S i l i l I ti ti f th N ti l D t C t P d E i ... - CTBTO
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Si l i lI ti ti f th N ti lD t C t P d E i 2013 Seismological Investigation of the National Data Centre Preparedness Exercise 2013 Seismological Investigation of the National Data Centre Preparedness Exercise 2013 Seismological Investigation of the National Data Centre Preparedness Exercise 2013 Nicolai Gestermann Gernot Hartmann J Ole Ross and Lars Ceranna Nicolai Gestermann, Gernot Hartmann, J. Ole Ross , and Lars Ceranna BGR/B4 3 Federal Institute for Geosciences and Natural Resources Hannover Germany contact: nicolai gestermann@bgr de BGR/B4.3 - Federal Institute for Geosciences and Natural Resources, Hannover, Germany, contact: [email protected] Identification of Seismic Event Epicentre Location Accuracy Introduction Identification of Seismic Event Epicentre Location Accuracy Introduction Identification of Seismic Event Epicentre Location Accuracy Introduction The Comprehensive Nuclear Test Ban Treaty (CTBT) prohibits all kinds of nuclear The scenario of a hypothetical treaty violation can The Comprehensive Nuclear-Test-Ban Treaty (CTBT) prohibits all kinds of nuclear l i Th ifi ti i f th CTBT i d i d t dt t t t Different epicentre determinations were compared The scenario of a hypothetical treaty violation can explosion. The verification regime of the CTBT is designed to detect any treaty Different epicentre determinations were compared be verified or rejected with the investigation of All Stations violation While the data of the International Monitoring System (IMS) is collected Rf l ti with the reference location of KNMI A Jackknife be verified or rejected with the investigation of i i t hi h i d ti All Stations violation. While the data of the International Monitoring System (IMS) is collected, processed and technically analyzed at the International Data Centre (IDC) of the • Reference location f KNMI with the reference location of KNMI. A Jackknife Al ith d t ti t li ti i seismic events which occur in space and time processed and technically analyzed at the International Data Centre (IDC) of the CTBT O i ti N ti l Dt C t (NDC) f th b tt id from KNMI Algorithm was used to estimate a realistic epi- relation to the NPE2013 event Seven events in CTBT -Organization, National Data Centres (NDC) of the member states provide calculated with centre accuracy relation to the NPE2013 event. Seven events in interpretation and advice to their government concerning suspicious detections phases from 14 local centre accuracy . 2013 with a similar magnitude were selected for interpretation and advice to their government concerning suspicious detections. Th NDC P d E i (NPE) l l f d d li ith stations 2013 with a similar magnitude were selected for th t l l i All t h The NDC Preparedness Exercises (NPE) are regularly performed dealing with Rf unknown accuracy the spectral analysis. All events have a H t fictitious treaty violations to practice the combined analysis of CTBT verification Reference unknown accuracy I ti A f comparable amplitude decay of the power density Hyposat fictitious treaty violations to practice the combined analysis of CTBT verification technologies These exercises should help to evaluate the effectiveness of analysis from KNMI • Inspection Area of comparable amplitude decay of the power density German NDC technologies. These exercises should help to evaluate the effectiveness of analysis proced res applied at NDCs and the q alit completeness and sef lness of IDC 500 km 2 size would spectra which indicate that the NPE2013 event procedures applied at NDCs and the quality, completeness and usefulness of IDC Date 2013/09/04 be sufficient in case spectra which indicate that the NPE2013 event has the same so rce t pe as other si e ents of products. Origin time 01:33:32.13 01:33:32.81 of an OSI has the same source type as other six events of products. The exercise trigger of NPE2013 is a combination of a tempo spatial indication Origin time 01:33:32.13 01:33:32.81 Latitude 53 344°N 53 341°N Distances to Reference known induced origin in this region The exercise trigger of NPE2013 is a combination of a tempo-spatial indication i ti t ti f t d i ltd di lid t ti Latitude 53.344 N 53.341 N Longitude 6 772°E 6 752°E Distances to Reference Location 500 k 2 I ti A known induced origin in this region. pointing to a certain waveform event and simulated radionuclide concentrations Longitude 6.772 E 6.752 E D th 30k fi d 69k ± 22k Location 500 km 2 Inspection Area generated by forward Atmospheric Transport Modelling based on a fictitious release Depth 3.0 km fixed 6.9 km ± 2.2 km 4.1 km EMSC generated by forward Atmospheric Transport Modelling based on a fictitious release. For the waveform event the date (4 Sept 2013) is given and the region is Magnitude 2.8 M L 2.9 M L 2.2 km GER-NDC Standard For the waveform event the date (4 Sept. 2013) is given and the region is i td i h i th fi titi tt f "Fi i " t th C t f th L L Region Groningen (Netherland) 1.4 km