Security Site to gather observations, validate physics-based numerical models and understand the genesis of shear waves to improve nuclear discrimination and monitoring capabilities. Executed between 2011 and 2016, Phase I of SPE encompassed six collocated chemical explosions executed in...
Calibration activities for infrasound stations of the International Monitoring System (IMS) are a requirement of the Operational Manual for Infrasound Monitoring and the International Exchange of Infrasound Data. Until 2011, significant technical and scientific challenges prevented full compliance with these requirements. This included the absence of available techniques to characterize...
On 18 May 2020, a seismic event with mb 4.7 and MS 3.9 (International Data Centre) occurred in Kiruna, northern Sweden, at an active iron mine (Luossavaara-Kiirunavaara AB, LKAB). This event was widely observed at broadband seismic stations throughout Nordic countries and as far away as Iceland, Greenland, the UK and continental Europe. Both the operating mining company and various...
Long term infrasound event bulletins are useful for identifying repeating sources from a common location, quantifying source characteristics and studying the time-varying nature of the atmosphere. We produce a regional infrasound bulletin in the Korean peninsula region for the time period from 1999 to 2021. We use data from six infrasound arrays in South Korea, cooperatively operated by...
Atmospheric concentrations of radionuclides measured at International Monitoring System (IMS) stations can vary by an order of magnitude or more between neighboring stations and from one collection to the next due to changes in weather, emission rates of background sources and other local factors. Large spatiotemporal changes make it difficult to categorize elevated collections as anomalies of...
The São Jorge seismovolcanic crisis in 2022 provided an opportunity to deploy a portable infrasound array (SJ1) on the island, in a collaborative work between the University of the Azores (UAc) and the University of Florence (UniFI). This four-element array became operational on 2 April 2022 firstly with a diamond geometry, and after 3 May 2022 with a centred triangular design. Therefore, SJ1...
The Forensic Radionuclide Event Analysis and Reconstruction (FREAR) tool performs source reconstruction using a Bayesian inference framework. Using a statistical model of the radionuclide detection system and atmospheric transport models, FREAR infers and reconstructs the best emission source characteristics to fit the supplied observations. This powerful approach provides assessments...
The CTBT-IMS global sensor network comprises three waveform technologies: Seismic, hydroacoustic, and infrasound, designed to monitor the world continuously for any nuclear explosions on the ground, in the ocean, and the atmosphere. Waveform signals at CTBT-IMS stations can present complex arrival characteristics caused by 3D features along their long-range propagation paths. This panel will...
Sensor data from radionuclide systems within the International Monitoring System (IMS) provides critical information about the operating status of a given station. Many of the algorithms currently in place monitor large immediate sensor deviations and provide alerts. Small sensor changes, especially over extended periods of time, are more challenging to detect. Another challenge is quickly...
The International Monitoring System operates a network of radionuclide technology monitoring stations. Historically, each measurement has been analysed separately to verify treaty compliance. Combining sample measurements, including detects and non-detects, invokes greater monitoring capability referred to as network power. A key steppingstone to obtaining network power is to objectively...
Inverse modelling allows to determine source parameters of an atmospheric release of radioactivity by combining atmospheric transport modelling and airborne radionuclide measurements in a statistically coherent manner. A series of inverse modelling experiments will be conducted using real-world Xe-133 observations from the International Monitoring System and the Forensic Radionuclide Event...
Modernization of technology and work processes during the last decade at NORSAR. How technology, state of health (SOH) monitoring and efficient work processes can contribute to quality, data availability and increased performance. In the last few years NORSAR has established a modernized SOH system based on Nagios, PostgreSQL and Grafana to monitor and log uptime and SOH of our installations...
In the context of CTBT verification, radioxenon ratios can be used to discriminate between nuclear weapons domain signatures and nuclear facilities as plausible sources of the observed atmospheric radioactivity. This discrimination is accomplished by setting a screening flag threshold beyond which a radioxenon sample can be considered as being possibly of relevance from a nuclear explosion...
The auxiliary seismic network of the International Monitoring System (IMS) is comprised of 120 seismic stations. It is designed to support the primary seismic network to increase detection accuracy, for earthquake monitoring and nuclear test detection. Some auxiliary stations have been designated as temporary substitute primary stations. Auxiliary seismic stations are deployed at remote areas...
The United States supports the Comprehensive Nuclear-Test-Ban Treaty (CTBT) and is committed to work to achieve its entry into force, recognizing the significant challenges that lie ahead in reaching this goal. Consistent with the goals of the CTBT, the United States continues to observe a moratorium on nuclear explosive testing and calls on all states possessing nuclear weapons to declare or...
In recent decades, the tripartite micro arrays (i.e. three-element array) became a major tool for the passive seismic phase of the on-site inspection, mainly due to their superior back azimuth estimation. However, the back azimuth is estimated under the assumption of far field approximation while tripartite arrays are used to monitor micro-seismicity and aftershocks in the vacancy of the...
We have been considering spatio-temporal variations of S wave attenuation field structure in the region of the Semipalatinsk test site (STS). We studied variations of amplitude ratio for Lg and Pg waves (parameter Lg/Pg) using seismograms of underground nuclear explosions (UNEs) and also calibration and quarry explosions, obtained by stations TLG and MKAR. We revealed essential temporal...
The Comprehensive Nuclear-Test-Ban Treaty language on an Inspected State Party’s right to portions of samples taken during an on-site inspection (OSI) is very similar to sampling language in the Chemical Weapons Convention (CWC), reflecting an overlap amongst negotiators involved. There are small differences in the treaties’ wordings, however, and in the case of the CTBT these differences have...
Historical geophysical data recorded during the peak of nuclear testing is rare and limited. Efforts have been made to preserve and digitize data but have minimal quality control from decades of lost history and retiring personnel. Furthermore, recent research into the subsequent collapses of cavities is stifled by the lack of continuous records to investigate historical collapses.
The...
Radio timing services failed for the first nuclear test (TRINITY, 16 July 1945), but were available to determine the origin time of an earlier 108 ton TNT explosion, conducted nearby on 7 May, 1945. We have scanned and digitized the vertical-component analog seismograms recorded at Tucson Observatory (TUO, at a distance of 437 km) for both events. These regional signals include Pn and Pg, and...
Since 1875, the Metre Convention has established the principles for all nations to act in common accord in matters relating to units of measurement. In 1960 the system became known as the International System of Units (abbreviated SI from the French "Système International d'Unités"). Today, the SI is the widely accepted basis for the international mutual recognition of measurement results and...
In the current age of technological innovation detecting illicit underground testing of nuclear weapons is a challenging task. However, remote sensing technology like unmanned aerial vehicles (UAV) is trying to provide solutions to some unresolved problems in our society and environment. UAV is a new and emerging technology that has a direct impact on the economy and society. It has a wide...
The Redmond Salt Mine Monitoring Experiment in Utah was designed to record seismoacoustic data at distances less than 50 km for algorithm testing and development. During the experiment from October 2017 to July 2019, six broadband seismic stations were operating at a time, with three of them having fixed locations for the duration, while the three other stations were moved to different...
Any system that intends to provide reliable and trustworthy information demands quality processes that are commensurate with the complexity of the system and criticality of the data. The IMS is highly demanding in both respects. Therefore, the quality system infrastructure being developed and implemented for the IMS seismo-acoustic operations aims at realising these goals through unprejudiced...
An attempt is made to assess the quality of the Review Event Bulletin (REB) by comparing it to the Bulletin of the International Seismological Centre (ISC Bulletin). To compare, the ISC Bulletin events as downloaded from the ISC Web page for the month of October 2020 was used. The corresponding IDC REB events as listed in the ISC Bulletin were considered. During this period, a total of 3431...
Underground nuclear explosions induce a strong flow of air through the surrounding fractured porous media, which carries radionuclides or chemical species. While radioxenon and 37Ar represent tracers scrutinized by the International Monitoring System and On-Site Inspection, respectively, a larger variety of tracers is emitted at the ground surface: radioxenon and heat generated by the...
Seismometer arrays form the core of the International Monitoring System (IMS) waveform network, and enhancing signal detector performance should lead to improvements in the performance of all subsequent parts of the International Data Centre (IDC) waveform processing pipeline. Recently a test data set was released by the IDC composed of signal detections made by an implementation of the...
Molten Salt Reactors (MSRs) are a Generation IV nuclear reactor design that is currently under development and testing in various countries around the world. The molten fuel provides an opportunity for continuous processing of gaseous fission products which may impact the International Monitoring System (IMS). Simulations were performed for four MSR designs to predict the production of...
The International Data Centre (IDC) of the Comprehensive Nuclear-Test-Ban Treaty Organization continues to develop the advanced automatic and interactive software NET-VISA, which uses state of the art machine learning and artificial intelligence techniques to do next generation automatic seismic event detector, based on Bayesian inference. The automatic seismic event bulletins it creates,...
We will review data from Phase II testing of Xenon International at RN33. Xenon International is a new generation radioxenon monitoring system developed by PNNL with a short sampling time of 6 hours. Phase II testing of Xenon International was conducted from July 2021 to April 2022 at International Monitoring System (IMS) radionuclide monitoring station RN33 on Mount Schauinsland, Germany....
Seismic waves are sound waves emitted by, for example, an earthquake or an underground explosion. Accurate estimation of the back-azimuth, i.e. the direction of arrival (DOA), of a seismic signal to the detecting station, is required for the accurate localization of seismic events. This is especially important in the case of seismic arrays, which comprise a substantial portion of International...
The National Data Center Preparedness Exercise 2019 (NPE- 2019) provides an opportunity to evaluate the ability of the National Data Center (NDC) to use available International Monitoring System (IMS) data, techniques, and tools to verify compliance with the Comprehensive Nuclear-Test-Ban Treaty. In NPE-2019, there are unusual detections of radioactive particulates (Cs-134, Cs-137, La-140, and...
The need for common understanding and adoption of good practices and measurable ways to ensure safety and security in the development and deployment of different technologies are some of the "Raisons d'être" of standardization and certification. This presentation aims to create awareness about standardization, some areas of relevance for the CTBT, while encouraging dialogue with regards to...
This presentation will highlight background measurements of Ar-37 samples that were conducted at in Knoxville, Tennessee, USA to better understand the sources of atmospheric concentrations of Ar-37 using the Argon-37 Field System. The PNNL designed and built Argon-37 Field System has now processed and measured several hundred Ar-37 samples from both the soil gas and from the atmosphere. The...
Accurate timing is both an essential requirement and a perennial problem for seismology. With the adoption of satellite based global positioning systems for the timestamping of data in the 1990s, this problem appeared to have been solved. I have applied multichannel cross-correlation (VanDecar & Crosson, 1990) to recordings of teleseisms across seismic arrays, to estimate the relative timing...
The purpose of the panel on “Introduction of the synergies between professional societies and the CTBTO” is to introduce the audience to the professional societies that are represented on the podium and to inform about their CTBT-related activities.
There is no discussion expected but Q&A will be permitted.
CTBTO is hiring professionals in STEM fields – Learn about CTBTO’s Recruitment Process
Come and find out more about how to join the CTBTO! Visit us at the HR booth and speak with the CTBTO Human Resources team and learn more about CTBTO careers. You can also join us in our HR presentation where we will walk you through our recruitment process. CTBTO is hiring top talent across a wide variety...
Detection of radionuclides released from a nuclear explosion is an essential task performed by the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) as mandated under the Comprehensive Nuclear-Test-Ban Treaty. Identifying possible source regions for relevant radionuclide observations and identifying potential stations for measuring releases from known source locations is done by...
Starting with 2009, three infrasound stations have been deployed on the Romanian territory by the National Institute for Earth Physics: (1) IPLOR (in central Romania), (2) BURARI (in northern Romania) – under cooperation with AFTAC (USA), and (3) I67RO temporary PTS portable array (in western Romania) as a two-year experiment (2016-2018), within a collaboration project with the Provisional...
Four technologies are used for compliance verification of the comprehensive Nuclear-Test Ban Treaty (CTBT), hydroacoustic, infrasound, seismic and radionuclide monitoring. Forty radionuclide stations will have the radioxenon monitoring capability. For the last few years, a lot of research have been done in order to discriminate radioxenon derived from an explosion and anthropogenic sources....
International Monitoring System H phase stations have great potential for submarine earthquake monitoring in the southern hemisphere. The hydrophones could record low frequency sounds from extensive areas. However, some seismic signals from different areas would have similar characteristics in a short time interval. It is difficult to locate the epicenter using only the azimuth and arrival...
We apply a current state-of-the-art machine learning based denoising algorithm on the seismological and hydroacoustic waveform records of the selected Democratic People's Republic of Korea nuclear tests. We use the DeepDenoiser algorithm to reduce the noise present in the waveform records of the larger Democratic People's Republic of Korea nuclear tests. The denoising of waveform records using...
The US National Data Centre (NDC) observed five relatively large seismic events in the Chhattisgarh Province of India from September 2018 through October 2022. These events are of interest as they exhibit some explosive characteristics, and their respective yields are approximately equivalent to a 1 kiloton underground nuclear explosion. The events occurred near a known coal mine that uses...
On 26 September, 2022 the International Monitoring System (IMS) detected two seismic events near the Danish island of Bornholm. The events were seen in both seismic and infrasound data and were located near the positions where large gas leaks from the North Stream were later observed. The events were furthermore recorded by seismographs in the surrounding countries and analysed at the National...
The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) maintains nine International Monitoring System (IMS) radionuclide stations across Australia, Antarctica, Fiji and Kiribati. A significant proportion of these are considered to be remote locations, where access is limited and local support is essential for the ongoing maintenance of the stations. This was particularly...
Landslides along the Inter-American Highway in Central Costa Rica, between San Ramon and Esparza are common, mostly during rainy season and are more related to instability due to the state of alteration of the materials on the slopes than to local faults. The saturation of the soil and the slopes could lead to the acceleration of these landslide processes even with earthquakes of moderate...
Previous works have demonstrated potential in using infrasound data to constrain earthquake source properties (Hernandez 2016; Shani-Kadmiel 2018, 2021; Averbuch 2020). Typically, the applied approaches are based on comparing modelled and recorded signals. In the current study we seek to constrain the source depth and moment-tensor. We use infrasound data from local and seismic data from local...
The IDA/GSN seismic network consists of 40 broadband seismic stations around the globe. Fifteen stations serve as auxiliary seismic stations of the International Monitoring System (IMS). During the COVID-19 pandemic, travel was severely disrupted. However, after considerable adjustment, network data return remained good and operational costs decreased. This was due to several factors: 1)...
The International Data Center (IDC) at the Comprehensive Nuclear-Test-Ban Treaty Organization routinely analyses data from radionuclide measurement stations of the International Monitoring System (IMS) in support of its mandate. The Standard Screened Radionuclide Bulletin (SSREB) is a product of the IDC that is generated for each radionuclide sample having measured concentrations of...
Two seismoacoustic events occurred on 26 September 2022 close to Bornholm Island in the Baltic Sea. Both events were listed in the Reviewed Event Bulletin of CTBTO as they were detected with the International Monitoring System. As the events were classified as a critical event by the Austrian National Data Centre, the available data were analysed in detail. The earlier event, with a published...
Xenon and iodine isotopes are, among other CTBT-relevant radionuclides, major indicators for nuclear explosions. They are therefore globally monitored by the International Monitoring System to verify compliance with the CTBT, using different technologies. Xenon isotopes are intermediate decay products of radioiodine. If originating from the same source, the radioxenon to radioiodine ratio of...
In the context of the Comprehensive Nuclear Test Ban Treaty (CTBT), the CEA/DAM developed the Système de Prélèvement Automatique en Ligne avec l'Analyse du Xénon (SPALAX) about 20 years ago which is used in the International Monitoring System to detect xenon releases following a nuclear explosion. The New Generation of the system has been successfully developed by the CEA and CEGELEC Défense....
We investigate historical nuclear tests from the Lop Nor region, China, using waveform-based source inversions and three-dimensional waveform modeling. Despite sparse data distributions and low signal-to-noise ratios, we recover isotropic moment tensor solutions for historical explosions and obtain detailed uncertainty information from likelihood evaluations over magnitude, depth, and the...
Sandia National Laboratories is developing the Geophysical Monitoring System (GMS) for modernization of the United States National Data Center waveform processing system. The United States is providing the common architecture and processing components of GMS as a contribution in kind to accelerate progress on International Data Centre (IDC) re-engineering. Open source releases of GMS,...
Radionuclide stations in the International Monitoring System (IMS) network routinely collect air samples and assess activity concentrations. Activities collected in samples are often caused by emissions from nuclear facilities, but they could also indicate a noble gas release from an underground nuclear explosion. A discrimination can be done by estimating and analysing activity ratios of...
Since 2008, the CTBTO has been conducting temporary radioxenon measurement campaigns using transportable systems. These campaigns are focused on improving the performance of the verification system as described in the Treaty. In 2017, the Government of Japan made a voluntary contribution to boost CTBTO capabilities to detect nuclear explosions. In early 2018, two transportable noble gas...
