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Cooperative Seismology between Michigan State University in the USA, and Russia
Kevin Mackey1, Kazuya Fujita1, Larissa Gounbina2, and Sergei Shibaev3
1Michigan State University 2Magadan Affiliate - GS RAS, 3Yakutsk Affiliate – SB GS RAS
1. Abstract
Michigan State University in the USA and several seismic networks and institutions in Russia,
primarily in the east, have been cooperating in seismological research for over 20 years. Our
cooperative program has produced a large seismological database, and the most complete
seismicity map of eastern Russia. One main focus is the improvement of hypocenter
determinations and the acquisition of high quality ground truth (GT) data. We have recently
determined GT0 or GT1 locations for all PNEs that were conducted in Yakutia. For about half of
these PNEs, published coordinates were seismically determined, and we find that the locations
move about 7 km on average to the new GT0 or GT1 location. We are actively researching a new
set of GT determination criteria for use with the seismological data of eastern Russia. In this region,
most recorded seismological phases reported are secondary Pg and Sg (Lg onset) phases, which
are not compatible with the GT criteria established by Bondar et al. (2004). With the assistance of
mining companies in the Magadan region, we record blasting at both permanent and temporary
seismic stations, and analyze the data in the same manner as earthquakes, with particular attention
to secondary phase time picks. Subsequently, through statistical methods applied to varying
recorded phases and station distributions, we determine a set of rules for GT classification of
events.
4. Revised Source Parameters for PNEs in Yakutia3. Digitization of PNE Records
Figure 5. Hand digitized SP waveforms of PNEs originally recorded on photopaper.
7. Acknowledgments
We thank the Geophysical Survey, Russian Academy of Sciences and its affiliated branches, and the
Geophysical Survey, Siberian Branch, Russian Academy of Sciences and its affiliated branches for
making this project possible. Support for this work has been provided by the United States AFRL and DoE
contracts FA8718-08-C-0018 and DE-AC52-09NA29323 respectively.
2. Seismicity Database
Over several years, we have assembled the largest eastern Russia seismicity database
covering several seismic networks and containing over 275,000 distinct events, 2.1 million arrival
times and 1 million phase amplitudes. This database has been used to produce the first
comprehensive map of eastern Russia (Figure 1). We are now working to expand this database to
include the Altai-Sayan Network (Figure 2).
Figure 1. Seismicity map of eastern Russia.
Figure 2. Seismic networks of the former Soviet Union showing the coverage of our existing
seismicity database in blue (see Figure 1) and our planned expansion to include the Altai
Sayan network in red.
6. Extension of GT Criteria for Eastern RussiaWe are developing an improved set of GT determination criteria for Eastern Russia, which currently
do not typically lend themselves to the Bondár et al. (2004) criteria. The Bondár et al. (2004) criteria do
not accept Sg phases nor Pg phases available beyond the Pg/Pn crossover distance. Such Pg and Sg
phases comprise the bulk of our database and are of high quality. We have recently undertaken fieldwork
in eastern Russia to develop the new GT criteria for the region using mine blasts and temporary station
deployments. In April-May 2011 we deployed 9 temporary seismic stations in the Susuman mining region
of eastern Russia and recorded 6 explosions ranging up to 70 tons (Figure 11). The temporary sites
supplemented the regions permanent stations and were arranged to maximize statistical possibilities in
analysis. Data have not yet been analyzed. Similar fieldwork, but with a less than ideal station
distribution, was conducted in 2004, when it was generally found that that events could be located at the
GT-3 level using multiple phases and a locally calibrated travel-time curve, but with a poor distribution of
stations (Figure 12).
We are working to assemble, scan, digitize, and
analyze the historic Peaceful Nuclear Explosion (PNE)
seismograms from the regional networks of Russia.
Most seismograms are short period, and we have
collected and scanned approximately 350 thus far
(Figure 3). Figure 4 shows a screen capture of the
digitization process and Figure 5 shows examples of
completed 3-component digitizations. Although the
manual digitization of the short period seismograms is
labor intensive, we are able to recover the frequency
content from 1 Hz up to 5-8 Hz, depending on the
record (Figure 6).
Figure 4. Sample record showing the seismogram digitization process. This record depicts the
Z-component of the Neva 2-2 PNE as recorded at Yakutsk, 746 km distant.
Figure 3. PNE (circles) seismograms
collected and scanned (blue lines).
Figure 6. A) Hand digitized short period waveforms of a regional earthquake on 21 September
2008 recorded on photo paper at Yuzhno Sakhalinsk (YSS). B-D) Comparisons of frequency
spectra (left) and 1-5 Hz filtered waveforms (right) of the digitized data to GSN data from the co-
located IRIS station at YSS. Components are, top to bottom, Z, E-W, and N-S.
D
C
BA
N-S
Z
E-W
Table 1. Revised GT locations of Yakutian PNEs.
The use of satellite imagery combined with information being published in the open literature about
many of the PNE sites allows improvement or confirmation of the ground truth coordinates and derivative
velocity and origin time estimates. We are hoping to expand this study to PNEs in other regions of the
Former Soviet Union.
