Regional P-Coda for Stable Estimates of Body Wave Magnitude: Application to Novaya Zemlya and Nevada Test Site Events

2008 ◽  
Author(s):  
Kevin Mayeda
Keyword(s):  
Body Wave ◽  
Test Site ◽  
Nevada Test Site ◽  
Novaya Zemlya ◽  
Body Wave Magnitude

Soil strain near a nuclear detonation

1970 ◽  
Vol 60 (6) ◽  
pp. 1999-2014
Author(s):  
C. W. Olsen
Keyword(s):  
Large Strain ◽  
Body Wave ◽  
Test Site ◽  
Large Strains ◽  
Transverse Strain ◽  
Nevada Test Site ◽  
Static Data ◽  
Soil Strain ◽  
Inelastic Region ◽  
Body Wave Magnitude

Abstract Radial and transverse strain seismometers using 6.1-m Invar rods were installed 457, 914, and 1524 m from ground zero on a nuclear detonation at the Nevada Test Site. The detonation, Hutch, took place in alluvium at a depth of 548 m and gave a body-wave magnitude of 5.4 ± 0.2. Dynamic and quasi-static strain data were recorded along with triaxial accelerations at the 914-m location. The dynamic data show large strains (2 × 10-3 and considerable shear-wave activity related to the subsurface structure. Decay with range, corrected for the inelastic region, shows dependence of peak amplitudes of about R-3, but influence of the alluvium is present. The quasi-static data show large strain steps (> 10-4) at the two nearer stations and considerable dependence on alluvium depth. The strain decay with time is not consistent with that observed on Benham, and, at 914 m, appears to be a permanent step, similar to that observed on the Jorum event.

Canadian detection and discrimination thresholds for earthquakes and underground explosions in Asia

1969 ◽  
Vol 6 (6) ◽  
pp. 1455-1458 ◽  
Author(s):  
P. W. Basham
Keyword(s):  
Surface Wave ◽  
Surface Waves ◽  
Central Asia ◽  
Body Wave ◽  
Test Site ◽  
Discrimination Threshold ◽  
Nevada Test Site ◽  
Novaya Zemlya ◽  
Seismograph Network

A suite of 33 Asian earthquakes and 36 Central Asia and Novaya Zemlya underground explosions are used to define the minimum detection levels in terms of surface-wave and body-wave magnitudes and the discrimination thresholds of the M versus m discriminant for the Canadian seismograph network. Under low microseismic noise conditions surface-waves can be observed for earthquakes down to m 4.9 and explosions down to m 5.9 for the region near the central Asia test sites. For events above these magnitudes, the M versus m relationships provide reliable discrimination between earthquakes and explosions. Comparison with an intracontinental study leads to the conclusion that the discrimination threshold is limited by path effects and greater distances to events about m 1.0 larger near the Asian test sites than near the Nevada test site.

P-wave spectra of nevada test site events at near and very near distances: Implications for a near-regional body wave-surface wave discriminant

1976 ◽  
Vol 66 (3) ◽  
pp. 803-825
Author(s):  
William A. Peppin
Keyword(s):  
Scaling Laws ◽  
Body Wave ◽  
Test Site ◽  
P Wave ◽  
Spectral Amplitude ◽  
Source Spectrum ◽  
Wave Spectra ◽  
Nevada Test Site ◽  
Field Source ◽  
Source Spectra

abstract Some 140 P-wave spectra of explosions, earthquakes, and explosion-induced aftershocks, all within the Nevada Test Site, have been computed from wide-band seismic data at close-in (< 30 km) and near-regional (200 to 300 km) distances. Observed near-regional corner frequencies indicate that source corner frequencies of explosions differ little from those of earthquakes of similar magnitude for 3 < ML < 5. Plots of 0.8 to 1.0 Hz Pg spectral amplitude versus 12-sec Rayleigh-wave amplitude show a linear trend with unit slope over three orders of magnitude for explosions; earthquakes fail to be distinguished from explosions on such a plot. These spectra also indicate similar source spectra for explosions in different media (tuff, alluvium, rhyolite) which corroborates Cherry et al. (1973). Close-in spectra of three large explosions indicate that: (1) source corner frequencies of explosions scale with yield in a way significantly different from previously published scaling laws; (2) explosion source spectra in tuff are flat from 0.2 to 1.0 Hz (no overshoot); (3) the far-field source spectrum decays at least as fast as frequency cubed. Taken together, these data indicate that the following factors are not responsible for Peppin and McEvilly's (1974) near-regional discriminant: (a) source dimension, (b) source rise time, or (c) shape of the source spectrum.