Seismological bulletins from local and regional seismic stations have identified signals associated with mining explosions in the Orapa mining area, Botswana. Here we present the results of integrating detections from regional seismic networks and the International Monitoring System (IMS) network. Using the local bulletins and catalogs, we requested IMS data via the Extended NDC-in-A- Box...
Data from the International Monitoring System (IMS) stations of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) are being processed by automatic processing, Global Association, interactively analysed and reviewed, resulting in International Data Centre (IDC) bulletins. The Network Processing Vertically Integrated Seismic Analysis (NET-VISA) is a Bayesian seismic monitoring...
The National Data Centre of Côte d’Ivoire and the PTS installed a portable infrasound network (I68CI) from mid-January to December 2018 in the Comoé National Park located in north-east Côte d’Ivoire. This mobile station includes four sensors and use MB3d microbarometers with 50 Hz sampling frequency. The main objective of this one-year deployment is to better understand and characterize...
Immediate identification of system component failures through state of health (SOH) trend analysis allows for fast resolution of International Monitoring System (IMS) station issues. The Radionuclide Operations Support System (ROSS) allows staff of the Provisional Technical Secretariat to display station SOH data, assess current station performance, and notify International Data Centre...
The impact of wave propagation effects on the performance of the P/S ratio local discriminant is being evaluated during the third phase of the Source Physics Experiment, the Rock Valley Direct Comparison (RV/DC), conducted at the Nevada National Security Site. During the experiment a chemical explosion will be detonated near the hypocenter of a shallow earthquake. The direct waveform...
On 7 September 2017, the Democratic People’s Republic Korea carried out its latest and largest nuclear test (DPRK6). Recent efforts have been made to increase understanding of this and previous nuclear tests using seismic waveform, and synthetic aperture radar (SAR) geodetic deformation data (e.g. Wei 2017, Chiang et al. 2018, Myers et al. 2018, Wang et al. 2018). In our previous work...
On the Semipalatinsk Test Site territory there are several mineral deposits at some of which the active mining is observed. The most blasts are conducted at Karazhyra coal quarry. Three IMS stations, Makanchi (PS23), Borovoye (AS057), Kurchatov-Cross (AS058), are recording these quarry blasts. The quarry-to-stations distance is 452 km, 668 km, and 68 km respectively. For 19 years of...
In recent years there were several tragic accidents at military depots in the south of Kazakhstan (Arys, Taraz) and in Uzbekistan (Malik) resulting in destruction of buildings, injuries and loss. All these bursts were recorded by Kazakhstan seismic stations. The closest station to the epicenters of all bursts was Karatau seismic array, part of the National Nuclear Center monitoring system of...
When monitoring for potential underground nuclear tests, distinguishing shallow earthquakes from explosive sources can often be achieved using the ratio of the body-wave magnitude to the surface-wave magnitude (mb:Ms), as explosive sources often produce less energetic surface wave excitations than earthquakes with the same mb. Current methods for surface-wave detection at the International...
We introduce infrasound data products of all certified International Monitoring System infrasound stations for scientific studies and applications. We have reprocessed the IMS infrasound waveform data of the last 20 years using the Progressive Multi-Channel Correlation (PMCC) method, configured with one-third-octave frequency bands between 0.01 and 4 Hz. From the comprehensive detection lists...
The International Data Center is required to conduct expert technical analysis (ETA) and special studies to improve event parameters and assist States Parties in identifying the source of specific events, according to the Protocol to the Comprehensive Nuclear-Test-Ban Treaty. Source mechanism and event depth are two parameters which may be crucial for the event discrimination task. To...
Starting in 2010, when the OVSICORI-UNA seismic network was upgraded with 24-bit digitizers and broadband instruments, we selected possible candidates to GT5.0 seismic events from the seismic catalog.
The GENLOC program was used to locate the events and the selection criteria were as follows: 1) minimum number of stations greater than or equal to 30, 2) Gap less than 110 degrees, and 3)...
One of the tasks of the Provisional Technical Secretariat (PTS), in regards to the mandate of the International Monitoring System (IMS) Division, is to support, monitor and conduct maintenance activities. In this presentation an overview of the field missions that the CTBTO maintenance radionuclide team have performed after the pandemic restrictions were lifted will be given. These activities...
The Comprehensive Nuclear Test Ban Treaty (CTBT) prohibits nuclear explosions by anyone, anywhere: on the Earth's surface, in the atmosphere, underwater and underground by using four key technologies such as radionuclide monitoring. Niger deposited its instrument of ratification of the Comprehensive Nuclear Test Ban Treaty (CTBT) with the Secretary-General of the United Nations on 9 September...
Isotopic ratios of radioxenons can be used to verify the occurrence of an underground nuclear explosion (UNE). Simplified analytical models and closed-form solutions using Bateman equations simulate a idealized radioactive decay/ingrowth chain in a closed and well mixed system. The partitioning of the radionuclide inventory between a gas phase and rock melt created by the detonation and the...
For the purpose of monitoring for compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT), the International Monitoring System (IMS) includes 80 sites with particulate radionuclide samplers, 40 of which also have a noble gas sensor system. The coincidence of radioiodine and radioxenon observations at the co-located systems may offer an opportunity for event screening. This study gains...
The Comprehensive Nuclear Test-Ban Treaty Organization (CTBTO) uses infrasound to measure acoustic impulses in the atmosphere that could be indicative of an atmospheric nuclear test or explosion. However, many other events analysed by analysts at the International Data Centre (IDC) and appear in IDC products such as the Reviewed Event Bulletin. Examples include gas pipeline explosions, rocket...
The National Data Center of Kyrgyzstan daily monitors seismic events of various nature, most of which are tectonic earthquakes and quarry blasts. Sometimes seismic stations in Kyrgyzstan register unusual phenomena associated with exogenous geological processes, such as landslides, snow avalanches, rockfalls and mudflows. Landslides and snow avalanches can be caused by both tectonic processes...
We determined root mean square (RMS) amplitudes of Lg waves from the six known underground nuclear tests conducted by the Democratic People’s Republic of Korea. We analysed waveform data from a dozen seismographic stations situated in the Republic of Korea, the People's Republic of China and the Russian Federation operated by the International Monitoring System, Global Seismic Network, and the...
The main purpose of this study consists in applying discrimination methods to distinguish known nuclear tests conducted by the Democratic People’s Republic of Korea from surrounding natural seismicity, based on various seismic signal processing algorithms. To characterize the Democratic People’s Republic of Korea's seismic activity between 2006 and 2022, spectral analysis, waveforms...
Over the past ten years of observations by the seismic monitoring network of the National Nuclear Center of the Republic of Kazakhstan, seismic events of a different nature have been registered on the territory of central Kazakhstan. The largest number of these events are quarry explosions at deposits of solid minerals. But there are also tectonic earthquakes and natural-technogenic events...
The Observatorio San Calixto (OSC) is the National Data Center for the Plurinational Bolivian State. It manages the certified seismic stations PS06-LPAZ, AS08-SIV and one infrasound array IS08-BO. The distances from our center to the far away seismic station is about 1000Km (AS08-SIV) and the other two are located at Altiplano where the environment to work is often hard. In order to obtain the...
This study provides an overview of a civil application of International Monitoring System (IMS) data to assist in disaster mitigation. Two infrasound arrays coupled with seismic stations of the IMS recorded the with Baltic Sea gas explosion on 26 September 2022. Underwater eruptions generate air waves and pressure waves that can cause fluctuations in the different layers of the atmosphere....
This work has the goal to present a useful method to help in the discrimination of natural events (tectonics) from artificial events (chemical explosions in quarries blasting) when both sources are co-located. This is a frequent problem where the seismicity is triggered by stress released due to material removal in mines. With that purpose, we are conducting experiments using local infrasound...
In this study we aim at discriminating hydroacoustic sources by identifying on the one hand source typical signal features derived from event catalogues and by characterizing on the other hand waveform similarities using clustering analyses of raw hydroacoustic data. We make use of event bulletins derived from the application of the Progressive Multi Channel Correlation method on International...
We introduce the Central and Eastern European Infrasound Network (CEEIN) established in 2018 as a collaboration between the Zentralanstalt für Meteorologie and Geodynamik, Vienna, Austria; the Institute of Atmospheric Physics of the Czech Academy of Sciences, Prague, Czech Republic; the Research Centre for Astronomy and Earth Sciences of the Eötvös Loránd Research Network, Budapest, Hungary;...
The International Monitoring System (IMS) of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) comprises four verification technologies that work in synergy to enable the detection, location, and identification of potential nuclear explosions. One of the four technologies is the infrasound which listen to corresponding sound waves. As of 2022, Fifty-three from sixty planned IMS...
Paraguay, located in the middle of South America, is a low seismicity country. Nevertheless it has been collecting data for a long time. The continuous operation of the station gives us the opportunity to select several years of bulletin. This time five years of International Data Centre (IDC) detection (from 2018 to 2022) were selected from bulletins (reviewed and automatics) that are used to...
The Rock Valley Direct Comparison (RV/DC) project is the third phase of the Source Physics Experiment (SPE). Under RV/DC, two chemical explosions will be detonated near the hypocenters of a sequence of anomalously shallow earthquakes on the Nevada National Security Site. The explosions (nominally 1,000 and 10,000 kg TNT-equivalent) will be recorded by an extensive array of multi-physics...
The framework developed and presented here provides a new and transportable method to determine the yields of seismically recorded underground nuclear explosions. The key advantage of this method over other methods which estimate absolute explosive yields is that this method does not require any a priori calibration and can be immediately applied to any region of interest. This method uses the...
Impulsive, low frequency, electromagnetic signals were observed during historic United States underground nuclear tests. The source of these signals is uncertain though a prime candidate is the so-called “magnetic bubble”. This mechanism creates a magnetic signature when the hot plasma shell from the explosion expands in the Earth’s magnetic field. At low frequencies, this signal can diffuse...
Hundreds of years has elapsed since earthquakes started to be instrumentally recorded. However, our understanding of magmatic rifting and other complicated source features that we observe today was limited due to the absence of digital seismic records at epicentral distances of interest. After the advent of digital broadband instrumentation with wide dynamic range, volcano seismology has...
The role of metrology in improving confidence in IMS measurements
Description: The purpose of this workshop event is to disseminate outcomes from the Infra-AUV project relating to the value of robust calibration practices in sensor networks and the associated practical aspects for maintaining sensor systems. The project will be producing a recommended good practice guide for establishing...
Automatic bulletins are created using data from the International Monitoring System (IMS) seismic, hydroacoustic and infrasound stations. These bulletins are interactively analysed and reviewed by the Monitoring and Data Analysis (MDA) Section at the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO). The automatically processed Standard Event Lists (SEL3) are reviewed in detail to...
Accurate seismic station orientation is important for seismic waveform or particle motion based studies. Station misorientation has been studied using P wave particle motion and Rayleigh wave arrival angle, which may be affected by the complexity of earthquake sources. Recently, P wave receiver function (PRF) using tangential component has been proposed for misorientation estimation. In this...
In the framework of application of Comprehensive Nuclear Test Ban Treaty, 371 facilities run across the world to form the International Monitoring System. Madagascar hosts two of these stations, I33MG an infrasound station and AS61, an auxiliary seismic station. These two stations need to operate continuously to detect any nuclear test. To minimize downtime during an eventual outage, the...
Traditional sensing techniques are recognized to be labor and technically intensive for practical adoption. As a result, researchers are employing alternate sensing techniques. One of the major technologies for sensing environment is variations in WiFi channel state information (CSI) that describes the channel state between the transmitter and the receiver. With its sensitivity to...
The Institute of Geophysical Research of the Republic of Kazakhstan conducts work on scanning and digitalizing of archived photo paper seismograms from the CSE IPE AS USSR. The records are digitized using WaveTrack software developed by the Novosibirsk Regional Center for Information Technologies of Russia and adjusted for data saving in contemporary formats. The main task of the project is to...
In close and constant collaboration with the CTBTO, Enviroearth has developed a backup intra-site communication solution working through a cellular network. This backup system was fully designed according to CTBTO specification. Its low power consumption, communication protocol and easy implementation on-site make it well adapted to the infrastructure of infrasound stations and its integration...
The International Data Centre (IDC) receives from stations more than ten gigabytes of raw data on a daily basis. Most of those data are collected and transmitted as continuous data digitally signed frames. In normal operations the frames are received in chronological order of their acquisition/detection time. However, some frames may be missed, corrupted, partially delivered or sent several...
As a solemn legal proof of either Treaty compliance or violation, data security of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) verification infrastructure plays a vital role for the authority of CTBT regime. For most important cases within the CTBT verification infrastructure, such as the International Monitoring System (IMS), data gathered at internationally distributed IMS stations and...
"TianQi" LEO micro-satellite Internet of Things (IoT) constellation, is a commercially running space based IoT system, which is composed of 38 LEO micro-satellites, and will be fully deployed by the end of 2023. Ground terminals are portable and cost effective, with power consumption as low as 100mw. The constellation could provide global users such as CTBTO with "air, ground and sea...
The CTBTO link to the database of the International Seismological Centre (ISC) is a service provided on behalf of and by arrangement with the International Data Centre. The link provides the Provisional Technical Secretariat (PTS) and National Data Centres (NDC) with dedicated access to long term definitive global datasets maintained by the ISC. Functionality includes specially designed...
Sandia National Laboratories is developing the Geophysical Monitoring System (GMS) to modernize the United States National Data Center (USNDC) waveform processing system. The United States is providing the common architecture and processing components of GMS as a contribution in kind to accelerate progress on International Data Centre (IDC) re-engineering. A key aspect of GMS architecture is...
Smartphone accelerometers can be used to record earthquake signals to support disaster mitigation in Indonesia. Human activities produce significant noise to accelerometer data on smartphones. Human activity recognizer (HAR) functions to sort out human activity signals from earthquake signals recorded by smartphone accelerometers. This study aims to reduce the linear acceleration signal of...
The International Monitoring System (IMS) is one of the four elements of the Provisional Technical Secretariat (PTS) verification regime. The seismoacoustic component of the IMS network is comprised of seismic, infrasound and hydroacoustic stations participating in the underground, air, and underwater explosion monitoring. The minimum requirement in terms of data availability for each station...
All CTBTO stations in Indonesia are powered by solar panel although some are helped by commercial power lines. All those systems require a battery bank. Since 2008 until 2021 there was 10 cases caused by battery problem which held up data transmission from six CTBTO stations in Indonesia to the National Data Centre and the International Data Centre. In this presentation we will discuss how to...
The International Monitoring System (IMS) is a globally distributed network of monitoring facilities using sensors from seismic, hydroacoustic, infrasound, and radionuclide technologies. The need for data availability increased the significance of data quality monitoring. This task is addressed through the creation of a platform for the fast and easy identification of data acquisition...
An analysis of the quality of accelerograph data has been carried out from 669 station locations. This aims to monitor and evaluate the data quality of accelerograph equipment at the Meteorology, Climatology, and Geophysics Agency (BMKG). Advances in machine learning can mean the ability to diagnose or even predict equipment problems so that site visits can be scheduled more cost-efficiently....
The detection level of a seismic network is the ability to estimate the level of detection and have a tremendous importance both in the design of a new network and in determining whether a given network can recognize seismicity consistently, or needs to be improved in some way. We determine the detection level of the Cuban seismic network using the empirically estimated seismic noise spectral...
Simulating and analysing the detection capabilities of the seismic, hydroacoustic and infrasound networks of the International Monitoring System (IMS) can contribute to the enhancement of the Treaty’s verification regime and its capabilities. Simulations carried out with the Java-based tool Network Monitoring for Optimal Detection (NetMOD) allow one to evaluate the overall network performance...
The National Data Center of Kyrgyzstan and Michigan State University (MSU) are digitizing historical analog seismograms of nuclear explosions that were conducted at the People’s Republic of China (PRC) Lop Nor test site. The methodology for digitizing and data quality control was developed by the MSU team. Of significant importance is the recovery of original station calibrations and...
The observation of atmospheric radionuclides that are associated with nuclear test explosions has a long history that started already in the 1940s. Over the decades of nuclear testing the methods were refined and mounted into the high-quality systems implemented in the International Monitoring System of the CTBTO. The project presented here is reviewing the publications about off-site...
In a constant evolving digital world, there is a need for flexible way to secure the CTBTO data and products sent over the Internet. High levels of flexibility can be achieved by implementing programable, intelligent, VPN systems that can be deployed without the need for dedicated physical hardware. This system of secure communications can be deployed in as a software implementation,...
The Seismic Network Expansion in the Caucasus and Central Asia (SNECCA) project began in 2019 to upgrade national seismic network capabilities in Armenia, Azerbaijan, Georgia, Kazakhstan, Kyrgyzstan, and Tajikistan. The United States participated in this collaboration with support from the U.S. Department of Energy and Lawrence Livermore National Laboratory. All six countries utilized a common...