PNE02/13/2011
Proposed Coordinates Sultanov Coordinates Difference
(km)
Proposed GT
Latitude (ºN) Longitude (ºE) Latitude (ºN) Longitude (ºE)
Crystal (1974 10 02) 66.4573±.0001 112.3989±.0001 66.10 112.65 41.4 GT0
Neva 2-1 (1987 07 07) 61.4317±.0006 112.8860±.0012 61.50 112.85 7.8 GT0
Neva 2-2 (1987 07 25) 61.4172±.0011 112.8927±.0017 61.45 112.80 6.1 GT1
Neva 2-3 (1987 08 12) 61.4266±.0007 112.8879±.0012 61.45 112.80 5.4 GT0
Oka (1976 11 05) 61.4608±.0006 112.8592±.0010 61.458 112.860 0.3 GT1
Neva-1 (1982 10 10) 61.5006±.0006 112.9110±.0010 61.55 112.85 6.4 GT0
Vyatka (1978 10 08) 61.5565±.0008 112.9922±.0012 61.55 112.85 7.6 GT2
Sheksna (1979 10 07) 61.7679±.0001 113.1554±.0004 61.85 113.10 9.6 GT0
Craton-3 (1978 08 24) 65.9254±.0002 112.3330±.0002 65.925 112.338 0.2 GT0
Horizon-4 (1975 08 12) 70.7636±.0001 126.9518±.0001 70.763 126.953 0.1 GT1
Kimberlite-4 (1979 08 12) 61.7997±.0004 122.4161±.0007 61.803 122.430 0.8 GT0
Craton-4 (1978 08 24) 63.6800±.0002 125.5267±.0004 63.678 125.522 0.3 GT0
Recently, information on the detonation sites of the 12 PNEs conducted in the Sakha Republic (Yakutia)
in northeast Russia (hereafter, Yakutia) were published as parts of radionuclide contamination and
environmental studies (not all studies or information are cited here). These descriptions allow for the
improvement of the coordinates of these PNEs through the identification of disturbed areas, craters, and
containment features in satellite imagery. Accounting for uncertainties and alternative sites, all of them can
be located to within 0-2 km (GT0-GT2). Relative to the published coordinates of Sultanov et al. (1999), our
locations have a mean change of 6 km, with a maximum of 41km.
Figure 7. Index map of PNEs conducted in the Sakha
Republic (Yakutia). 1 – Crystal; 2 – Horizon-4, 3 – Oka, 4 –
Craton-4, 5 – Craton-3, 6 – Vyatka, 7 – Kimberlite-4, 8 –
Sheksna, 9 – Neva-1, 10 – Neva 2-1, 11 – Neva 2-2, and 12 –
Neva 2-3. Lines represent the three major DSS profiles: A –
Horizon, B – Kimberlite, and C – Craton. After Fujita (1995).
12 PNEs were detonated in the Yakutia between 1974 and
1987 (Figure 7), four as part of DSS profiles and the remainder
for oil recovery and mining purposes.
From 1978 to 2007, studies were conducted in the Sakha
Republic (Yakutia) to investigate possible radioactive
contamination around the PNE sites. Publications from these
studies yield much information about that is used to identify
likely detonation sites on satellite imagery. A few examples are
shown below.
Crystal was detonated to create a foundation for a tailings storage pond dam 2.5 km north of the
Udachnyi diamond mine. It produced a crater which was covered in 1992 with a “sarcophagus” (Figure 8a,
b). This site falls 41 km north-northwest from the location given by Sultanov et al. (1999).
Figure 8b. Detailed maps of the Crystal
site (Gedeonov et al., 1997) and
“sarcophagus” built to cover it in 1992.
Figure 8a. Google Earth image of the Udachnyi Mining
complex and encapsulated crater from the Crystal PNE
(dome). The small image shows a close-up of the site.
Figure 9. Location of PNEs in the Central Botuobuya Oil and
Gas field as published in a) Mikulenko et al. (2006; left) and
b) on satellite imagery (above). Locations of the PNEs as
given by Sultanov et al. (1999; yellow), and in this poster
(red) also shown. The town of Tas-Yuryakh shown as blue
dot.
A series of PNEs were detonated in the Tas-Yuryakh
region to enhance oil recovery and create storage in the
Central Botuobuya Oil and Gas field. The location of the
boreholes are given (e.g., Burtsev, 1993) in terms of
distances from the town of Tas-Yuryakh. However,
Mikulenko et al. (2006) presented a map showing the
details of the locations. Our proposed locations (Figure 9)
are based on areas of disturbed ground, often at the
confluence of roads, at localities constrained by the map
of Mikulenko et al. (2006).
5. Revised Source Parameters for the Mangyshlak
1 and 2 PNEs in KazakhstanIn 1969 and 1970, three PNEs were detonated in the Mangyshlak region of Kazakhstan. We have
identified what appear to be the collapse craters of the Mangyshlak 1 and 2 explosions (Figure 10).
Revised coordinates are shown in Table 2.
PNE6/6/2011
Proposed Coordinates Sultanov Coordinates Difference
(km)
Proposed GT
Latitude (ºN) Longitude (ºE) Latitude (ºN) Longitude (ºE)
Mangyshlak 1 (06-12-1969) 43.9099±.0002 54.7933±.0002 43.867 54.800 4.78 GT0
Mangyshlak 2 (12-12-1970) 43.8623±.0002 54.7727±.0002 43.85 54.80 2.59 GT0
Table 2. Revised GT locations of the Mangyshlak 1 and 2 PNEs.
Figure 10. Left – Locations of the Mangyshlak 1 and 2 PNE locations from Sultanov et al. (1999)
and this study. The new locations are identified by apparent collapse craters visible on Google Earth
Imagery. Right – The collapse crater from Mangyshlak 1 and associated topographic profiles.
Figure 11. Left – Locations of the temporary (pink) and permanent (red) seismic station deployments in
April-May 2011 to record GT mine explosions (yellow). Temporary stations were also deployed at the
mine sites. Right – Fieldwork and temporary station deployment photos.
Figure 12. Left – 2004 fieldwork temporary (small red) and permanent (large red) seismic station
deployments to record GT mine explosions (green). Center – Seismically determined locations of the
mine explosions. Each location was determined using only two of the temporary station sited, yet errors
do not exceed 3 km. Right - Sample seismograms from the mine explosions.