Lg magnitudes and yield estimates for underground Novaya Zemlya nuclear explosions

1988 ◽  
Vol 78 (2) ◽  
pp. 873-884
Author(s):  
Otto W. Nuttli
Keyword(s):  
Large Range ◽  
Test Site ◽  
Nevada Test Site ◽  
P Values ◽  
Underground Nuclear Explosions ◽  
Nuclear Explosions ◽  
Novaya Zemlya ◽  
Short Period ◽  
Lg Wave ◽  
Range Of Values

Abstract Lg-wave amplitudes of 30 Novaya Zemlya underground nuclear explosions, as recorded by short-period seismographs in Denmark, Finland, Germany, Norway, Spitsbergen, and Sweden, are used to determine mb(Lg) values. Assuming that the mb(Lg) versus explosion yield relation derived from Nevada Test Site data applies to all continental areas, the yields of the explosions are estimated. They cover a large range of values, from 2.5 to 4900 kt. The largest explosion since April 1976 had an estimated yield of 145 kt. The mb(Lg) values, when subtracted from the mb(P) values, can be used to estimate the mb(P) bias between two test sites. In this way, the mb(P) bias between Novaya Zemlya and the Nevada Test Site is estimated to be 0.20 magnitude units.

Monitoring nuclear test sites with GERESS

1996 ◽  
Vol 86 (1A) ◽  
pp. 172-190
Author(s):  
M. L. Jost ◽  
J. Schweitzer ◽  
H.-P. Harjes
Keyword(s):  
Test Site ◽  
Nevada Test Site ◽  
Data Set ◽  
Detection Thresholds ◽  
Novaya Zemlya ◽  
Tuamotu Archipelago ◽  
The Future ◽  
Nuclear Tests ◽  
Lop Nor ◽  
Eastern Kazakhstan

Abstract Since the installation of the 25-element GERman Experimental Seismic System (GERESS) array in southeastern Germany in 1990, 36 presumed nuclear tests were recorded by this system: 16 from Nevada, 12 from the Tuamotu Archipelago, 7 from Lop Nor, and 1 from Novaya Zemlya. Also, a chemical calibration experiment at Nevada Test Site (NPE) was observed at the array in 1993. In addition, two presumed nuclear events from Nevada, four from the Tuamotu Archipelago, and six from eastern Kazakhstan were recorded on temporary stations close to the GERESS array during the site survey (1988 to 1989). These latter 12 events were carefully included in this study to broaden the data set. This has been done since the number of underground nuclear tests observable at the GERESS site is not expected to increase significantly in the future because most nuclear powers have adhered to a moratorium on nuclear testing. In addition, we also do not expect that peaceful nuclear explosions (PNE) will be detonated in the future due to reasons of environmental hazard. Concentrating on Nevada Test Site and the Tuamotu Archipelago, a cross-correlation method and a cluster analysis indicate subgroups of the data. These empirical methods clearly discriminate presumed nuclear tests on the islands of Mururoa and Fangataufa. In addition, detection thresholds at GERESS were estimated based on bodywave magnitudes published by ISC: mb = 4.3 for the Nevada Test Site, mb = 3.9 for the Tuamotu Archipelago, mb = 4.6 for Lop Nor, mb = 4.3 for Novaya Zemlya, and mb = 4.4 for eastern Kazakhstan. Clearly, these path-specific detection thresholds deviate substantially from those derived from global amplitude-distance relations (i.e., Gutenberg-Richter). This indicates that a network of seismic stations used for global monitoring purposes may need careful calibration.