GER-NDC Hyposat Seismic Station IBBN communicated in a map showing the fictitious state of "Frisia" at the Coast of the Seismic Station IBBN North Sea in Central Europe • Distance to epicenter North Sea in Central Europe. Th t ti l ti bt th f d di lid id i Jackknife Algorithm • Distance to epicenter ∆ = 135 km Only IMS Stations The potential connection between the waveform and radionuclide evidence remains Jackknife Algorithm • G t b t f ∆ = 135 km Only IMS Stations unclear for exercise participants. The verification task was to identify the waveform • Low location • Generate subsets of • Frequencies up to unclear for exercise participants. The verification task was to identify the waveform event and to investigate potential sources of the radionuclide findings The final Low location accuracy due to onset times 20 Hz event and to investigate potential sources of the radionuclide findings. The final ti h th th fi di CTBT l t d j tif t f O accuracy due to missing stations at • Calculate epicentres • Similar energy content question was whether the findings are CTBT relevant and justify a request for On- missing stations at local distances Calculate epicentres of each subset (blue) Similar energy content for wavetrain of P and S Frequency Site-Inspection in “Frisia”. In the following, the detection and investigation of the local distances of each subset (blue). Crosses correspond for wavetrain of P and S range for analysis Site Inspection in Frisia . In the following, the detection and investigation of the seimic event in Frisia“ is presented • Inspection Area of Crosses correspond to the accuracy of a • Spectrum analysis in analysis seimic event in „Frisia is presented. Inspection Area of 1000 km 2 size and 1000 km 2 Inspection Area to the accuracy of a single solution the frequency range 1000 km size and the error ellipse of 1000 km Inspection Area single solution 2 – 10 Hz the error ellipse of the calculated • Estimate distance Seismic events (yellow) which occurred in the the calculated location would fail between median Seismic events (yellow) which occurred in the 2013 i th i th i i Epicentre Determination location would fail th f location from year 2013 in the same region as the seismic ti t( d) Epicentre Determination the reference l ti (KNMI) Jackknife procedure trigger event (red). location (KNMI) Jackknife procedure and Reference and Reference location to 1 8 km Fi IMS i i t ti (bl d ) i th di t f 680 900 k Di t t location to 1.8 km Five IMS seismic stations (blue and green) in the distance range of 680-900 km Distance to Rf L ti Realistic epicentre P h S h showed signals of the NPE2013 seismic event Additional 40 seismic stations (red) Reference Location accuracy ≈ 2 km z] P - phases z] S - phases showed signals of the NPE2013 seismic event. Additional 40 seismic stations (red) 24 3 km IMS Amplitude decay of 2 /Hz 2 /Hz of national networks were used to calculate the epicentre with reliable accuracy . 24.3 km IMS power density ec) 2 ec) 2 The closest station was 117 km apart power density spectra at IBBN m/s m/s The closest station was 117 km apart. spectra at IBBN m [(nm S t bl m [(nm Hypothetical Treaty Violation Scenario rum • Spectra are comparable f ll i rum The local velocity model Hypothetical Treaty Violation Scenario pectr for all seven events in pectr The local velocity model ifi d ith S h y Sp the frequency range y Sp was specified with S phase nsity 2 – 10 Hz. nsity velocities adapted to the A hypothetical scenario Den • Red: NPE2013 event Den The NPE2013 seismic trigger event occurred in velocities adapted to the A hypothetical scenario Fii id hid d d l wer • Red: NPE2013 event G K id d wer The NPE2013 seismic trigger event occurred in the area of the Groningen natural gas field The V P /V S relation from the • Frisia tried to hide an underground nuclear Pow Green: Known induced t Pow the area of the Groningen natural gas field. The V P /V S relation from the W d ti di (l explosion within a series of intended triggered or events gas production is accompanied by induced Wadati diagram (layers explosion within a series of intended triggered or gas production is accompanied by induced i i it ith it d t 3 6 M Thi below Moho) to improve induced seismic events Frequency [Hz] Frequency [Hz] seismicity with magnitudes up to 3.6 M L . This below Moho) to improve induced seismic events. Frequency [Hz] Frequency [Hz] L seismicity could be used to hide an the epicentre accuracy. de NPE2013 • Seismic events could be induced by massive fluid seismicity could be used to hide an gitud NPE2013 seismic event Seismic events could be induced by massive fluid ij ti t ll i th i i it f th t t underground nuclear explosion as described in long injection at wells in the vicinity of the test area. underground nuclear explosion as described in th h th ti l i th i ht h d l • Induced seismicity in the time period before and the hypothetical scenario on the right-hand C l i • Induced seismicity in the time period before and side The NPE2013 radionuclide signature did