The Geophysical Institute in Ecuador uses SeisComP for acquisition of waveforms of around 150 seismometer and accelerometer stations. SeisComP has several modules (SCQC, SCQCV, etc.) that allow the operator to check the quality of the waveforms acquired, nevertheless the module's interfaces could be difficult to use and not very interactive. For easy access to the information of waveform...
The correct operation of a seismic station depends on many factors. A crucial one is the provision of power required for station to operate at the established standards. Given that the Paso Flores, PLCA/PS01, seismic station power system currently in use is at the end of its life cycle, that it was not designed for the current demands and, evaluating all the technologically available...
Many of the primary and auxiliary seismic stations of the International Monitoring System (IMS) have been in operation for more than 20 years. Tracking changes in station performance for this duration can prove challenging, requiring continuously reported data across the time period. Using phase picks reported to the International Seismological Centre (ISC) it is possible to evaluate...
Brazil participates in the CTBTO in several ways, as it has an institution, the National Center for Monitoring and Alerts of Natural Disasters (CEMADEN), which became responsible for the implementation of the Brazilian National Data Center (NDC). The country also has a radionuclide laboratory, RL4, which is in the certification process. In addition to operating an infrasound station, IS9, and...
The spread of radiocesium traces is strongly influenced by the circulation of wind and ocean currents around Indonesia. Seawater from the Pacific Ocean that enters into the Indonesian marine water area could distribute Cs-137 from the Fukushima release. Monitoring results show that the concentration of Cs-137 on the west coast (West Sumatera, Bangka Island, North and South Java, and Madura)...
Capacity building efforts for National Data Centers (NDCs) commonly involve the provisioning and shipment of physical hardware systems and the training, installation, maintenance, and distribution of the NDC-in-a-Box (NIAB) software suite. “NDC-in-the-Cloud” (NIAC) is a set of cloud-hosted resources for National Data Centers that uses cloud services to streamline these efforts, while also...
The security system designed for the Internet of Things (IOT) should be able to detect and prevent both internal and external attacks. This work proposes a lightweight and low energy encryption algorithm to secure data over wireless networks. The proposed algorithm meets the requirements of data and is suitable for wireless devices and sensors. It is capable of reducing the execution time and...
Broadband access and low latency are available globally thanks to the increasing availability of low earth orbit satellites. There are a variety of geographical locations where the International Monitoring System stations are installed that could benefit from this type of service. Maximizing data availability and simplifying complex infrastructure -normally associated with the deployment of...
NORSAR is the Norwegian National Data Centre (NDC) and operates six stations of the International Monitoring System. These are the primary seismic arrays NOA/PS27, ARCES/PS28, the auxiliary seismic array SPITS/AS72, the auxiliary single seismic station JMIC/AS73, the infrasound array IS37 and the radionuclide station RN49. It is crucial to have a stable power supply with a sufficient battery...
During the years of nuclear tests, a network of seismic stations of the Institute of Seismology NAS KR operated on the territory of Kyrgyzstan, the data of which are very important for seismic monitoring purposes. Most of these stations were installed far from natural and anthropogenic sources of seismic noise, on bedrock, in specially equipped bunkers and tunnels. In addition, most of the...
The Flexpart Atmospheric Transport Model is used in daily operations at CTBTO for the backtracking of radionuclides based on measurements at 80 sites worldwide. Over 280 simulations are performed each day and it is desirable to make each simulation run in a shorter period of time. With increased availability of GPU environments, it is natural to consider their potential in speeding up the...
For most of the inspection area, there would be no electricity supply. The inspection team should be self-sufficient especially for the perspective of electricity supply, since that most of the mission critical or health and safety equipment would rely almost solely on electric power. This work proposes a portable flexible solar charging pack for on-site inspection activities. Flexible solar...
During the first half of the 20th century, most earthquake ground motions in Mexico were recorded by the Mexican seismological network, equipped with different Wiechert mechanical seismographs on smoked paper. Nowadays, the analogue seismographic collection of Mexico is stored and maintained at the Joint Library of Earth Sciences of UNAM, as part of the Sismoteca-SSN project, to preserve,...
One challenge of on-site inspection (OSI) is preparing for deployment to unknown locations with unknown resources. A critical element of a functional base of operations (BOO) is stable and reliable electricity. The current component for the power system for OSI include diesel generators, UPS and hybrid power system that can accept power from other generation sources, such as solar. UPS systems...
The International Data Centre seismic, hydroacoustic and infrasound (SHI) reengineering project began in 2014 with the goal of creating modernized, open-source software for SHI processing, and improving maintainability and extensibility to the system. Since 2019, the project is under active development, and the current main area of work is the elaboration of a modernized station state of...
The Leo Brady Seismic Network (LBSN) is a small regional seismic network established in 1960 by Sandia National Laboratories to monitor US underground nuclear tests at the Nevada Test Site (now known as the Nevada National Security Site). Until the mid-1980s, data recorded by this network were telemetered as frequency modulated audio from each seismograph over telephone lines to a central...
The Geophysical Survey of the Russian Academy of Sciences and Michigan State University are recovering, scanning, and digitizing the historic analog seismograms of Soviet Peaceful Nuclear Explosions (PNEs). The Soviet Union detonated 122 PNEs from the mid-1960s through the late 1980s. The PNEs were conducted in a wide range of geologic settings and geographic locations, thus representing a...
The Lawrence Livermore National Laboratory, Michigan State University, and NDCs in Central Asia (Kazakhstan, Kyrgyzstan and Tajikistan) digitized seismic bulletins of analog stations between 1951 and 1992. The metadata of all seismic stations of that period were also collected. The national network bulletin data were then combined with the International Seismological Centre bulletin to form...
Revalidation of International Monitoring System (IMS)stations is a rest assured approach to demonstrate compliance with IMS minimum requirements for stations that underwent major upgrades or equipment changes that have caused station response modification. The Configuration Management Board (CMB) decides on the
need for the station revalidation after the case submission to CMB by IMS...
Scheduled calibration activities at International Monitoring System (IMS) seismic, hydroacoustic T phase and infrasound stations are part of the quality control requirements defined in the draft IMS seismic, hydroacoustic and infrasound Operational Manuals. Depending on the technology used, the approach for scheduled calibration can be different in some aspects. However, the overall objective...
Innovative deep ocean monitoring technologies are crucial to catalyzing fundamental improvements in mitigating natural disasters, reducing human vulnerabilities, and determining environmental threats. An attractive but untapped resource is the global submarine fibre optic cable network, which carries over 95% of international internet traffic. Key components of undersea fibre optic cable...
At the present moment, for many regions of the world, one of the topical issues is the prediction of industrial blasts seismic effects on the infrastructure and adjacent settlements. The IGR conducts this kind of work using the historical records of explosions and description of its effect on constructions as well as using the data of field experiments on mining explosions recording at the...
One of the most valuable sources for ground truth events are peaceful nuclear explosions as these were conducted in different geological environments on a vast territory. Temporary stations were deployed very often to record these events, and, in addition, in recent years work on the precise coordinates using contemporary methods was conducted. Using the records of historical analog...
During the past decades, Air Force Technical Application Center geophysicists, recognizing the importance of preserving analog historic data, have led various internal efforts to rescue and preserve legacy geophysical records. We will discuss the efforts and approaches we use to collect and integrate historical nuclear explosion data into our systems and to leverage its use to support our...
The Meteorology, Climatology and Geophysics Agency (BMKG) is a government agency that has the task of providing data and information services for meteorology, climatology and geophysics as well as delivering information to the public and related agencies. BMKG empowers and relies on the VSAT network which works 24/7. The BMKG VSAT communication network is a system that connects all systems...
The emerging technologies of Li-Ion batteries offer new design possibilities for remote monitoring station power supplies. Based on recent installations and testing of these batteries and complementary equipment, the Engineering and Development Section of the
International Monitoring System Division presents the results of both field and desktop studies, describing the advantages and...
The “Waveforms From Nuclear Explosions (WFNE)” repository was developed and is maintained by Leidos under DTRA sponsorship. It was built as a trusted data set, starting from the previous data repository “Nuclear Explosion Database (NEDB)” that was accessed in the past by numerous users in the US and international nuclear explosion monitoring community. WFNE includes detailed information...
The International Data Centre (IDC) is using critical and complex systems with several distributed processes for receiving, processing, disseminating and archiving data and products. A dedicated tool called WorkFlow is used, among other tools, to monitor those systems. The tool is only available in Linux machines, uses intensive database resources, is hard to maintain and requires expertise...
CTBTO is hiring professionals in STEM fields – Learn about CTBTO’s Recruitment Process
Come and find out more about how to join the CTBTO! Visit us at the HR booth and speak with the CTBTO Human Resources team and learn more about CTBTO careers. You can also join us in our HR presentation where we will walk you through our recruitment process. CTBTO is hiring top talent across a wide variety...
Activity ratios of CTBT-relevant isotopes can be used to discriminate nuclear explosion sources from releases of nuclear facilities and to determine the detonation time under assumed scenarios. The net signals of radioxenon isotopes and their associated uncertainties are estimated by the net count calculation (NCC) method. An alternative approach is the regression analysis such as the least...
The radioxenon system gain stability is critical to provide accurate measurements of the activity. There are several different methods for processing daily quality control (QC) beta-gamma two-dimensional (2-D) spectra for checking energy calibration. Fitting to a template seems the most correct method for monitoring the calibration stability. The possibility of using a template for a 2-D...
In this study, we develop a new radioxenon detection system based on beta-gamma coincidence to improve the sensitivity of detection in laboratory analysis. The designed system is a new prototype that is tested by injecting the 222Rn and its daughters (214Pb and 214Bi) as a beta–gamma emitter and also Xe-131m gaseous sources, which are in the interest of CTBTO. Further, the system is calibrated...
One of the main challenges for the Comprehensive Nuclear-Test-Ban Treaty Organization verification regime is to be able to discriminate anomalous signals generated by underground nuclear explosions (UNEs) from those generated by other sources like medical isotope production facilities (MIPFs) and nuclear power plants (NPPs). The general method can consist in a procedure starting with the...
Atmospheric aerosol collection using electrostatic precipitation (ESP) promises power consumption roughly one order of magnitude lower than filter paper based collection methods. For monitoring radionuclides in the atmosphere, this translates to an order of magnitude improvement in system sensitivity for the same power consumed. Conversely, small portable systems are enabled with lower battery...
Creare has designed, built, and tested an electrostatic precipitator (ESP) collection system for integration into the next generation of monitoring stations, RASA 2.0. The new system design has several significant improvements including advanced detectors, increased particle collection efficiency, lower power consumption, and potentially shorter collection times. Our advanced two stage ESP...
The radionuclide network of the International Monitoring System (IMS), operated by the Comprehensive Nuclear-Test-Ban Treaty (CTBT) Organization, is comprised of particulate and noble gas analysis. A variety of spectroscopic techniques have been developed and are in use to identify radionuclides which may be indicative of a nuclear explosion. Ongoing efforts to increase the sensitivity of...
Recent developments of noble gas systems include new detector technologies. They exhibit very low background count rates. In this case, radioxenon signal as low as a few counts per day is expected. Therefore, for such low count measurements, classical Currie law estimation for measurement detection threshold and detection limits are not accurate enough. In this context, the CEA/DAM implemented...
Xenon spikes measurement is a key factor for Xe equipment calibration and a quality assessment/quality control programme for noble gas cluster. It is very important to have four Xe isotopes at the spike samples (Xe-131m, Xe-133, Xe-133m, Xe-135). The spikes are produced by contractors organized by the Comprehensive Nuclear-Test-Ban Treaty Organization. Unfortunately, due to very short half...
There are several methods for analysis of radioxenon beta-gamma coincidence spectra. The most important approaches to estimating the activity using beta-gamma coincidence spectra are the Net Count Calculation (NCC) and the Standard Spectrum Method (XeMat and ROI simultaneous fitting method). Within these approaches, algorithms differ in many ways and can provide different estimates of the...
Recent reports have shown that unusual xenon radionuclides can show up in grown based xenon detection systems that lead to false hits on all four of the regularly monitored radionuclides (Xe-135, Xe-133, Xe-133m, Xe-131m). Potential sources of these unusual radionuclides could be high flux neutron sources or spallation neutron sources that are operated in the vicinity of current ground based...
The CTBT-relevant radionuclides were selected using decay data from around 1998 to 2000. Now, about 22 years after the selection, we have available evaluated decay data that are even more reliable than they were at that time. The latest evaluated decay data (half-lives, decay modes, γ-ray energies, and their emission rates) for the CTBT relevant 96 radionuclides and background 49 radionuclides...
Gamma-gamma coincidence techniques are known to improve the detection of particulate radionuclides relevant for Treaty monitoring purposes. To that end, Pacific Northwest National Laboratory (PNNL, USA) has developed a novel γ-γ coincidence analysis and radionuclide quantification software package. The software’s execution has been tested for radionuclides relevant to Comprehensive...
Field studies of underground gas migration are an essential component of ongoing research to better understand how radioactive materials produced from underground nuclear explosions transport through and escape from the subsurface. Considerable research has been made in the past on understanding long term gas migration behavior driven by natural processes at field sites, but in recent years a...
As the new generation of International Monitoring Systems (IMS) stations radioxenon are being deployed, the radionuclide laboratories are seeing an increase in samples sent for reanalysis. These samples include both radioxenon spikes and environmental backgrounds. Additionally, the sample volumes have increased with the new systems to further improve the minimum detectable concentrations. We...
The purpose of a radionuclide expert technical analysis (ETA-RN) is to assist States Parties to identify the source of a specific event. The output of an ETA-RN is a State Requested Methods Report (SRMR), which builds on routinely generated results from standard International Data Centre products like the radionuclide reviewed report and radionuclide laboratory report. The various...
A new goal for radionuclide monitoring is inspired by what is done with waveform processing, to automatically create a radionuclide event bulletin, synthesized from multiple measurements across the radionuclide network. Network measurements are sequentially processed through detection, association, and finally assimilated in an event, which is then documented within a bulletin with supporting...
A methodology of particle grouping based on a mathematical model enables to induce manipulation of the particle size distribution using grouping and coagulation which leads, in turn, to the increase of filtration efficiency and detection ability of monitoring systems.
This study was conducted as a combined theoretical and experimental one. The current prototype consists of an inlet of...
Fires are still a large concern in several countries due to the social, environmental and economic damages they cause. Computer vision is focusing a lot of their attention on improving object detection as one of the fundamental challenges in the field. The aim of this research is to propose a system to predicate or to detect a fire accident in an on-site inspection area in real time using a...
The CTBTO International Data Centre (IDC) developed a novel Geant4 based Monte Carlo simulation software for HPGe detectors in use at particulate systems of the International Monitoring System (IMS). The software, dubbed GRANDSim (an acronym for Geant4-based RAdioNuclide Detector Simulation tool), allows to simulate both coaxial and planar detectors, and includes default definitions of...
One of the most important issues in radionuclide monitoring technology is the analysis of radionuclide data of the International Monitoring System (IMS). The number and concentration rate of CTBT-relevant detected radionuclides determine the possibility of a nuclear event occurrence in radionuclide monitoring. Fission and activation products being on the standard list of CTBT-relevant...
GBL15, the UK’s noble gas certified Comprehensive Nuclear-Test-Ban Treaty Organization's radionuclide laboratory, supports the International Monitoring System (IMS) through the measurement of environmental radioxenon samples using beta-gamma coincidence spectrometry. GBL15 currently utilizes a system comprised of NaI(Tl) photon detectors and plastic scintillator electron-detectors in a SAUNA...
An important aspect of on-site inspection (OSI) is a rigid chain of custody, where the risk of human error is minimized. Since 2016, FOI has conducted four field campaigns in Kvarntorp (Sweden), with the aim of understanding the radioactive xenon background in uranium-rich soil. During these campaigns, we have developed methodologies for sample collection and analysis. During the most recent...
A chain of custody (COC) is required in many laboratories that must analyse forensic materials and also to assure reliability of reported results. Tracking a reliable COC during an on-site inspection can be laborious but it is mandatory as it must assure that the evidence is authentic and traceable. The sampling methodology of the material, its transport and all the analysis steps as well...
Samples from International Monitoring System (IMS) stations which contain multiple CTBT-relevant radionuclides with abnormal activity concentrations (Level 5 for particulates) are sent to IMS radionuclide laboratories for further analysis. Since a reanalysis of spectra at IMS radionuclide laboratories might enhance the reliability of analysis results, it is proposed to investigate a method...
For the enhancement of International Data Centre products, specifically, the Standard Screened Radionuclide Event Bulletin (SSREB), an important step is to establish methods to associate the detections of CTBT-relevant nuclides in different samples with the same release to characterize its source for the purpose of nuclear explosion monitoring. Episodes of anomalous activity concentrations at...
