Novaya Zemlya Nuclear Test Base (NZNTB)

Keyword(s):  
1997 ◽  
Vol 87 (6) ◽  
pp. 1563-1575
Author(s):  
Frode Ringdal

Abstract A study of available seismic data shows that all but one of the 42 known underground nuclear explosions at Novaya Zemlya have been detected and located by stations in the global seismic network. During the past 30 years, only one seismic event in this area has been unambiguously classified as an earthquake (1 August 1986, mb = 4.3). Several other small events, most of which are thought to be either chemical explosions or aftereffects of nuclear explosions, have also been detected. Since 1990, a network of sensitive regional arrays has been installed in northern Europe in preparation for the global seismic monitoring network under a comprehensive nuclear test ban treaty (CTBT). This regional network has provided a detection capability for Novaya Zemlya that is shown to be close to mb = 2.5. Three low-magnitude events have been detected and located during this period, as discussed in this article: 31 December 1992 (mb = 2.7), 13 June 1995 (mb = 3.5), and 13 January 1996 (mb = 2.4). To classify the source types of these events has proved very difficult. Thus, even for the mb = 3.5 event in 1995, we have been unable to provide a confident classification of the source as either an earthquake or explosion using the available discriminants. A study of mb magnitude in different frequency bands shows, as expected, that the calculation of mb at regional distances needs to take into account source-scaling effects at high frequencies. Thus, when comparing a 4 to 8 or 8 to 16 Hz filter band to a “teleseismic” 2 to 4 Hz band, the smaller events have, relatively speaking, significantly more high-frequency energy (up to 0.5 mb units) than the larger events. This suggests that a P-wave spectral magnitude scale might be appropriate. The problem of accurately locating small events using a sparse array network is addressed using the 13 January 1996 event, which was detected by only two arrays, as an illustrative example. Our analysis demonstrates the importance of using accurately calibrated regional travel-time curves and, at the same time, illustrates how array processing can be used to identify an interfering phase from a local disturbance, thereby avoiding location errors due to erroneous phase readings.


Author(s):  
Trine Dahl-Jensen ◽  
Lif Lund Jacobsen ◽  
Ann-Sophie Graulund Sølund ◽  
Tine B. Larsen ◽  
Peter H. Voss

Abstract The paper seismograms from 100 years of observations in Denmark and Greenland has since October 2021 been made available through the Danish National Archives. Five case stories illustrate the quality and variation of the seismograms, and the historical context of operation of the stations. (1) The earliest recorded earthquake in the archive is recorded at GDH station in Greenland, where the 1907 Mw 7.2 earthquake in Tajikistan is recorded on smoked paper. (2) The first Danish earthquake is a local event close to Copenhagen in 1930. (3) We have illustrated the 50 megaton nuclear explosion in Novaya Zemlya in 1961—the largest nuclear test explosion ever. (4) The M 9.2 earthquake in Alaska in 1964 recorded on several instruments at COP. (5) A local earthquake in northeast Greenland recorded both on paper on World-Wide Standard Seismographic Network instruments and digitally on a modern broadband instrument.


2019 ◽  
Vol 1 ◽  
pp. 1-1
Author(s):  
Andrey Medvedev ◽  
Natalia Alekseenko ◽  
Maria Arsentyeva