Conclusion N mber of phases after a nuclear test would distract attention from side. The NPE2013 radionuclide signature did Conclusion Number of phases after a nuclear test would distract attention from th t t not support a nuclear explosion source but a • P g : 12 the test. not support a nuclear explosion source but a t Th l i h t f th • The NPE2013 seismic event was not included in the bulletins of the IDC The event g • P : 41 D illi ti iti thi li thi reactor . The non-explosive character of the • The NPE2013 seismic event was not included in the bulletins of the IDC. The event P n : 41 S 9 • Drilling activities are nothing unusual in this are event is also indicated by seismic discrimi- has been detected at two primary seismic station (GERES NOA) and at two auxiliary • S g : 9 event is also indicated by seismic discrimi- has been detected at two primary seismic station (GERES, NOA) and at two auxiliary i i t ti (HFS EKA) • S n : 30 nation analysis results. seismic stations (HFS, EKA). n A total of 92 Distance range: nation analysis results. latitude A total of 92 phases Distance range: 117 – 900 km • The available detections from the seismic IMS stations lead to a epicenter accuracy latitude phases 117 – 900 km The available detections from the seismic IMS stations lead to a epicenter accuracy f b t 24 k I f OSI th li it d 1000 2 i ti ld f il th of about 24 km. In case of an OSI the limited 1000 m 2 inspection area would fail the Simplified geological cross section of • The Groningen field is part of the true location Simplified geological cross section of G i t l fi ld O t Ti Southern Permian Basin true location. Groningen natural gas field Onset Times Wadati Diagram Southern Permian Basin (Rotliegend sandstone formation) • With fdt f l l t ti d dj td l it dl th i t Wadati Diagram (Rotliegend sandstone formation). • It i th l t t l fi ld i • With use of data from local stations and adjusted velocity models the epicenter • It is the largest natural gas field in E accuracy could be improved to less than 2 km Europe. accuracy could be improved to less than 2 km. • The field started gas production • Thi d t t th il l f dditi l ti lt hi l f P n and S n phases in 1963. Production formation • This demonstrates the crucial role of additional national technical means for in 1963. Production formation depth is ≈ 3000 m verification tasks depth is 3000 m. • Id d i i it t td verification tasks. • Induced seismicity started i 1986 S i i t d • C i f t l h t i ti id tifi d th NPE2013 t th k in 1986. Seismic events occurred • Comparison of spectral characteristics identified the NPE2013 event as earthquake with magnitudes up to 3.6 M L . induced by natural gas production • A spacial correlation is observed induced by natural gas production. V P /V S = 1.74 A spacial correlation is observed between national gas fields and • Th i f ibl t t i l ti t th l ti f th i i NPE2013 P S between national gas fields and seismicity • The scenario of a possible treaty violation at the location of the seismic NPE2013 M f D t d H k 2007 seismicity event could be disproved A potential OSI request is not supported by the analysis Map from Dost and Haak 2007 After NAM production plan 2007 event could be disproved. A potential OSI request is not supported by the analysis. After NAM production plan 2007
Transcript of S i l i l I ti ti f th N ti l D t C t P d E i ... - CTBTO
S i l i l I ti ti f th N ti l D t C t P d E i 2013Seismological Investigation of the National Data Centre Preparedness Exercise 2013Seismological Investigation of the National Data Centre Preparedness Exercise 2013Seismological Investigation of the National Data Centre Preparedness Exercise 2013g g pNicolai Gestermann Gernot Hartmann J Ole Ross and Lars CerannaNicolai Gestermann, Gernot Hartmann, J. Ole Ross , and Lars Ceranna, , ,
BGR/B4 3 Federal Institute for Geosciences and Natural Resources Hannover Germany contact: nicolai gestermann@bgr deBGR/B4.3 - Federal Institute for Geosciences and Natural Resources, Hannover, Germany, contact: [email protected] g @ g
Identification of Seismic EventEpicentre Location AccuracyIntroduction Identification of Seismic EventEpicentre Location AccuracyIntroduction Identification of Seismic EventEpicentre Location AccuracyIntroductionThe Comprehensive Nuclear Test Ban Treaty (CTBT) prohibits all kinds of nuclear The scenario of a hypothetical treaty violation canThe Comprehensive Nuclear-Test-Ban Treaty (CTBT) prohibits all kinds of nuclear
l i Th ifi ti i f th CTBT i d i d t d t t t t Different epicentre determinations were comparedThe scenario of a hypothetical treaty violation can
explosion. The verification regime of the CTBT is designed to detect any treaty Different epicentre determinations were compared be verified or rejected with the investigation ofAll Stationsp g g y yviolation While the data of the International Monitoring System (IMS) is collected R f l tiwith the reference location of KNMI A Jackknife
be verified or rejected with the investigation ofi i t hi h i d ti