The isotopic ratios of radioxenon can be useful for discrimination between CTBT-relevant radioxenon detections and civil nuclear facilities. In this presentation, the isotopic ratio distributions of emissions from the civil nuclear facilities, are evaluated first in order to test and demonstrate this methodological approach. Second, the source-receptor sensitivity fields calculated...
Environmental radioxenon measurements for nuclear explosion monitoring use the net count method to determine activity concentrations and rely on detector sensitivities for each of the radioxenon isotopes. This method requires that a detector background measurement be made to account for environmental radioactivity and is only performed during the initial install or during a recalibration....
The ability to evaluate the concentrations of radioactive noble gases in the atmosphere is very important because it represents a powerful early warning tool in the event of a nuclear accident. Since there are currently no laboratories capable of carrying out this type of assessment in our country, a specific system has been set up for sampling, concentration, separation and analysis of...
Recent studies emphasize neutron activation as a source of radioxenon emission which needs to be considered as contributing to the atmospheric radioxenon background. Since activation products have different isotopic ratios than radioxenon from fission, taking activation into consideration impacts on the determination of the origin of radioxenon detected by the International Monitoring System....
Radioxenon is used to identify underground nuclear explosions by quantifying the amount and isotopic ratios of Xe-135, Xe-133, Xe-133m, and Xe-131m. Determining these concentrations requires knowledge of the detector performing the measurement and the accurate attribution of each measured decay. The current standard for estimating the activity concentration employs a beta/gamma coincidence...
Operated by the Comprehensive Nuclear-Test-Ban Treaty Organization, the International Monitoring System is used by almost 200 nations to monitor for nuclear weapons tests. After more than 20 years, the network is mostly complete, however the technology utilized for the particulate monitoring component remains practically the same, despite a number of laboratories developing coincidence systems...
This work presents the results of the development and experimental investigations of the sampling unit of the automated system for monitoring the Ar-37 content in the soil and the surface atmosphere. The adsorption and separation characteristics of materials for air separation and argon extraction from an air sample by the volumetric method have been studied. CaA (5A), PSA/VPSA (13XHP) NaX...
An on-site inspection (OSI) could be triggered in any environment. Environmental factors affect not only the signatures and observables of a nuclear explosion, but also the performance of the inspection team. Pursuant to the work on the OSI Action Plan 2016-2019 Project 1.5 on Operationalization of OSIs in Different Environments, this poster summarizes typical nuclear test explosion scenarios,...
Radiation early warning systems (REWS), which continuously transmit information about the level of radiation background, volumetric activity of radionuclides, meteorological conditions and other measured parameters to the central control post, can significantly reduce the risks of radiation threats to the population in controlled areas. The structure and composition of the existing REWS in...
Measuring radionuclide releases from underground nuclear explosions is extremely challenging given the likely low release and increasing background releases. This becomes even more challenging when measurement uncertainties are not fully understood and can make decisions based on measurements questionable. The work presented here will lay out a holistic uncertainty model that includes terms...
Lessons learned from 20 years of operation of the International Monitoring System for aerosol sampler/analysers have pointed the way to a new generation of aerosol monitoring equipment. Using new technology and following the sampling/analysis scheme developed for next generation xenon systems, new aerosol equipment will be more resilient in power failures, will give much better location in...
Isotopes of radioxenon are prevalent in the atmosphere and present a “background” signal which can make radioxenon detection analysis and event reconstruction analysis more difficult. In recent years advances in software have allowed for Bayesian reconstruction techniques to be applied to radionuclide detections to determine the source parameters. This work focusses on the effort to...
Sonicona was contracted by the CTBTO to explore processing methods for the development of on-site inspection resonance seismometry capabilities. The motivation is to analyse seismic earthquake recordings to detect any anomalies indicative for a cavity or rubble zone caused by an underground nuclear explosion. We have developed the onset-delay method for strong earthquakes from regional to...
The world´s first radioxenon array has successfully been installed in Sweden. The array consists of five detecting sensors (SAUNA Qb) which have been in operation for about two years. Compared to other radioxenon systems, the units are less expensive and easier to install and maintain. The cost of the entire array is similar to one single state of the art system. The individual sensors are...
A SAUNA xenon lab system is operated at the Swedish xenon laboratory. The system has been running since 2009 and is used for a large variety of samples, ranging from subsoil samples with stable xenon volumes as low as 0.1 ml up to samples from the SPALAX-NG systems with a xenon volume of up to 6 ml. The high dynamic range of sample sizes puts special demands on the performance stability and...
The International Monitoring System radionuclide particulate systems of the CTBTO network are equipped with one of the following three system types: CINDERELLA, RASA and manual. Each system commonly involves sampling, decaying and acquisition processes. Whereas the entire processes are automatically conducted in both the CINDERELLA and the RASA systems, ensuring high reproducibility of the...
Prior efforts in developing a silicon beta cell as a potential improvement to scintillating plastic in beta-gamma systems resulted in a design with high resolution, capable of resolving different conversion electron energies in the metastable radioxenons, but a higher threshold that cut off low energy X rays. Switching from a photomultiplier tube based NaI well detector to a low-voltage...
For the Source Term Analysis of Xenon (STAX ) project an experimental network to measure releases of radioxenon isotopes at the stack of nuclear facilities is being set up. The data are transmitted to a central server, where authorized users can retrieve raw data from the STAX server or can view the data via a web browser. In this presentation an overview on the various interactive data...
Noble gas processes are based on the use of adsorbent materials. Among them, silver-exchanged zeolites are the most efficient for Xe extraction. Before the use of a material in processes, it is crucial to ensure its performance, especially when use in systems operating 24/7. Ag-ZSM-5 (one of the studied exchanged zeolite) is an efficient candidate to enrich Xe, but long term stability seems to...
Normal operational releases of radioxenon make the discrimination between radioxenon detections from civil nuclear applications and from nuclear testing a very complex task.
The objective for the short to medium term is to develop algorithms and tools that facilitate the understanding of the background. The longer term vision is to eventually develop robust methodologies for explaining to...
Radioxenon monitoring systems are a crucial component of the International Monitoring System (IMS) for the verification of the Comprehensive nuclear-Test-Ban Treaty. They monitor the atmosphere for potential xenon releases originating from nuclear tests. The efficient collection and purification of xenon from air is essential for their detection capability. The first systems in the IMS used...
Xenon International is a next generation radioxenon monitoring system that was developed at PNNL and being manufactured at Teledyne Brown Engineering (TBE) to strengthen nuclear test monitoring and has recently completed Provisional Technical Secretariat (PTS) testing and was accepted as a qualified system for the International Monitoring System (IMS). Xenon International processes samples...
The CTBTO receives, collects, processes, analyzes, reports, and archives data from International Monitoring System (IMS) facilities and makes it available to authorized users. Automatic processing methods and interactive human analysis are done on a routine basis to raw IMS data in order to produce and archive standard International Data Centre products.
The primary purpose of the IMS data is...
In recent years, the connections between climate change and security have drawn a lot of scholarly attention. Climate change adaptation measures frequently fall short of completely integrating peacebuilding or conflict prevention aims, making already vulnerable communities further impoverished and less able to withstand interconnected climate and security problems. The CTBT, which promotes a...
The West African region has experienced devastating earthquakes in historical and recent times. The seismic activities with magnitudes ranging from 1.4 to 6.5 have been observed and recorded in the region. This includes the December 22, 1983, Mw=6.3, Guinea earthquake; 275 people were killed, more than 1000 were injured and 18,000 people were rendered homeless. The June 22, 1939 earthquake...
The purpose of the panel on “Introduction of professional networks promoting female and young experts in STEM and cooperation with CTBTO” is to introduce the audience to networks and activities that are represented on the podium and to inform about their CTBT-related activities supporting the engagement and integration of youth and female experts in the CTBT experts’ community.
There is no...
A success tsunami early warning issued to the public just after the occurrence of M7.5 earthquake located in the Flores Sea-Indonesia on 14th December 2021. Rapid seismological observation involving 6 CTBTO seismometers in Indonesia, 440 Indonesian Meteorology Climatology and Geophysics Agency (MCGA) broadband seismometers, 5 borehole seismometers and 167 neighboring countries seismometers....
National Data Centres are the national technical organizations competent in advising their governments on the verification of the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Between the mains elements of the NDCs highlight the waveform analyst staff, playing an important role in the CTBT's verification architecture. In this sense, its permanent training is key for the development of...
The 1st Nuclear Explosion Signal Screening Open Inter-Comparison Exercise 2021 was conducted from the end of 2021 to the end of 2022. The exercise evaluated different screening methods and procedures to identify radioxenon detections not consistent with the radioxenon background from civil nuclear facilities. It was based on a subset of a radioxenon test data set produced for the whole year of...
The aim of this presentation is to share experiences and lessons learned from our first year of operation. From build-up and establishment challenges, data products and reports, detection levels trends and data comparison betweenthe International Data Centre (IDC) and the National Data Centre for testing and capacity building purposes for analysis. Three radionuclide stations from Argentina...
Tsunamis have a long history of devastation, causing more than 250,000 deaths worldwide during the last two decades. Current rapid warning systems rely on the earthquake magnitude mainly resulting in over three-quarter of alarms being false. Aiming at reducing false alarms we have developed a complementary real time early tsunami warning system methodology. The methodology is based on...
Timor-Leste is a small country that lies along the Pacific Ring of Fire. According to Think Hazard, the entire country's exposure to earthquakes is high, which suggests that there is more than 20% chance of potentially-damaging earthquake shaking in the country in the next 50 years. Moreover, as a country surrounded by about 706 kilometres of coastline, it also faces the threat of tsunamis. In...
CTBTO has an active program for capacity building, to increase the ability of scientist and operators from signatory countries to process and interpret data. While most of the courses are carried out in Europe, a few regional training courses have proven to be excellent ways to integrate people from countries in that region. Increasing the number of these regional courses but also to having...
The geographical location of Bangladesh is at the northern most part of the Bay of Bengal having a funnel shaped ending at the southern coast. Tectonically, the region is at the junction of the Indian and the Eurasian plate making an active tectonic zone of the world. Therefore, possibility of earthquake in the ocean is likely to occur in any place of the region that can result to tsunami at...
The CTBTO operates a worldwide network based on four complementary verification methods to detect any sign of a nuclear explosion conducted anywhere – underground, underwater or in the atmosphere. The radionuclide technology is the only one that can confirm whether an event is indicative of a potential nuclear test.
The four CTBT-relevant radioxenon isotopes are fission products. They are...
Sudan has signed and ratified the Comprehensive Nuclear-Test-Ban Treaty (CTBT) on 10 June 2004, making Sudan 172nd State Signatory. The establishment of a capacity building system (CBS) in Sudan is helpful in integrating data acquisition, processing and analyzing using the NDC in a box. The different training courses and participation in workshop and conferences play an important role in the...
Meteoroids larger than about 10 cm in diameter produce shockwaves upon entering dense regions of the Earth’s atmosphere, where the local Knudsen number corresponds to the continuum flow regime. Shockwaves generated by the hypersonic flight and fragmentation of meteoroids decay to low frequency sound (infrasound). Given desirable propagation conditions and sensor availability, meteoroid...
More than ten years after its development, the inspection team functionality (ITF) has unquestionably become the conceptual framework adopted by the inspection team during on-site inspection (OSI) field exercises. The expectation is that ITF will successfully guide the inspection team when conducting an OSI once the Treaty enters into force. The concept forms the backbone of the inspector...
The CTBTO is setting up and operating a worldwide network of stations to monitor the globe for evidence of potential nuclear tests. Radioxenon plays a crucial role when determining whether an event is of CTBT-relevance. Specific measurement systems have been developed in the past decades and recently enhanced with a new generation of noble gas systems. Tailored analysis methods have been...
The 15 January 2022 Hunga, Tonga, volcano's explosive eruption produced the most powerful blast recorded in the last century, with an estimated equivalent TNT yield of 100–200 megatons. The blast energy was propagated through the atmosphere as various wave types. The most prominent atmospheric wave was a long period (>2000 s) surface guided Lamb wave with energy comparable to that of the 1883...
The Chernobyl and Fukushima accidents have shown that the so-called “co-expertise” process is an effective lever for empowering the people concerned in order to give them the means to make informed decisions concerning their own protection. In the event of an on-site inspection (OSI) under the CTBT, inspectors and support staff of the inspected State Party are likely to encounter radioactive...
Success of an on-site inspection depends largely on two factors: identifying the locations of interest within an area of approximately 1000 km2 and evaluating time critical signatures enabling pinpointing ground zero. Visual observation is the technology that has developed to identify locations of interest in rapid assessment manner. This process allows concentrating the inspection to...
The explosive eruption of the Hunga Volcano on 15 January 2022 provided an ideal test case for reviewing established methods to analyse source processes, especially because the key task of discriminating different kinds of explosive sources such as a nuclear test and a volcano eruption can be challenging. Standard techniques were applied to analyse critical events in the frame of the CTBT,...
A propagation model for atmospheric pressure signal generated by the eruption of the Hunga-Tonga-Hunga-Haʻapai volcano (hereafter abbreviated as Tonga) is proposed. The model is used to explain the changes in the wave form of the observed signal with increasing distance from the volcano. The model is based on the solution of the linearized Korteweg de Vries (KDV) equation, which describes the...
The GIMO platform facilitates the implementation of on-site inspection (OSI) search logic by providing the framework and tools to meet the requirements of inspection team and field team functionalities, and data flow. This paper reports on the various instances of GIMO developed to cater for requirements at the operational support centre, the base of operations, the inspection area – including...
A devastating earthquake doublet occurred on 6 February 2023 with moment magnitudes of Mw 7.9 and Mw 7.7 along the East Anatolian Fault (EAF) and Sürgü-Çardak Fault (SCF), respectively. The 2023 earthquake sequence resulted in catastrophic human life and economic loss, and caused major impacts to infrastructure throughout south-east Türkiye and north-west Syria. The kinematics of ruptures for...
Recent efforts have explored the use of high resolution beta detectors for improved metastable isomer discrimination. These detectors have been focused on implementation within the IMS stations for detection of all four radioxenon isotopes. The duration between collection and measurement is increased for radioxenon laboratories. Based on the shipping duration and sample type (spike versus...
Many different uncertainty sources can contribute to errors in the infrasound wave parameter (azimuth, trace velocity, amplitude) estimation. It is important to both understand how these sources can effect infrasound measurements, and how to minimize their effects on the infrasound measurements. One such a source is the detector, which comprises the wind noise reduction system and the...
Analysis of the seismic data quality provides a vital tool to identify seismic station problems. Timing accuracy, completeness, and ambient noise levels are considered as key data quality parameters. Variation in seismic station noise level and their deviation from a global noise model affects the capability of seismic event detection. Microseismic noise at a station is expressed by the power...
Beta-gamma coincidence method are used to detect and measure radioxenon isotopes in the field, greatly reducing the background and increasing sensitivity. Research has been performed to explore further background reduction using spatial information provided by pixelated, voxelated, or segmented detectors. This includes segmented and pixelated silicon detectors for the beta or electron...
The 15 January 2022 volcanic eruption of Hunga, Tonga produced atmospheric waves that astonished both scientists and the general public. These waves were observed globally by a multitude of instruments and technologies and were nearly ubiquitous across the IMS infrasound network. The most notable atmospheric wave was the Lamb-wave, which is an acoustic-gravity wave that is associated with...
In 1957, the international geophysical year, the very first seismic station was installed in Mongolia and seismic monitoring started from then on. The Mongolian Seismic station number of IAG of MAS has been increasing year by year, especially in the last 10 years after the transition to a digital station for the old seismic station. In 2013 new stations, such as eight broadband stations, five...
This study describes a new technique of 4πβ-γ detection system to perform primary methods for the measurement of activity of radionuclide. Characterization of the detectors, plastic scintillators for β-detector and a NaI(Tl) detector for γ-detector, has been investigated by using Monte Carlo GEANT4 simulation and experimental measurement. In addition, an optimum configuration of plastic...
The primary seismic network of the International Monitoring System (IMS) forms the backbone of the CTBT verification regime. Consequently, the performance of the network needs to be documented. A key parameter in this respect is the event detection threshold which can vary significantly with time during situations such as high station noise levels, large earthquakes or outages of key stations....
The 15 January 2022 eruption of Hunga Tonga-Hunga Ha’apai in the Tonga Islands was unprecedented in modern times. It was one of the largest volcanic explosions of the instrumented era and ranks as the most energetic volcanic explosion on Earth since the 1883 eruption of Krakatau (Indonesia). With its ash plume reaching high altitude, an intense volcanic lightning storm, atmospheric waves...
The geophysical instrumentation of the CTBT worldwide is important for characterizing nuclear and chemical tests. These observatories have also strengthened the geophysical monitoring capabilities of solid-earth processes like large earthquakes and volcanic eruptions on Earth. However, assuring the correct functioning of this instrumentation is hard under extreme conditions of temperature,...
