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...