Seismic magnitudes of underground nuclear explosions

1973 ◽  
Vol 63 (1) ◽  
pp. 105-131 ◽  
Author(s):  
P. W. Basham ◽  
R. B. Horner
Keyword(s):  
Computational Procedure ◽  
Test Site ◽  
P Wave ◽  
Nevada Test Site ◽  
Underground Nuclear Explosions ◽  
Nuclear Explosions ◽  
Novaya Zemlya ◽  
Yield Information ◽  
Short Period ◽  
Propagation Effects

abstract Using an Ms computational procedure that minimizes path-propagation effects, and with Ms values found to be empirically independent of test site and detonation medium among consolidated rock explosions, available yield information is employed to illustrate that the seismic scaling of explosions in realistic detonation environments produces teleseismic Rayleigh-wave displacements proportional to the 1.2-power of yield over the range from low yields to greater than three megatons. Ms values independent of network, path, and site can be employed to estimate unknown yields at uncalibrated test sites to within average errors judged to be about 20 per cent. P-wave magnitudes, in the form of a calibrated teleseismic measure of short-period P-wave displacements, show a theoretically supported dependence of displacement on the 1.1-power of yield over the range from 6 kt to 1 mt. Studied explosions separate into two categories: the Nevada Test Site granite explosions, LONG SHOT, the Sahara February 1965 explosion and (by empirical inference) Novaya Zemlya and Eastern Kazakh explosions exhibit P-wave displacements about a factor of 3 greater than explosions of the same yield in tuff, rhyolite, and shale. P-wave magnitudes of explosions are subject to such a diversity of source, propagation, and measurement phenomena that any estimation of unknown yields without a closely controlled site and network calibration can be subject to large errors.

scholarly journals Seismological investigation of the 2016 January 6 North Korean underground nuclear test

2016 ◽  
Vol 206 (3) ◽  
pp. 1487-1491 ◽  
Author(s):  
Lian-Feng Zhao ◽  
Xiao-Bi Xie ◽  
Wei-Min Wang ◽  
Jin-Lai Hao ◽  
Zhen-Xing Yao
Keyword(s):  
Body Wave ◽  
Broad Band ◽  
Test Site ◽  
Nuclear Test ◽  
The Body ◽  
The North ◽  
Nuclear Tests ◽  
Master Event ◽  
Fully Coupled ◽  
Body Wave Magnitude

Abstract Seismology plays an important role in characterizing potential underground nuclear tests. Using broad-band digital seismic data from Northeast China, South Korea and Japan, we investigated the properties of the recent seismic event occurred in North Korea on 2016 January 6. Using a relative location method and choosing the previous 2006 explosion as the master event, the 2016 event was located within the North Korean nuclear test site, with its epicentre at latitude 41.3003°N and longitude 129.0678°E, approximately 900 m north and 500 m west of the previous event on 2013 February 12. Based on the error ellipse, the relocation uncertainty was approximately 70 m. Using the P/S spectral ratios, including Pg/Lg, Pn/Lg and Pn/Sn, as the discriminants, we identify the 2016 event as an explosion rather than an earthquake. The body-wave magnitude calculated from regional wave Lg is mb(Lg) equal to 4.7 ± 0.2. Adopting an empirical magnitude–yield relation, and assuming that the explosion is fully coupled and detonated at a normally scaled depth, we find that the seismic yield is about 4 kt, with the uncertainties allowing a range from 2 to 8 kt.

GIS surface effects map archive, Nevada Test Site, Nevada

2003 ◽  
Author(s):  
Dennis N. Grasso
Keyword(s):  
Surface Effects ◽  
Test Site ◽  
Nevada Test Site

Properties of Oak Spring formation in Area 12 at the Nevada Test Site

1959 ◽  
Author(s):  
W.H. Diment ◽  
R.E. Wilcox ◽  
G.V. Keller ◽  
E. Dobrovolny ◽  
F.C. Kracek ◽  
...  
Keyword(s):  
Test Site ◽  
Nevada Test Site
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