The article explores the possibility of applying the mathematical framework to map the radiation field transmission zone in the area of nuclear tests, as well as the visualization of the built model using virtual reality technology. In turn, the possibility of applying the calculus to study the accumulation of fissile materials in the zone of a supposed nuclear explosion is considered. The...
In Indonesia, the CTBTO auxiliary seismic station network consists of one data center (NDC-BMKG) and six auxiliary seismic stations. Each station is in a different environmental condition and faces a unique set of troubleshooting challenges. According to the incident's history over the last five years, power and on-site communication issues were prevalent. The implemented troubleshooting is...
Active seismic survey, together with aftershock seismic survey, magnetic and gravitational field mapping and electrical conductivity measurements (Protocol to the CTBT, Part II), are geophysical detection technology which can contribute jointly to the search logic for the detection of on-site inspection (OSI) anomalies or artifacts underground. This work presents a system solution to active...
Spot check is the final level of the interactive review hierarchy aimed at the improvement of Reviewed Event Bulletin (REB) quality. At the International Data Centre (IDC) this task is conducted by an independent reviewer whose responsibility is to investigate event location anomalies, missing or bogus large events representing invalid data associations or incorrect detections. To facilitate...
IS42 was certified on December 2010 and is one of the infrasound stations of the International Monitoring System (IMS) of the Preparatory Commission of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO). The station is installed on Graciosa Island (Azores archipelago, Portugal), in the North Atlantic Ocean. The layout of eight array components together with its geographical...
In explosion monitoring, seismic arrays offer significant signal to noise improvements and enhanced ability to detect and locate important events. This advantage can be significantly degraded, however, in the presence of noise on the array components. For automated processing methods, this may result in a failure to identify an important signal, since many methods use thresholds. For a chronic...
Seismic signal detection and phase arrival picking had been initially carried out manually by qualified analysts. Currently, the introduction of large digital seismic monitoring networks has led to the necessity of automatic detection and picking tasks. The latter are extremely important, not only because an earthquake or a nuclear explosion must be detected and located automatically, but also...
Array processing is routinely used to measure apparent velocity and back-azimuth of seismic arrivals at the International Data Centre and many National Data Centres. Both quantities are measured under the plane wave assumption and are used to classify the phase type and to determine the direction towards the event epicentre. However, structural inhomogeneities can lead to deviations from the...
The International Data Centre (IDC) estimates several types of seismic magnitudes. Two of them are: the body wave magnitude mb, and the surface wave magnitude Ms. Both measures are significant to the CTBT verification regime as an input for discrimination methods between earthquakes and explosions, while mb is used for yield estimation for a presumed explosion. The IDC, like other institutes,...
This paper summarizes the advances in the application of machine learning to seismic monitoring data processing. Then it focuses on our work including local events detection based on multi-task Convolutional neural network (CNN), Generative Adversarial Network - Long Short-Term Memory(GAN-LSTM) joint network applied to seismic noise signal recognition, the seismic phase sequence detection...
All States Parties have convenient access to all International Monitoring System (IMS) data, International Data Center (IDC) products and all applications and scientific studies programmes used in the IDC of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO). We took advantage of this as the Iraqi National Data Center. in this study most of the research and studies related to the...
The Sliding Information Distance (SLID) metric is a compression based metric that can identify signal arrivals in seismic data. SLID has advantages over existing algorithms that are used for detecting arrival times because it can be used to calculate the certainty of each automated detection and to denote multiple possible arrival times in cases where the detections have low certainty. This...
In this continuously globalized world with its vulnerability in the event of deployment of nuclear weapons in conflicts, testing of nuclear device appears to have assumed a redefined aim far beyond the traditional conceptualization. This new function can be seen in the context of recent nuclear device tests by Democratic People Republic of Korea (DPRK). Nuclear device test scholarship has been...
We present results from our use and analysis of the most recent release of NIAB, which contains the NET-VISA associator integrated into SeisComp3 (SC3). This version allows for the configuration of non-International Monitoring System (IMS) stations using both the International Data Centre (IDC) DFX detector and NET-VISA. Non-IMS stations from the Australian network and from other regions of...
PhaseNet and EQTransformer are two deep learning methods most commonly used for automatic earthquake detection and phase-picking. This work presents the performance of these algorithms using two weeks of data retrieved from the Botswana Seismological Network stations. Additional data used is obtained from the International Monitoring System network within a distance of 250 km from Botswana...
The infrasound array in Hungary at Piszkés-tető (PSZI) has been collecting data since 2017. For signal processing, the Progressive Multichannel Cross-Correlation (PMCC) method is used, which resulted in about a million detections so far. Among these detections there are about 10 000 categorized, hand labelled events from quarry blasts, storms and power plant noise that constitute the dataset...
Seismic waves are emitted by events such as earthquakes, explosions, or other movements of materials within the Earth. The International Monitoring System comprises of a global network of seismic stations intended to identify and locate such events. The accurate estimation of the back-azimuth, or the angle of arrival, of these seismic signals remains a key challenge. Over the last decades,...
Seismic events are produced by different types of sources (e.g. local earthquakes, distant earthquakes, quarry blasts, nuclear explosions, volcano activity, etc.). These events are detected by seismic network stations and stored. The first important task in seismic signal processing is to identify the source of each detected event. This task should be performed automatically due to the large...
Seismic waveform data are generally contaminated by noise from various sources, which interfere with the signals of interest. In this study, we implemented and applied several noise suppression methods. The denoising methods, consisting of approaches based on nonlinear thresholding of continuous wavelet transforms (CWTs), convolutional neural network (CNN) denoising and frequency filtering,...
Indonesia’s active involvement in nuclear politics can be traced back to the preparation committee for the establishment of the International Atomic Energy Agency (IAEA). During its first decade of Independence, the Government of Indonesia (GoI) elaborated its international politics of non-block by becoming a member of IAEA notwithstanding the high cost effect of the membership. Supporting...
Discriminating the event type with seismic waveforms is a vital part of the verification work. In this research, 500 seismic events with a magnitude below 3.0 ML around Beijing were collected in the categories of: natural earthquake, blasting and mining collapse. More than 25 features and their ratio parameters were applied to characterize the seismic waveforms, which were extracted from P ...
An effective response to the threats and challenges of the 21st century can only be achieved through the coordinated efforts of the international community, through the UN and international law. Although the role and significance of the CTBT cannot be overestimated, this role has been hampered due to the inability of the CTBT to enter into force, because ratification by eight Annex 2 states is...
The CTBTO releases the Standard Events Lists (SELs) with information about the location, magnitude, time and depth of events identified from the automatic analysis of waveform data (seismic, hydroacoustic and infrasound). This automatic generated list of events could be evaluated using machine learning methods. Machine learning models work in two phases; training and testing. The training...
Seismic noise from a variety of nuisance sources frequently contaminates signals of interest. Effectively suppressing this noise is a crucial step in the processing pipeline. In a previous work, Tibi et al. (2021) developed a seismic signal denoising approach that uses a deep convolutional neural network (CNN) model to decompose an input waveform into a signal of interest and noise. While...
This work expands on a new method, called event-based training (EBT) which is primarily a tool to leverage large datasets with little or no ground truth, to build event discrimination models across the continental United States. We include data from the transportable array and other regional catalogs as well as including a null criteria to enable a model to abstain from decision making in the...
The International Monitoring System includes waveform sensor stations connected to a centralized processing system in the International Data Center. Recent tools at the IDC use Bayesian analysis to detect and localize seismic events, such as NET-VISA. While the Bayesian approach to seismic monitoring can improve significantly on the performance of classical systems, this approach needs prior...
The range-dependent Acoustic Model (RAM) is a prevalent underwater acoustics modelling program, which employs a 2-D parabolic equation method. Parabolic equation is known as an accurate and reliable method, and it has been extensively used in the underwater acoustic community. Even though the parabolic equation method requires less computation resources than many other methods, an efficient...
The Comprehensive Nuclear-Test-Ban Treaty (Treaty) of 1996 obliges its signatories not to undertake nuclear weapons tests. Kenya is a signatory to the Treaty and operates an infrasound and a primary seismic station in Nairobi. The city has a 2.8% urban growth rate and in 2019, its population was 4.3 million. An increase in anthropogenic activities directly impacts the International Monitoring...
We train deep learning models for seismic detection on 3-component stations from the International Monitoring System (IMS) based on PhaseNet architecture and evaluate the results using the Unconstrained Global Event Bulletin (UGEB). Using 14 years of associated signals from the Late Event Bulletin (LEB), we auto-curate a training data set consisting of signal windows containing associated...
From 2000, when official bulletin production at the International Data Centre (IDC) of the Provisional Technical Secretariat (PTS) started until 2012, comparisons of the Reviewed Event Bulletin (REB) with the Published Bulletin of the International Seismological Center (ISC) had been carried out. As numerous efforts have taken place since then, such as enhancing the automatic as well as the...
The first step in most seismological studies is detecting seismic events. Due to attenuation law, the interstation spacing of seismic networks plays a fundamental role in the capability of phase detection, so the inappropriate density of seismic stations reduces the detection capability. The immediate solution to this problem is to increase the density of stations. But, this is too expensive...
The objective of this study is to improve modeling underwater ambient noise below 100 Hz from local and distant wind. Historically, shipping is assumed to dominate ambient noise at this frequency band, however, the CTBTO hydroacoustic array off Crozet Island provides unique wind noise observations with minimal shipping interference. First, ambient noise is correlated to overhead windspeed...
This study presents a new method based on wavelet transform for moment tensor inversion. The method consists of a semi-automatic data preparation and source inversion prepared in python. The procedure is similar to the point source technique in the time domain but is adjusted using wavelet coefficients. The advantage of our algorithm is to test the centroid moment tensor in all frequency...
NET-VISA is a Physics-Based Generative Model of global scale seismology. The model includes a description of the generation of events which include underwater and atmospheric events, the propagation of waveform energy from the events in multiple phases, and the detection or mis-detection of these phases at the network of stations maintained by the International Monitoring System as well as a...
Nuclear justice associated with the humanitarian consequences of nuclear explosions has become a prominent issue in the broader nuclear weapons discussion since the 2010 NPT Review Conference when States Parties expressed their “deep concern at the catastrophic humanitarian consequences of any use of nuclear weapons." Notably, the term “nuclear justice” within this work exclusively refers to...
In this paper we conduct a study of on-site estimation of the time of arrival (ToA) strongly distorted acoustic signals. Propagation of the acoustic waves from sources is controlled by a complex interplay between source location, winds, temperature, humidity, atmospheric attenuation, and topography, which are the main factors that lead to signal distortion. An algorithm was developed (usable...
CTBTO observation and processing systems are required to be sensitive to low magnitude events. A promising way to increase system sensitivity and improve station tuning is to refine the receiver velocity models underneath International Monitoring System (IMS) stations by incorporating a number of ambient noise processing techniques into the International Data Centre (IDC) practice. In...
This study aims to explore novel physics-guided neural network (PGNN) algorithms as applied to time-domain source functions (TDSF) of explosions for automated emplacement material classification as well as the estimation of yield (W) and depth of burial (DOB) in a regression formulation. We assume that explosions are detonated at the center of cavities embedded in an infinite homogeneous...
This study uses 48 000 synthetically generated time-domain source functions (TDSF) to illustrate the performance of newly developed physics-guided neural network algorithms for classification of the emplacement conditions in materials where the explosions are detonated. TDSFs were constructed at the elastic radii of many explosions for material properties representing the granite, shale,...
Detection, localization, and characterization of energetic events in the atmosphere and at shallow depth of burial using infrasonic signals is often performed via an automated pipeline framework with refinement using interactive tools for an identified event-of-interest. Recent updates to the InfraPy signal analysis software suite authored and maintained by infrasound experts at Los Alamos...
Automatic detection of seismic events in processing pipelines at the International Data Centre and many National Data Centres is mostly done using beamforming on arrays; however, extensive use of single stations can improve the detection capability and accuracy of event location. Advances in deep learning methods enable faster and more accurate processing of large quantities of single station...
This study reviews performance of NET-VISA in operations (vsel3) and results of a full pipeline test of NET-VISA from 2021 in comparison with SELs. NET-VISA performed better than the standard global associator, GA, however several differences in how these algorithms form events were identified. These differences provided fewer constraints in event formation for NET-VISA in comparison with GA,...
In seismic signal analysis it's crucial to be able to distinguish between earthquakes and underground nuclear explosions, which is an important component of the Comprehensive Nuclear Test-Ban Treaty Organization (CTBTO). Many methods have been used, such as the complexity, the spectral ratio, body wave and surface wave magnitudes (mb-Ms), and P and S corner frequencies. The data set of nuclear...
The classification of low magnitude seismic events is an important task in regional earthquake monitoring. This study focuses on the classification of earthquakes, explosions, and mining-induced earthquakes. A 36-dimensional feature extraction dataset was established through eight types of feature quantization methods, and two-classes and three-class models were respectively constructed by the...
Seismic event source identification using recorded signals could be a complex task to solve using classical mathematical methods. Alternatively, many recent research studies have opted for artificial intelligence techniques to deal with this classification problem. Indeed, artificial neural networks, particularly multilayer perceptron (MLP), are one of the techniques that have achieved good...
T waves signals at International Monitoring System hydrophone stations can present complex arrival characteristics caused by bathymetric features along their long range propagation paths through horizontal reflection, refraction, and diffraction. Thus, the interpretation of recorded T waves can be challenging due to differences in observed and expected arrival times, back-azimuths, or energy...
Large earthquakes and aftershock sequences substantially increase the burden of those who monitor seismic data for anthropogenic events. Fortunately, most aftershocks exhibit high degrees of similarity between their waveforms, making them well suited for detection and identification through waveform cross-correlation techniques. Such techniques pose some challenges, however, such as building...
NET-VISA is a Physics-Based Generative Model of global scale seismology. The model includes a description of the generation of events which include underwater and atmospheric events, the propagation of waveform energy from the events in multiple phases, and the detection or mis-detection of these phases at the network of stations maintained by the International Monitoring System as well as a...
We present an improvement to the multichannel maximum-likelihood (MCML) method. This approach is based on the likelihood function derived from a multi-sensor stochastic model expressed in different frequency channels. Using the likelihood function, we determine, for the detection problem, the generalized likelihood ratio with a p-value threshold to discriminate signal of interest and noise....
Studies on the CTBT universalization may benefit from understanding the social dimension of treaty ratification beyond techno-scientific endeavors. Within the emerging academic debate, the role of epistemic community, understood as a network of socially recognized experts in a highly technical issue, with the authority to translate scientific knowledge and social practice to certain policy...
The role of metrology in improving confidence in IMS measurements
Description: The purpose of this workshop event is to disseminate outcomes from the Infra-AUV project relating to the value of robust calibration practices in sensor networks and the associated practical aspects for maintaining sensor systems. The project will be producing a recommended good practice guide for establishing...
Engage with users of SHI NDC-in-a-Box to discuss recent developments and the future direction of development of all major components: Geotool, SeisComP and DTK.
Side event open to all participants.
In this study we present a method for comparing objects, identified on images acquired by the synthetic aperture radar (SAR). The method gives a quantitative value for the similarity of different objects, detected on the sea surface on SAR images. Aim is to track their changes and be able to identify the most similar pairs. As a case study we detect four rectangle-like objects north of the...
Atmospheric transport models (ATMs) are used to model the transport of radionuclides both to determine the origins of unknown releases and to model the background concentrations from known sources. To do this ATMs rely on meteorological information from four-dimensional numerical weather prediction (NWP) models. However, the chaotic nature of the atmosphere means that the meteorological...
Electro-optical satellite imagery provides analysts with opportunities to monitor suspicious nuclear activities in the restricted access area. The more remote sensing technology advances, the more resources available from both spatial and temporal resolution standpoints. Spatially, the area of interest that needs to be monitored by analysts has been detailed and accordingly increased;...
Beryllium-10, as measured in polar ice cores with an annual resolution, is a proxy for long term cosmic ray variability. Beryllium-10 concentration can not be used directly as a proxy for solar behavior since the signal can be distorted by atmospheric transport and deposition processes. The data on atmospheric Be-10 concentrations are rather scarce due to the laborious nature of Be-10...
The use of aerosol optical depth (AOD) has been proven as an alternative to the traditional ground level monitoring of air quality in many countries across the world. Therefore, this study based on MERRA-2 data aims: (i) to characterize the spatiotemporal and component variations of aerosols in the atmosphere over the capital cities (Luanda, Sumbe, Benguela, Huambo and Lubango) of the five...
This paper showcases the work done on the designing and the making of a bespoke readout circuit that reads and produces the measurements of a unique imaging system used to assay nuclear materials and hidden neutron and gamma emitting radionuclides. The system in itself uses neutron and Compton scattering simultaneously within three layers of detectors all baked with an 8x8 silicon...
With the development of commercial space technology, remote sensing for instance has been widely used in daily life. The availability of remote sensing images as commercially off the shelf products makes it possible for on-site inspection (OSI) application, especially for training courses and exercises. This work would carry out a commercial satellite imagery based information integration...