<p><strong>Abstract.</strong> The Arctic region is currently at the next stage of increased interest not only from the Arctic States, but also from the entire world community. The main pollutants in the region are oil and gas products, heavy metals, chemical and radioactive contamination. The Arctic region of the Russian Federation has experienced a strong anthropogenic impact of radionuclides due to the use of nuclear energy. The main source of pollution is nuclear testing. About 132 tests were conducted on Novaya Zemlya, including 87 atmospheric, 3 underwater and 42 underground tests. Another source of radioactive contamination is the operation of the naval and civil nuclear fleet, as well as nuclear power plants (on the Kola Peninsula and in Bilibino). Until 1963, most of the tests were carried out in the atmosphere and under water, but after the signing of the Moscow Treaty on August 5, 1963, which prohibits the testing of nuclear weapons in three environments (under water, in the atmosphere and outer space), all tests were carried out underground, in tunnels and wells.</p><p>The object of research and mapping is the territory of the Novaya Zemlya archipelago and the nuclear test site located on it. On the territory of the nuclear test site constantly there was an assessment of the radioecological situation. The scientific community is interested in the processes taking place on the New Earth. The territory of the archipelago is constantly involved in various Arctic programs aimed at monitoring the level of environmental pollution and reducing the number of sources of pollution.</p><p>The aim of this work is to create multi-time animations of nuclear tests and the results of radionuclide pollution. These animated cartographic images differ not only in their time scales, but also a large set of qualitative and quantitative characteristics that characterize the results of anthropogenic influence.</p><p>As sources for creation of cartographic animations were: field data, remote sensing data (RS), Open sources, marine navigation maps, DEM’s (AsterDem, ArcticDem, GEBCO), meteorological data, thematic maps (including atlases), topographic maps, literary sources. The main part of the information about Novaya Zemlya archipelago was taken from the works of the Arctic marine complex expedition, which are devoted to the nature, history, archeology and culture of the archipelago. To obtain complete information about the explosions and their energy release ranges, additional open sources were used, from which it is possible to learn about the type of explosion, its power and location (geographical coordinates).</p><p>Dynamic geo-imagery was developed and established by the following method: study of object mapping and the collection of primary spatial data – creation script dynamic geo-imagery – the creation of a geodatabase of research – the creation of the thematic maps and layout of geo-imagery in the graphic editor – create animations with different time scales.</p><p>During the creation of cartographic animations based on the collected data, a multi-time multi-scale cartographic animation was developed, which allowed using the original graphical solution to visualize three interconnected time scales, which allowed to visualize the processes of infiltration and propagation of radioactive inert gases.</p>


1964 ◽  
Vol 42 (4) ◽  
pp. 632-637 ◽  
Author(s):  
Bhartendu ◽  
B. W. Currie

Photographic reproductions of the records of the A1 wave systems at Saskatoon (52.1 °N., 106.6 °W.) from five nuclear test explosions in Novaya Zemlya during the summer of 1962 are given. Notable differences exist between some of the records. These may be due to differences in the heights of the explosions. Dispersion curves of group velocity against period are shown. Waves ranged in period from 6.0 to 0.8 minutes; group velocities from 275 to 313 m/sec.


1999 ◽  
Vol 89 (4) ◽  
pp. 946-959 ◽  
Author(s):  
Tormod Kværna ◽  
Frode Ringdal

Abstract Continuous seismic threshold monitoring is a technique that has been developed over the past several years to assess the upper magnitude limit of possible seismic events that might have occurred in a geographical target area. The method provides continuous time monitoring at a given confidence level. In this article we expand upon previous work to apply the method to a global network of seismic stations and give examples of applications from a prototype system that will be installed at the International Data Center for monitoring the Comprehensive Nuclear Test Ban Treaty. Using a global grid of 2562 geographical aiming points, we computed site-specific threshold traces for each grid point and applied spatial interpolation to obtain full global coverage. For each grid point, the procedure is in principle to “focus” the network by tuning the frequency filters and array beams using available information on signal and noise characteristics at each station-site combination. Standard global P-phase attenuation relationships and travel-time tables (IASP91) are used in this initial implementation, but the system lends itself easily to applying station-site-specific corrections (magnitudes, travel times, etc.) to each seismic phase. We give examples of two main types of applications based on data from a worldwide seismic network: (a) an estimated continuous global threshold level and (b) an estimated continuous global detection capability. The first application provides a continuous view of the global seismic “background field” as calculated from the station data, with the purpose of assessing the upper magnitude limit of any seismic event that might have occurred anywhere on Earth. The second application introduces detection thresholds for each station and provides a simplified estimate, continuously in time, of the n-station detection capability of the network. The latter approach naturally produces higher threshold values, with the difference typically being 0.5-1 magnitude unit. We show that both these approaches are useful especially during large earthquakes, where conventional capability maps based on statistical noise and signal models cannot be applied. In order to illustrate the usefulness of combining global monitoring with site-specific monitoring for areas of special interest, we consider a large earthquake aftershock sequence in Kamchatka and its effect on the threshold trace in a very different region (the Novaya Zemlya nuclear test site). We demonstrate that the effects of the aftershock signals on the thresholds calculated for Novaya Zemlya are modest, partly because of the emphasis on high-frequency signals. This indicates that threshold monitoring could provide significantly improved seismic monitoring during aftershock sequences compared with conventional methods, for which the large number of detected phases tends to saturate the phase association process.


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