The Earth is continuously under the influence of solar radiation, which interacts with the Earth's magnetic field, causing various effects. One of them is the warming of the planet, keeping it in a suitable situation for the development and maintenance of life on Earth. Another is the bombardment of the Earth by plasma from solar storms, where the magnetic field acts as a protective shield...
CTBTO is hiring professionals in STEM fields – Learn about CTBTO’s Recruitment Process
Come and find out more about how to join the CTBTO! Visit us at the HR booth and speak with the CTBTO Human Resources team and learn more about CTBTO careers. You can also join us in our HR presentation where we will walk you through our recruitment process. CTBTO is hiring top talent across a wide variety...
In preparation of the next Integrated Field Exercise, and in line with the capabilities developed with past field exercises, action plan project and expert meetings, the section Equipment and Instrumentalization of the On-site Inspection (OSI) Division of the Provisional Technical Secretariat has entered into a new stage of development of its telemetry solution. In 2022, the existing data...
Wet scavenging is a vital process in atmospheric transport modelling to determine the distribution of masses. Therefore, using precipitation fields from the European Centre for Medium-Range Weather Forecast (ECMWF) data sets, which refer to a temporal integral rather than being a point value in time, as all other parameters in the Lagrangian dispersion model FLEXPART, is distorting the results...
A series of atmospheric transport experiments is being conducted to collect tracer data that will allow the refinement of meteorological models in complex terrain at short distances. Radiotracers were used to measure complex terrain flow features that influence diffusion and transport. Data were collected using an array of 22 real time radiation sensors dispersed over a 5 km region. Each...
In recent years, high altitude floating platforms with a microbarometer payload have been utilized towards infrasound detection and source characterization. The stratospheric locale is presumed to be less noisy, thus facilitating better signal detection compared to ground based sensors. High altitude sensing platforms are also considered the future of space exploration for extraterrestrial...
Knowledge about the natural background of xenon isotopes and Ar-37 in the top few meters of the soil column is crucial for the assessment of measurement of those isotopes in the course of an on-site inspection. There are many factors that control the Ar-37 concentration in soil air. Production and gas transport mechanisms have previously been investigated but less attention was put on the...
In February 2021, the Ukrainian small aperture infrasound array began recording in the Antarctic Peninsula area. This is a good step towards ensuring the implementation of the CTBT with national resources. However, only at the beginning of 2022 was it possible to organize continuous transmission of satellite data in real time. This made it possible to quickly track both regional events that...
A Field Test of on-site inspection (OSI) geophysical techniques for deep applications was conducted by the Provisional Technical Secretariat in September 2022 in the Austrian Ybbstaler Alps, with the support of external experts. The scope of the Field Test was to assess the current OSI geophysical imaging capabilities for deep applications in an integrated manner in a mountainous environment...
The Lagrangian atmospheric transport model FLEXPART is employed to investigate a broad spectrum of applications, including the transport of radioactive material emitted by nuclear events. Since its inception in 1998, FLEXPART has undergone many changes, with its last official release (version 10.4) published in 2019. At the same time, numerous versions have been developed across institutions...
There are two CTBT infrasound stations in Chilean territory, I13Cl and I14Cl, located respectively on Easter Island and the Juan Fernandez Archipelago. During the COVID-19 pandemic, a health alert was declared by the government to reduce the movement of people in Chile and thus avoid the spread of the virus to the islands. Due to this, a reduction in the local noise levels detected in these...
Microbarometer networks are in place for the detection of atmospheric infrasound waves and verification of the CTBT. The presence of turbulence and other wind-induced effects are considered a nuisance. For this reason, wind noise filters are typically in place for suppression. In this study, we establish a relation between microbarometer observations and in situ turbulence measurements at the...
Forensic seismology describes the detection and interpretation of exceptional seismic events, e.g. during an on-site inspection (OSI), or signals by plane crash, submarine explosion, bomb attacks. For basic research, forensic seismology means discovery of unknown or unexpected signals, e.g. precursors of rockslides, deep earthquakes below induced seismicity, or nano-earthquakes of active...
One of the most conclusive evidences of a violation of the CTBT is the presence in the subsoil air of elevated concentrations of Ar-37 radionuclide, which is formed in large quantities in the interaction of neutrons with calcium in rocks. Traditionally, to measure the activity of Ar-37, proportional gas counters are used, which are filled with a counting gas prepared from samples of argon with...
Based on the lessons learned during On-site Inspection (OSI) workshops; training courses and exercises, especially the Integrated Field Exercises (IFE); remotely controlled ground platform based geophysics detection systems, due to the practical application to hazard challenging conditions, would have their significance both for future real OSI activities and training courses of current stage....
The local active fault in Bali has a small magnitude (M<5) but has a destructive potential. This study used gravity data from GGMplus, topographic data from DEMNAS, and lineaments using ALOS-2 PALSAR-2 data. To identify the fault movement, we interpret the subsurface using the gravity derivative method. Identification of fault locations using lineament extraction from SAR data has been done by...
Results of a geothermal research project aimed to model structural controls of a geothermal reservoir located in the Kenyan Rift Valley will be presented. The geothermal reservoir model developed through several modelling software, using reservoir parameters like rock types, permeability, porosity and pressure distribution obtained during exploration and drilling will be based on a wide range...
In 2021 the first layout and design of the next generation on-site inspection (OSI) field laboratory was presented (Poster 3.2 -691). It highlighted the requirements, the status and future improvements of the OSI field laboratory for the development of its capability to be rapidly deployed during a CTBT OSI. Here we present some of the improvements for the OSI field laboratory, notably for the...
The objective of this paper is to demonstrate the use of the magnetic method in the on-site inspection (OSI) regime and try to find the best magnetometer for OSI applications. It will be used mainly to locate underground infrastructure. Theoretical and practical applications are used to give insight to the qualitative and quantitative information obtained from magnetic measurements. Also, the...
The Transient ElectroMagnetic Method (TEM) technique is one of the geophysical techniques used in on-site inspection. This work focuses on the mathematical and numerical modeling of this technique.
The numerical simulation made it possible to predict the response of the sensor. With the treatment of several underground configurations, the expert can acquire a good experience of...
The Wireless Independent Noble Gas Sampler (WINGS) is a mobile, modular gas sampling system designed for use in low infrastructure environments. WINGS units operate on battery power and communicate by radio connection. In the case of a suspected underground nuclear explosion (UNE), WINGS units could be deployed to detect and identify noble gases emanating from the explosion site or identify...
Observational data on atmospheric-pressure variations at the land surface have been obtained at the network of four microbarographs located in the Moscow region and processed. The analysis of data has made it possible to determine the characteristics (coherence, azimuths, and propagation velocities) of the basic arrivals of acoustic gravity waves from the atmospheric storms within a wavelength...
During search logic, the technique of environmental sampling can play a role in narrowing down the areas of interest and prioritizing the field mission. One methodology to achieve this purpose is to collect several samples from the same search zone and screen out any anomaly in the gamma spectra of the samples. To ensure a high throughput screening process it can be useful to gang the samples...
Simulations of atmospheric transport and dispersion have been demonstrated to benefit from a multiscale modeling approach that resolves both mesoscale meteorology, such as frontal passages, and microscale meteorology near the plume source, which can be heavily influenced by complex (i.e. mountainous) terrain. The atmospheric modeling community has yet to settle on recommended best practices...
In the case of an underground nuclear explosion, Ar-37 and Ar-39 are produced in rocks by neutron activation of Ca and K, respectively. Because of the very different half-lives of Ar-37 and Ar-39, the Ar-37/Ar-39 ratio in the subsurface is a function of the timing of production (pulsed vs. continuous), depth-dependent production mechanisms, and the Ca/K ratio of the rocks. The Ar-37/Ar-39...
The shape of radioactive particles varies significantly, 'from compact small-sized crystalline single particles to large amorphous aggregates' (Salbu and Lind, 2005). However, many atmospheric transport models assume perfect spheres. Since non-spherical particles experience a larger drag in the atmosphere, i.e. reduced gravitational settling, the atmospheric residence times and transport...
This paper presents the features of an innovative portable radioactive isotope identifier for the detection and identification of both gamma and neutron emitting radionuclides, or even multiple ones. The described portable isotope identifier is suited for the site inspection for its capabilities of detecting and characterizing nuclear or radioactive materials in presence of gamma shielding...
Atmospheric transport modelling (ATM) tracks the movement of released substances into the atmosphere. Dispersion of freshly emitted releases takes time to evolve, and the initial transport pathway depends strongly on surrounding conditions, such as wind patterns. Global ATM with reasonable coarse resolutions can usually reflect synoptic patterns, such as frontal systems. However,...
A gas sampler system has been designed, built, and deployed that may contribute to the near-field detection of underground nuclear explosions. The system is inexpensive, portable, and autonomously collects samples for subsequent lab analysis. Collection duration and interval parameters can be adjusted using Wi-Fi or other communications network based on the intended collection site....
The International Atomic Energy Agency Department of Safeguards deployed the Geo-based Data Integration (GDI) platform for information integration, analysis, and activity planning involving geospatially-related information used for nuclear safeguards verification. GDI provides interactive, layered maps in a secure, user-friendly collaborative environment for IAEA inspectors, analysts and...
Explosive volcanic eruptions produce powerful infrasound that can propagate thousands of kilometers in atmospheric waveguides. The International Monitoring System (IMS) infrasound network has now captured numerous acoustic signals from explosive volcanic eruptions. Remote infrasound has proven useful to locate and characterize subaerial volcanic source parameters (e.g. eruption chronology and...
The on-site inspection (OSI) is the final component of the Comprehensive Nuclear-Test-Ban-Treaty (CTBT) verification regime that will help determine whether a nuclear explosion occurred; facts may also be gathered to determine who was responsible for the Treaty violation. The techniques include ground based, airborne, and laboratory elements. Because technologies involving some of the methods...
We model the atmospheric transport of cosmogenic Beryllium-7 within the time period 1950-2100, to shed light on the complex interplay of atmospheric dynamics, changing atmospheric background conditions, deposition mechanisms and solar activity. Due to the short half-life of Beryllium-7 (around 53 days), the ground level concentration of this cosmogenic isotope is particularly suitable to be...
Infrasound technology has been employed to investigate acoustic signatures of severe weather events in the past and this study aims at characterizing, for the first time, the infrasound detections that can be related to Mediterranean hurricanes (Medicanes). These mesocyclones pose a serious threat to coastal infrastructures and lives because of their strong winds and intense rainfalls. This...
The use of remotely controlled platforms (RCP) during an on-site inspection (OSI) is an open topic, especially regarding aerial platforms. Such devices did not exist, or at least were not commercially available, when the Treaty was opened for signature and ratification, and therefore there is an ongoing debate regarding the conduct of inspection activities and health and safety related...
The importance of characterizing the amplitude and spatial variation of the geophysical anomalies created by on-site inspection (OSI) relevant observables is well known. By understanding such characteristics, it is possible to design the different geophysical surveys and to realistically assess the capability of a certain OSI technique to detect a potential observable. As part of the Action...
Infrasound propagation is mainly driven by the seasonal changes in stratospheric winds. However, small scale perturbations like gravity waves also affect the detection capability of the infrasound station network of the International Monitoring System. Simulations of atmospheric models explicitly resolving gravity waves are used to investigate the effect of these perturbations on infrasound...
Vertical profiles of particulate aerosols and meteorological fields were obtained before, during, and after the invasion of regional pollutants over the mid-hill Trishuli and Sunkoshi River valleys that encroach deep into the Central Nepal Himalayas. Particulate aerosols and met-sensors integrated unmanned aerial vehicle was deployed for the purpose. Probing up to 500 m above the ground, more...
NPE - independent performance assessment by multi-technological scenarios of potential CTBT violations.
Presentations and discussion coordinated by German NDC.
- Introduction and Overview - Purpose and Evolution of NDC Preparedness Exercises
- Review of the NPE 2019 Scenario
- Status and Plans for NPE 2023
- Discussion
The radioactive xenon isotopes Xe-131m, Xe-133, Xe-133m and Xe-135 are important indicators for an underground nuclear explosion. Knowledge about the concentrations and ratios of these isotopes that can be expected due to natural processes is important to be able to discriminate from a nuclear explosion during a CTBT on-site inspection. A series of measurements has been performed 2019 and 2022...
Radon is a naturally occurring radioactive gas produced as a decay product of uranium and thorium in geologic media. Radon is therefore a nearly ubiquitous gas background in the subsurface environment, as well as in many building materials derived from earth materials. In the context of nuclear explosion monitoring, radon as a background influences radiation detector sensitivities as an...
Noble gas systems at International Monitoring System (IMS) radionuclide stations used to operate with 24 or 12 hours sampling time. The next generation noble gas systems utilize shorter sampling periods. At station RN33 on Mount Schauinsland, Germany, a SPALAX system with 24 hours sampling is operated by BfS. A Xenon International system with six hours sampling time was installed in parallel...
Anthropogenic radionuclides have been injected into the atmosphere by nuclear weapon programmes, nuclear weapons testing, nuclear power plants and uranium mining. In this work, we considered the activity concentrations of anthropogenic radionuclides (Cs-137 and Cs-134) detected in the International Monitoring System (IMS) from January 2021 to December 2021. The main objective is to determine...
We are responsible for data analysis and management of radionuclide monitoring stations as the National Data Centre of Japan. There are two International Monitoring System radionuclide monitoring stations in Japan, at Takasaki for particles and noble gases and at Okinawa for particles. The detection frequency of Cs-137 is relatively high at both stations. In this study, we focus on Cs-137...
During the testing phase of the Xenon International radioxenon monitoring system in Knoxville, Tennessee, USA, there were observations of non-traditional xenon isotopes: Xenon-125, Xenon-127, Xenon-129m, and Xenon-122 (via the decay of Iodine-122). While the production mechanisms for non-traditional isotopes were hypothesized, it would be beneficial to perform a complete study on the...
Monitoring radionuclide concentrations is an important component of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) verification regime and can provide direct evidence of the nuclear nature of an explosion. Whereas, in the case of underground nuclear testing, the radioxenon isotopes have the highest probability of escaping into the atmosphere. Four of the xenon isotopes are of interest for...
As part of the Xenon Environmental Monitoring at Hartlepool (XENAH) collaboration, a team of scientists from the UK, US and Sweden have deployed three radioxenon sampling and measurement systems to the north of England, near to the Hartlepool Power Station. The power station comprises two 1600 MW(th) advanced gas-cooled nuclear reactors. The array of SAUNA QB (“cube”) radioxenon measurement...
The radioxenon signatures of 135-Xe, 133-Xe, 133m-Xe, and 131m-Xe are the expected and consistently observed radioxenons in the atmosphere. Testing of the Xenon International System at Knoxville, TN resulted in the detection of several previously unobserved radioxenon isotopes in the atmosphere 125-Xe, 127-Xe, 129m-Xe, and 122-Xe (via the decay of 122-I). These isotopes were periodically...
The Medical Isotope Production (MIP) by fission release radioactive noble gases into the environment.
These emissions increase the environmental background and could hinder the mission of the International Monitoring System (IMS) to detect early a nuclear explosion.
Argentina has been producing radioisotopes by fission since 1985 from the irradiation of Highly Enriched Uranium (HEU) targets....
A numerical study of conjugate flow, heat and mass transfer by natural convection of noble gases within an underground cavity partially filled with molten rock is presented. The molten rock is initially considered at rest at an initial temperature and concentration. The molten rock is viscous and possesses strength that is temperature- and crystal fraction-dependent. Under natural conditions,...
The backgrounds of radionuclides in the environment from natural and human made phenomena are well known to interfere with detection of nuclear explosions. International Monitoring System (IMS) stations perform measurements at ground level; however, little has been published regarding the vertical distributions of radionuclides expected from nearby and distant sources and if there is a large...
The Research Organization for Nuclear Energy analyses the dispersion of radioactive air release by using GENII V.2 software. The calculation of GENII V.2 has never been validated with the results of measurements directly and indirectly in the field. The validation of the GENII calculation of I-131 activity concentration was carried out by comparing the results of the GENII calculation of the...
The radioisotope Argon-37 is produced in underground nuclear explosions (UNE) through the neutron activation of Calcium-40 in rock and soil. A sensitivity study was conducted using Monte Carlo N-Particle Code (MCNP) and SCALE to model the predicted production rate of Argon-37 per kiloton explosive equivalent in various rocks following a UNE. The detonation was modelled in MCNP using a simple...
The radiological station located in Havana, Cuba will perform measurements for the International Monitoring System. The Turkey Point and Laguna Verde Nuclear Power Plants are potential sources of noble gases on a regional scale. The objective of this work is to identify the synoptic situations that would contribute to the transit of air masses coming from these facilities through Cuba. For...
This work describes a method for estimating the location, moment and the amount of an unknown atmospheric release of radioactivity, based on detections. First, the source location is estimated by a probability density function based on the time-integrated correlation coefficient between model calculations and measurements of radioactivity concentrations. Model results are calculated with the...
In the International Data Centre radionuclide pipeline, noble gas samples from the International Monitoring System (IMS) radionuclide stations are processed and categorized. The combination of multiple isotope observations of Level C plus prior/post Level B samples close enough in time, at one or more IMS radionuclide stations, forms decisive input for isotopic ratio analysis as these episodes...
An activity evolution model which goes from the release of an assumed underground nuclear explosion, through the atmospheric transport modelling (ATM), to sample collection and measurements can be used to link various quantities, including activities released from a nuclear event, activity concentrations in a plume over an International Monitoring System (IMS) station and activities collected...
Nuclear event radionuclide detection is the next step towards complementing data about any abnormal event recorded by seismic, hydroacoustic and infrasound station networks prior to asking for the approval of the on-site inspection (OSI). Radionuclides travel hundreds of kilometres away from their source under favourable meteorological conditions. In order to determine and assess anthropogenic...
The International Monitoring System (IMS) monitors compliance with the Comprehensive Nuclear Test-Ban Treaty (CTBT) using information collected by sensors (radionuclide, seismic, infrasound, and hydroacoustic) placed around the world. Sensors, however, give limited information; hence scientists at the International Data Centre (IDC) rely on data fusion and atmospheric transport modeling (ATM)...
It has previously been reported at Science and Technology conferences that PNNL has measured Argon-39 at historic underground nuclear explosion (UNE) sites at the Nevada Nuclear Security Site in gas samples from shallow (few meters or less) subsurface soil. Considerable Argon-39 was observed at UNE sites sampled. Thus, the detection of Argon-39 in such samples at strengths sufficiently above...
Exploding wires have been embedded in geologic matrices (concrete, basalt, sandstone, and granodiorite) to study explosive driven elemental diffusion and to elucidate the utility of elemental signatures. The exploding wire detonations have an input energy of up to 900 J equivalent to 0.22 g TNT. Simultaneous to the detonation, monitoring of the air concentration of elements was performed using...
Argon-37 is produced via neutron activation of stable argon or calcium in nuclear reactors. This isotope is used in on-site inspection (OSI) activities. Therefore, its background in the atmosphere from nuclear reactors is an important parameter in interpreting the OSI measurement results. Since its measurement is complicated, only few reports exist on the amount of its production in the...
Monitoring compliance with the Comprehensive Nuclear-Test-Ban Treaty requires, among other things, accurate modelling of the transport of radionuclides in the atmosphere. Crucial to atmospheric transport models (ATMs) when dealing with radioactive particulates are several removal processes, such as dry and wet deposition. Wet deposition in particular plays an often dominant role in the total...
Detection of radionuclides generated from underground nuclear explosions depends, first and foremost, on the movement of nuclides from source to detector. The subsurface environment therefore has a critical role in determining how and when material signatures become detectable. Field-scale tracer experiments are essential to furthering scientific understanding of how the subsurface contains...
A radiological emergency preparedness system in Korea has been developed to predict the behavior of radioactive material released into the environment and estimate the dose assessment for humans in case of a nuclear accident. The system is composed of atmospheric dispersion, marine dispersion, and dose assessment models, along with a graphic user interface module. It can evaluate the...
Given that the on-site inspection area should not exceed 1000 km2, finding the suspected nuclear explosion site is a difficult task requiring extremely accurate methods of assessment. One of the approaches used for nuclear explosion monitoring is to consider sources of radioxenon. Currently, mainly nuclear power plants and medical isotope production facilities are considered as a relevant and...
Of the existing nuclear reactors in the world, the region of the Group of Latin America and the Caribbean (GRULAC) currently has a total of six nuclear power plants operated by Argentina, Brazil and Mexico and 16 research reactors being operated by Argentina, Brazil, Chile, Colombia, Jamaica, Mexico and Peru. Using the RNToolkit web software that allows quick access to data from the...
Current noble gas detection systems for nuclear explosion monitoring are based on the detection of four radioxenon isotopes – Xenon-131m, -133, -133m and -135. The data provided by radioxenon detection could be enhanced by other radionuclide signatures, such as Argon-37. Activation of Calcium-40 in rock by neutrons produces Argon-37, and monitoring for this additional nuclide could help...
Argentina is one of the producers of radioisotopes and the construction of RA-10 responds to the increase in global demand. Increased production of radioisotopes could lead to more release of noble gases. This modern reactor is designed as a multipurpose facility suitable for radioisotope production, material and fuel irradiation research and neutron techniques applications. It is planned to...
Following an underground nuclear explosion, fission products may be vented to the surface and transported through the atmosphere. Traditional requirements for nuclear explosion monitoring systems have focused on simple release scenarios. A more rigorous evaluation of radionuclide inventory releases will provide better requirements for measurement systems and improve analysis of detections. The...
The International Monitoring System (IMS) detects background radioxenon from civilian sources every day. This measurement of the background can interfere with the measurements of radioxenon from nuclear tests. There are methods to discriminate civilian sources with nuclear tests. These include the use of atmospheric transport modelling to determine if the air associated with an IMS measurement...
Measuring radioxenon isotopes is one of the tools used for underground nuclear explosion monitoring. Medical isotope production and reactors also release radioxenon isotopes and discrimination of these benign sources is a key research area. Four isotope ratios have been shown to be a powerful method for discrimination if the isotopes are detected. This research has examined the expected...
Radioxenon is a gaseous fission product produced during nuclear weapons testing. Besides nuclear testing, the biggest radioxenon emission comes from medical isotope production facilities, which emit 109 -1013 Bq/day, while the power plant emits 109 Bq/reactor/day. However, the recent development of generation-IV reactors showed that a potential radioxenon release from a single molten salt...
The global atmospheric background of anthropogenic radionuclides hinders the ability of the Treaty monitoring community to identify possible signatures of a nuclear explosion. In particular, the atmospheric radioxenon background, produced and sustained by civil nuclear facilities such as isotope production facilities (IPFs) and nuclear power plants (NPPs), causes detections on the...
In 2017, the Government of Japan decided to make a voluntary contribution to further enhance the capabilities of the CTBTO verification regime. In that framework, two transportable noble gas systems were deployed in Horonobe and Mutsu, Japan. They respectively started operating in February 2018 and March 2018. Continued operation of the two systems is now financially supported by funding from...
INVAP´s STAX monitor was installed and is measuring at the Ezeiza Atomic Center (CAE-CNEA), Buenos Aires, Argentina since November 2021. Initially, the equipment underwent aliveness tests and calibration with gas like radioactive sources. The electronic set-up was adjusted, in order to optimize measurement performance, thus enabling to track high activity concentration emissions in a...
The International Monitoring System (IMS) noble gas network has proven to be highly reliable, with many years of routine measurements sent to the International Data Centre. With the deployment of noble gas systems, international experts began to routinely see a noble gas background. This background has continued throughout the years, and every single day, the IMS has a radioxenon measurement...
The SPALAX-NG was qualified in 2021 for deployment at International Monitoring System stations. The SPALAX-NG has been operated for several years by CEA/DAM. The SPALAX-NG is a major evolution compared to first generation SPALAX with detection limits of 0.2 mBq/m3 in eight hours for all the relevant radioisotope of xenon, high resolution beta-gamma detection, modularity. This presentation...
To categorize radionuclide data from the International Monitoring System of the Comprehensive Nuclear-Test-Ban Treaty, the French National Data Center has developed, and has been using in operation for several years, an automated simulation of the industrial background. For all IMS noble gas stations, it calculates every day the expected Xe-133 activity concentrations due to industrial...
Atmospheric transport modelling (ATM) supports the radionuclide verification technology by providing a link between radionuclide detections and the regions of their possible source. In the case of an anomalous detection registered by the International Monitoring System (IMS) particulate network classified as Level 5, CTBTO sends a request for support to Regional Specialized Meteorological...
Radiocesium (Cs-137) is one of the by-products of nuclear fission processes in nuclear reactors and nuclear weapons testing. The deposits of Cs-137 on the ground are resuspended into the atmosphere by different mechanisms like strong winds and forest fires. The major sources can be accidents from nuclear reactors, such as the Chernobyl power plant accident and Fukushima as well as historic...
BAPETEN (Nuclear Energy Regulatory Agency of Indonesia) is currently developing the Indonesian – Radiation Detector Monitoring System (I-RDMS) as an early warning tool to detect environmental radiation exposure increases on the territory of Indonesia. This system aims to check the availability of representative and reliable real-time online data on environmental radioactivity as a Nuclear...
In this study we have used open access data from NASA Earth Science data System and meteorological data from the data set of the International Monitoring System (IMS) stations to find out correlations with the observable detections of radionuclides at the RN43 station in Nouakchott. The data fusion between IMS data and open access data can be considered as a tool for National Data Centres to...
Radionuclides produced from underground nuclear explosions can slowly migrate through the subsurface and vent to the atmosphere, where they are transported to detectors downwind. Underground test sites located in remote areas surrounded by complex terrain features, can greatly affect the detectability of radionuclides once they reach the atmosphere. We describe efforts to validate a modeling...
The Xenon Environmental Nuclide Analysis at Hartlepool (XENAH) collaboration involves scientists from the U.K., U.S and Sweden who are performing measurements of routine emissions from Hartlepool Power Station with cooperation of the reactor operator, EDF Energy. Three diverse and complimentary radionuclide monitoring techniques are being deployed, aiming to characterize radionuclide emissions...
Radionuclide emissions from worldwide nuclear facilities are frequently observed by the CTBT noble gas network. These ever-present and highly variable emissions of the four radioxenon isotopes relevant for CTBT monitoring weaken the abilities of global monitoring of nuclear explosions. This multifaceted problem requires a substantive approach to determining the key steps for distinguishing for...
P-to-S receiver functions of 10 broad-band seismographs installed along the geologically complicated edge of the Ethiopian plateau and the active Main Ethiopian Rift were examined to image the crustal structure beneath the region. Receiver functions were determined using the time domain iterative deconvolution method to calculate the Moho depth and Vp/Vs of the crust. Results indicate that the...
iNSPIRE (iNtegrated Software Platform for Interactive Radionuclide rEview) is a software application that was developed by the CTBTO International Data Centre (IDC), based on modern Python/Qt framework. A first release, which covers beta-gamma coincidence-based detection systems in use at IMS stations, was deployed in IDC operations and delivered to National Data Centres (NDC) late 2020. The...
The Standard Event Lists SEL1, SEL2 and SEL3 are automatically produced one, four and six hours, respectively, after the waveforms arrive at the International Data Centre (IDC) from the International Monitoring System (IMS) stations. The IDC analysts then interactively review SEL3 to generate the Late Event Bulletin (LEB), based on which the Reviewed Event Bulletin (REB) is being formed....
The Earth is a dynamic planet with abundant vibrating processes. Besides the earthquakes, volcanos and other activities, there is a special type of source called a persistent localized microseismic source, with long period almost harmonic signals and fixed location. The 26s (0.038Hz) and 28s (0.036Hz) tremors in the Gulf of Guinea are two typical persistent localized microseismic sources in...
The purpose of this research is to check the performance of the RsttMndc (enhanced RSTT model for Mongolia) model as a regional velocity model and the obtained minimum 1D velocity model for the Hangay region as a local model to relocate the events occurred in the Hangay region, central part of western Mongolia using iLoc4.0 location software comparing with the relocation results with RSTT...
The International Monitoring System at the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty continuously monitors the globe for nuclear explosions through seismic, infrasound, hydroacoustic, and radionuclide measurements to detect signals from possible nuclear explosions. The most complete understanding of the sources of measured signals can be achieved by combining the...
Machine Learning for Travel Time emulation (MaLTTe) is a deep learning method and computer code for emulating seismic-phase travel times that are based on a three-dimensional (3-D) Earth model. Greater accuracy of travel time predictions using a 3-D Earth model are known to reduce the bias of event location estimates and improve the process of associating detections to events. However,...
At the SnT2023, the evolution and sustainment of the International Monitoring System (IMS) was discussed by a panel chaired by the current IMS Director Xyoli Perez Campos and its former Directors Gerardo Suarez, Frederico Guendel, and Seismic Section Chief Sergio Barrientos.
The panelists examined the trajectory of the IMS from inception to its current state, and projected potential future...
Discussion of panelists on following questions:
- What is the purpose of exercises in the development of OSI capabilities?
- Why we need to validate OSI capabilities in integrated manner?
- Is there another way to validate OSI capabilities?
On 20 December 2020 an earthquake shook Gaborone city and its outskirts. This earthquake was recorded by some stations of the Botswana Seismological Network and also some from the International Monitoring System. Vertical components seismograms from these stations were analysed using Geotool software from the Comprehensive Nuclear-Test-Ban Treaty Organization and the Regional Seismic Travel...
Having been nearly universally accepted, the Comprehensive Nuclear-Test-Ban Treaty has yet to enter into force. Before the CTBT can enter into force, however, 44 countries listed in Annex 2 of the Treaty must sign and ratify it. It is clear that the Treaty’s entry into force and implementation will be in the hands of the next generation of leaders. Given that the CTBTO Youth Group (CYG) is a...
The Bolivian Orocline is part of the Central Andes, where the high compressional crustal strains owns complex systems of geological faults that may be active and might produce destructive earthquakes, such as the Aiquile 1998. Generally, some foreshock and aftershock happens, however, those may have lower magnitudes that are difficult to detect. Nowadays, it is possible to detect any seismic...
The CTBT enjoys universal support in Africa. However, not all African states appreciate or utilise the benefits of closer cooperation with the CTBTO PrepCom to, for example, achieve the UN Sustainable Development Goals and the African Union's Agenda 2063. Hence, the paper intends to analyse and assess the status and utilisation of the CTBT in Africa. The aim is four-fold. The first aim is to...
Two seismic discontinuities delimit the mantle transition zone (MTZ) at 410 and 660 km. These seismic discontinuities were imaged under the north-west corner of South America using the receiver function technique and a seismological record of up to 30 years collected by the National Seismological Network of Colombia. Significant variations and spatially systematic in the discontinuity depths...
This article is dedicated to the issue of the Science Diplomacy Club (SDC) project. It is an emerging platform for young professionals in the field of scientific and technological cooperation. Nurturing a new generation of experts in the sphere of the CTBTO-related issues, such as non-proliferation, disarmament, and nuclear test ban remains a lynchpin of our activities.
The SDC policy is...
A network of 20 seismogeodetic instruments was installed in the subduction zone of Mexico. The purpose of the data is to monitor the crustal deformation of the subduction zone, to estimate the magnitude of great earthquakes, and to contribute to the tsunami warning system of Mexico operated by the Mexican Navy. Information generated by the network is transmitted in real time by dedicated...
The purpose of the National Data Centres for All initiative (NDCs4All) is to ensure equal distribution of Treaty benefits among States Signatories and to help them to receive International Monitoring System (IMS) data and International Data Centre (IDC) products.
When the PTS was formed after the Treaty opened for signature in September 1996, the media landscape was very different. Social media platforms like YouTube, TikTok, Snapchat, Instagram, LinkedIn, Facebook, and Twitter did not exist. Most people around the world got their news from a handful of media companies (cable news outlets MSNBC and Fox News in the United States and Al Jazeera in Qatar...
Source parameters and source time functions of the five contained Democratic People's Republic of Korea underground nuclear explosions, 2009-2017, are obtained from MDJ seismograms by Bayesian inversion. The test site is a few kilometres across. Therefore, the Earth impulse response, or Green’s function, from each event to a given distant seismometer, is essentially the same. The Green’s...
The National Data Centres (NDCs) are crucial for advising their National Authorities on nuclear explosion monitoring, and in many cases, they play an important role as station operators and in transmitting IMS data to the CTBTO in Vienna. This panel will discuss the synergy between the CTBTO and regional experts. The PTS provides technical assistance and training for building the required...
Sanctions are often imposed on countries with nuclear programs, such as Iran. The impact of the international sanctions and the United States’ sanctions on Iran, specifically since the deterioration of the Joint Comprehensive Plan of Action, has been extensive. The sanctions have crippled Iran’s economy and caused shortages in food, medication, and humanitarian aid. Accordingly, these...
Besides earthquakes, other sources can generate seismic and other observable geophysical signals that could potentially be misidentified or misinterpreted as explosions. One common source of such signals are collapses which, like explosions, are generally shallow and, consequently, have many identifying features similar to explosions. In this study, we collect, analyze and characterize...
CTBT's Article II, Subsection 8 provision could provide an interesting framework for leading different collaborative initiatives aimed at achieving nuclear weapon control, reduction or elimination goals. These goals should be settled in a new context in which new deployment of nuclear warhead in NATO members, the starting new nuclear race, the possibility of constructing undetectable computer...
The International Data Centre routinely applies event screening or discrimination in order to characterize events as either natural or anthropogenic. A number event discriminants are presented in literature. At the Kenya National Data Centre (KE-NDC), a systematic and step by step procedure of events discrimination are applied to seismic events. Results from the discriminants adopted are...
The paper attempts to understand India’s response to nuclear technology in the post-Fukushima period in the light of the debate concerning the safety, security and future of nuclear technology. Post-Fukushima period has generated a genuine, democratic and serious deliberation over nuclear technology which has called for public participation. As India has propounded multiple theories to justify...
ARISTOTLE-eENHSP (All Risk Integrated Trans-boundary Early-warning - enhanced European Natural Hazard Scientific Partnership) is a project financed by the European Civil Protection and Humanitarian Aid Operation (EC DG-ECHO) delivering real-time multi-hazard expert advice on worldwide natural disasters to the European Emergency Response Coordination Centre (ERCC).
ARISTOTLE-eENHSP was...
Rapid full source characterization provides useful information after the occurrence of an event of interest such as a nuclear test. Techniques using full moment tensor inversions based on long-period seismic waveforms recorded at regional distance helps to confirm the isotropic component of a seismic source, if any. Used on a grid of potential locations and by scanning continuous seismic...
Besides improved instrumentation and operational measurement analysis, radionuclide technology used at National Data Centres (NDCs) also benefits from atmospheric transport modeling (ATM) in their dedication to detect, discriminate and characterize nuclear explosions. A way to enhance NDC expertise is to provide ATM with a likely radionuclide source term emitted to the atmosphere following...
Designing an array is one of the main tasks during setup planning. Array configuration depends on the goal of monitoring, which may cover a large variety of purposes including monitoring of the desired area, local seismicity, global teleseismic monitoring, etc. In this study, we developed a method to automatically design an array configuration for regional monitoring purposes by optimizing the...
Focus on CYG as a tool for sustaining global action / interest on CTBT
26 years after its opening for signature in September 1996, the CTBT has garnered 186 signatures from countries in all parts of the world, 176 of whom have now ratified, making it one of the most widely accepted Treaties in the world today. The Treaty has thus not only demonstrated acceptability, it is with its efficient...
Infrasound station PVCI (50.53°N 14.57°E) from the Czech microbarograph network, C9 (https://doi.org/10.7914/SN/C9) is integrated in the Central and Eastern European Infrasound Network (CEEIN, www.ceein.eu). A correct evaluation of detections on the station level is essential for network data processing and localization and identification of events. To improve the knowledge of the infrasound...
The Provisional Technical Secretariat (PTS) defined a quality assurance programme for infrasound measurement systems of the International Monitoring System (IMS). This resulted in collaborations with international experts in the field of infrasound, metrology, and quality assurance. An objective is to ensure consistency in measurements and equivalence in data produced across the IMS network....
The development of laboratory calibration methods for seismometers and microbarometers in the low frequency range down to 0.01 Hz provides the possibility of a traceable on-site calibration during operation for field sensors of the International Monitoring System. The laboratory calibrated reference sensors can be installed as transfer standards at the stations co-located to the operational...
A thunderstorm is a well-known and permanent source of infrasound events. Infrasound signal propagation is known as well to be dictated by atmospheric parameters like temperature and wind. In a tropical region like Madagascar, rainfall pattern is one possible technique used to explain seasonal variation of International Monitoring System infrasound network detectability. In this study, 20...
The empowerment of the next generation of experts, capable of supporting the mission of the CTBTO, both politically and technically, and advancing the universalization and entry into force of the CTBT is a cross-cutting objective. This commitment is equally aligned with the UN system-wide effort of meaningful youth engagement, outlined in the UN Secretary-General’s “Youth 2030” strategy,...
The atmosphere is changing on a wide variety of timescales. The infrasound component of the International Monitoring System (IMS ) can sense such changes, each second over periods of tens of years. Such long term measurements of atmospheric variability enable the study of climate change. Infrasonic waves passively probe the entire atmosphere. The challenge is to unravel temperature variability...
Using robotic systems for scientific field data acquisition has expanded tremendously in the last five years and includes underground explosion monitoring and verification applications. Robotic platforms offer safer and more affordable ways to collect multiple data modalities, including visual and thermal infrared information, in challenging environments. An example of a new application space...
Understanding the impacts of near-field air flow on the long range transport of radionuclides in the atmosphere after a release from an underground nuclear explosion requires improved modeling at the local scale. In this work, we present the design of a radiotracer experiment in a complex terrain environment in support of modeling improvements. A remotely controlled release of Xe-127 gas,...
In environments where there is relatively little available open source information the analysis of satellite imagery data can be of particular value in monitoring for indications of nuclear weapon test preparation activities, such as signs at suspected nuclear weapon test locations of increased vehicle traffic, construction of support buildings, and tunnel excavations. This paper will use the...
A massive explosion in Tianjin occurred at a container port on August 12, 2015. The explosion produced a strong infrasound of extremely high signal to noise ratio registered by domestic infrasonic stations several kilometers away. Different from the ordinary explosion infrasound, Tianjin explosion infrasonic signals appear as six consecutive groups of clear first arrival. This reveals the...
The role of the CTBTO is to detect any atomic explosion on the planet. It also has the mission of convincing States to renounce nuclear testing. The implementation of a good communication strategy is a major challenge. For a communication strategy to be relevant, it must be based on a good analysis of the situation the objectives that can be set, the desired results and impact and the possible...
Seismic monitoring is one of the most common monitoring regimes used and the biggest network at CTBTO, with a total of 50 primary and 120 auxiliary stations. This is due to the more understandable nature of interaction between the seismic waves and the heterogeneous earth's subsurface. Data obtained from the primary and auxiliary seismic stations across the globe is automatically processed by...
Recent upgrades to the seismic network in Jamaica has significantly improved the country’s capacity for seismic monitoring and scientific research. The network now includes 13 broadband sensors, 12 short period seismometers and 42 strong motion accelerographs installed across the island. Devastating historical events including the infamous 1692 and 1907 earthquakes underscores the need for...
This presentation gives examples on how a National Data Centre (NDC) can automatically detect seismic events data obtained in near real time from the IMS through the SeedLink service available on the Global Communications Infrastructure (GCI), using the seismic analysis software NETDET that is part of the SEISAN package. We also show how to integrate the GCI data with locally collected data...
Since the different seismological stations of the CTBT have been successfully developed and installed around the world, a set of experiences has been accumulated that have been used to build a better management system, inside and outside the CTBT. This knowledge base has been used at the national level of each country, where personnel and operators are part of the scientific and seismological...
Since 2014, University of British Columbia professors Allen Sens and Matt Yedlin have taught the transdisciplinary course, “Nuclear Weapons and Arms Control” to a mixed cohort of engineering and political science undergraduates. A thousand students in total have experienced our flipped classroom model which integrates science and policy content, with a particular focus on the CTBTO. The course...
At face value, Indonesia seems promising for women interested in working in nuclear security, peace negotiations, and non-proliferation. Women make up about 40% of total employees in related governmental institutions and in academia. However, diplomacy, nuclear security, and non-proliferation are perceived as prominent "masculine" activities. In addition, the belief that each field is mutually...
In 1999, Jordan signed the Facility Agreement to establish and upgrade the seismic auxiliary monitoring station hosted in Jordan to implement the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Jordan signed the treaty on 26 September 1996 and ratified it on 25 August 1998. Since the Jordan National Data Centre (NDC) was established in 2004 and started receiving data from International...
Current international diplomacy cannot secure a state’s support of the CTBT without the internal citizen-based support of the Treaty. In most regime types, the citizen masses are often vital to influencing government decisions. For instance, in the late 1960s, anti-nuclear testing groups were instrumental in bringing the issue of nuclear disarmament to national elections. Alongside...
The Pelindaba Treaty which aims to create a nuclear weapon-free zone in Africa entered into force in July 2009. The African Commission on Nuclear Energy was created for the implementation of the treaty’s provisions and to develop nuclear sciences and techniques. In this context it also consists of political statements of many African countries aiming to embark on nuclear power programs and...
Nuclear testing has had devastating effects on cultures, histories, and populations worldwide. The disproportionate impacts on marginalized populations within nuclear armed states are largely excluded from mainstream narratives, which instead justify nuclear proliferation through propagandizing themes of scientific progress, military prowess, and political prestige.
The project aims to...
Capacity building is fundamental for strengthening the CTBT verification regime. The Commission is supporting the States Signatories in providing means to develop capabilities to actively participate in the CTBT verification regime. The donation and installation of IT equipment, the so-called Capacity Building System (CBS), at National Data Centres (NDC) of States Signatories is a significant...
Despite not signing the CTBT, Islamabad actively contributed to negotiations that led to the Treaty’s finalization at the Conference on Disarmament, and considers CTBT as the “primary mechanism for ending nuclear weapons testing.” However, outreach efforts face headwinds due to Islamabad’s heightened skepticism of India, its nuclear-armed neighbor, and what it sees as New Delhi’s limited...
Since 2002, when Bolivian International Monitoring System (IMS) stations (IS08, LPAZ, and SIV) began transmitting data, the Bolivian National Data Centre (NDC) has made an effort to effectively participate in the verification regime of the Treaty using IMS stations and NDC in a box programs for integrating data acquisition, processing and analysis. Thanks to the different trainings of CTBTO,...
Jordan's foreign policy continues to open up to the countries of the world and international organizations, interact with them, exchange experiences, and cooperate in various fields to develop the capabilities of the Jordanian state and provide the best services to Jordanians at home and around the world.
Jordan deposited its instrument of ratification of the Comprehensive Nuclear-Test-Ban...
After more than 20 years of its opening for signature, CTBT is facing ever-decreasing attention from the younger generation according to my observation while I have been teaching some related courses in my university, Bejing Language & Culture University, China, for more than ten years. Therefore, it’s very necessary to make more efforts to educate the young people to raise their awareness and...
The new National Data Center (NDC) Capacity Building Training cycle on the access and analysis of International Monitoring System (IMS) radionuclide data was launched in 2022 based on the collected feedback during the previous trainings and meetings. The Capacity Building and Training (CBT) Section with cooperation with software application took the initiative to design and draft the program...
We propose the creation of a pilot, scalable, university-accredited online course, with both asynchronous content and synchronous workshops, to better educate students worldwide on the CTBTO’s mandate and nuclear non-proliferation, repurposable in other contexts. The themes of the course would include the historical and political context of nuclear weapons and arms control, the technical...
In 2012, thanks to synchronous work between CTBTO and FACEN - UNA (Facultad de Ciencias Exactas y Naturales de la Universidad Nacional de Asunción), the National Data Center of Paraguay (NDCpy) was set up and inaugurated in the FACEN seismology laboratory. In this first stage, it had a server and a PC. Our two stations (CPUP and IS41) and the primary seismic CTBTO stations in South America are...
Individuals with disabilities remain significantly underrepresented in science, technology, engineering, and mathematics (STEM) fields. Recent data from the National Center for Education Statistics (NCES), reports that roughly 20% of all undergraduates within the United States report having one or more disabilities. Among the initial undergraduates that self-reported as having a disability,...
Ghana is steadily progressing towards the accomplishment of her Nuclear Power Program. The Nuclear Regulatory Authority was established by Act 895, 2015 to provide for the regulation and management of activities and practices for the peaceful use of nuclear material and provide for safety environmental protection and of persons against the harmful effects of radiation hazards. Ghana ratified...
Although the CTBTO has primary and auxiliary seismic stations in the International Monitoring System (IMS), it may be interesting to include local stations for the NDCs, but these stations must comply with the quality parameters imposed by the IMS. The stations of this proposal are those managed by the CNS-UASD network (PCDR, SMDR, MCDR and SODR) that belong to the Dominican Republic (DR) and...
The study aims to understand how the government and media are reshaping nuclear discourse in India. An attempt is made to recognize the shift of discourse from theory to praxis. The study tries to understand how the rise of nationalist populism enhances the nuclear dangers and sees how the very idea of responsible and non-responsible nuclear states distinction is flawed. It will try to look at...
Mali signed the Comprehensive Nuclear-Test-Ban Treaty on February 18, 1997 then ratified it on August 4, 1999. In 2005 and within the framework of the activities of the International Monitoring System (IMS), the CTBTO implemented a National Data Centre (NDC) at the Direction Nationale de la Géologie et des Mines (DNGM) of Mali with partners such as the Malian Radiation Protection Agency...
OVSICORI is the institute in charge of earthquake and volcanoes monitoring in Costa Rica. As with other countries in Central America we have limited economical resources. Due to important government investment on 2010 we chose Antelope by BRTT as our main monitoring computational system. Antelope worked great for us at the beginning but in the following years we found out that most of the...
The PS26 is the first internationally recognized seismic station in Niger. The field study for the site installation was conducted in November and December 2001.
The PS26 station is located southwest of Niamey, near the town of Torodi. This region is part of the West African craton, composed of sedimentary belts of Birimian green rocks and granitic terraces of the late Archean or Neoarchean...
Myanmar is situated in a tectonically complex area. However, up-to-date instrumentation and communication infrastructure limit earthquake monitoring and research activities. In 2008, two broadband stations financed by China's Earthquake Administration were installed. With government funding, we set up 3 broadband stations in 2010. The Myanmar National Seismic Network code MM underwent a...
With the first articles published in late October 2022, and more in press, Seismica is becoming a free and open venue for the seismological community to publish results from the entire spectrum of seismological research and applications. Our mission is to publish original, novel, peer-reviewed research in the fields of seismology, earthquakes, and related disciplines. Seismica is a...
Strategic communication is important to create public awareness in every country about the devastating impacts caused by the use of nuclear weapons to eliminate the presence of nuclear weapons across the globe. Every community, nation, and region has some historical backgrounds and indigenous traditions that must be kept in mind while designing and selecting the mediums for public outreach...
Under the financial support of the Norwegian Center NORSAR provided in 2020-2022 within the joint project, the Kazakhstan National Data Centre (KNDC) upgraded its hard- and software in support of the CTBTO tasks implementation. A new state of the art equipment was installed at the centre in Almaty. A fail-safe information system was created to ensure the following:
- acquisition and storage...
As part of nuclear non-proliferation and disarmament measure by the UN General Assembly, the Comprehensive Nuclear-Test-Ban Treaty (CTBT) was adopted to prohibit nuclear test explosions and any other nuclear explosions in all environments (in the atmosphere, oceans, and underground). Thus, ultimately to enhance international peace and security. The International Data Centre (IDC) offers...
While the spectre of nuclear war still haunts Europe in the light of the Russia-Ukraine conflict, the role of the CTBTO in this conflict is not clearly defined in the media in the Middle East and North Africa (MENA). This hypothesis is based on observations and content analyses where few articles are dedicated to CTBTO. In my paper, if accepted, I will present the image of the CTBTO: how it is...
Even though the CTBT has not entered into force yet due to the inability of the remaining Annex II States to ratify it, its contributions to global peace and security has been acknowledged as important, particularly in the significant reduction of global nuclear weapons tests. A key hindrance to the global efforts towards the entry into force of the treaty thereby pushing it close to...
To monitor compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT), a verication regime is designed to detect any nuclear explosions conducted anywhere –underground, under water or in the atmosphere. In this poster, we will focus on the Libyan contribution to the main component of the verification regime as the progress in the installation of the International Monitoring System (IMS)...
Solomon Islands is located on an active zone of seismic activities where Indo-Australian Plate subducts beneath the Pacific Plate at a rate of approximately 95mm/yr towards the north-west. Solomon Islands is a double chained of islands that lies between Papua New Guinea in the North West and Vanuatu in the south-east.
The purpose of this paper is to present the distribution of the potential...
After Entry into Force, the Conference of States Parties shall according to CTBT, Article II, paragraph 27 (f) consider and review scientific and technological developments that could affect the operation of this Treaty. According to the CTBT, Article IV, paragraph 11: “Each State Party undertakes to cooperate with the Organization and with other States Parties in the improvement of the...
Land based networks deficit the low-magnitude seismic events associated with magmatic and tectonic processes at mid-ocean ridges due to expeditious attenuation of seismic waves in the solid Earth. However, low frequency T waves generated by such events travel over very long distances in the sound fixing and ranging (SOFAR) channel with little attenuation and can be monitored by regional...
Currently, ocean acoustic models codes provide accurate predictions of sound propagation for various realistic scenarios. However, for long range propagation of signals generated by airgun arrays, some issues remain unsolved. Most implementations apply to isotropic sources but airgun arrays are strongly directional. When modelling their source level, this directionality must be correctly...
In addition to monitoring the oceans for signs of nuclear explosions, International Monitoring System (IMS) hydroacoustic data have been used for a broad range of civil and scientific applications, including the study of submarine earthquakes. This work analyses T wave signals recorded at CTBT-IMS hydrophone station HA3 (Juan Fernández Islands, South Pacific Ocean) triggered by Kermadec...
The CTBTO verification system exists within the broader context of international organizations, global policy making and international collaboration as well as public awareness and safety. The CTBT International Monitoring System has almost been completed and the readiness for On-site Inspection has been demonstrated. This panel explores what lessons learned can be transferred to other control...