All Stationsviolation. While the data of the International Monitoring System (IMS) is collected,processed and technically analyzed at the International Data Centre (IDC) of the
• Reference location f KNMI
with the reference location of KNMI. A JackknifeAl ith d t ti t li ti i
seismic events which occur in space and timeprocessed and technically analyzed at the International Data Centre (IDC) of theCTBT O i ti N ti l D t C t (NDC) f th b t t id
from KNMIAlgorithm was used to estimate a realistic epi-p
relation to the NPE2013 event Seven events inCTBT-Organization, National Data Centres (NDC) of the member states provide calculated with g p
centre accuracyrelation to the NPE2013 event. Seven events ing , ( ) p
interpretation and advice to their government concerning suspicious detections phases from 14 localcentre accuracy. 2013 with a similar magnitude were selected forinterpretation and advice to their government concerning suspicious detections.Th NDC P d E i (NPE) l l f d d li ith
pstations
2013 with a similar magnitude were selected forth t l l i All t hThe NDC Preparedness Exercises (NPE) are regularly performed dealing with
R f unknown accuracy the spectral analysis. All events have aH t
p ( ) g y p gfictitious treaty violations to practice the combined analysis of CTBT verification Reference unknown accuracy
I ti A f
p ycomparable amplitude decay of the power densityHyposatfictitious treaty violations to practice the combined analysis of CTBT verification
technologies These exercises should help to evaluate the effectiveness of analysis from KNMI • Inspection Area of comparable amplitude decay of the power densityGerman NDCtechnologies. These exercises should help to evaluate the effectiveness of analysisproced res applied at NDCs and the q alit completeness and sef lness of IDC
500 km2 size would spectra which indicate that the NPE2013 eventprocedures applied at NDCs and the quality, completeness and usefulness of IDC Date 2013/09/04 be sufficient in case spectra which indicate that the NPE2013 eventhas the same so rce t pe as other si e ents ofproducts. Origin time 01:33:32.13 01:33:32.81 of an OSI has the same source type as other six events ofproducts.
The exercise trigger of NPE2013 is a combination of a tempo spatial indicationOrigin time 01:33:32.13 01:33:32.81Latitude 53 344°N 53 341°N Distances to Reference
yknown induced origin in this regionThe exercise trigger of NPE2013 is a combination of a tempo-spatial indication
i ti t t i f t d i l t d di lid t tiLatitude 53.344 N 53.341 NLongitude 6 772°E 6 752°E
Distances to Reference Location500 k 2 I ti A
known induced origin in this region.pointing to a certain waveform event and simulated radionuclide concentrations Longitude 6.772 E 6.752 E
D th 3 0 k fi d 6 9 k ± 2 2 kLocation500 km2 Inspection Areap g
generated by forward Atmospheric Transport Modelling based on a fictitious release Depth 3.0 km fixed 6.9 km ± 2.2 km 4.1 km EMSCgenerated by forward Atmospheric Transport Modelling based on a fictitious release.For the waveform event the date (4 Sept 2013) is given and the region is Magnitude 2.8 ML 2.9 ML 2.2 km GER-NDC StandardFor the waveform event the date (4 Sept. 2013) is given and the region is
i t d i h i th fi titi t t f "F i i " t th C t f thg L L
Region Groningen (Netherland) 1.4 km GER-NDC Hyposat Seismic Station IBBNcommunicated in a map showing the fictitious state of "Frisia" at the Coast of the Region Groningen (Netherland) Seismic Station IBBNp gNorth Sea in Central Europe • Distance to epicenterNorth Sea in Central Europe.Th t ti l ti b t th f d di lid id i Jackknife Algorithm
• Distance to epicenter∆ = 135 kmOnly IMS StationsThe potential connection between the waveform and radionuclide evidence remains Jackknife Algorithm
• G t b t f∆ = 135 km Only IMS Stationsp
unclear for exercise participants. The verification task was to identify the waveform • Low location• Generate subsets of • Frequencies up to unclear for exercise participants. The verification task was to identify the waveformevent and to investigate potential sources of the radionuclide findings The final
Low location accuracy due toonset times 20 Hzevent and to investigate potential sources of the radionuclide findings. The final
ti h th th fi di CTBT l t d j tif t f Oaccuracy due to missing stations at• Calculate epicentres • Similar energy contentquestion was whether the findings are CTBT relevant and justify a request for On- missing stations at local distances
Calculate epicentresof each subset (blue)
Similar energy content for wavetrain of P and SFrequency q g j y q
Site-Inspection in “Frisia”. In the following, the detection and investigation of the local distancesof each subset (blue). Crosses correspond
for wavetrain of P and Srange foranalysisSite Inspection in Frisia . In the following, the detection and investigation of the
seimic event in Frisia“ is presented • Inspection Area ofCrosses correspond to the accuracy of a
• Spectrum analysis in analysisseimic event in „Frisia is presented. Inspection Area of
1000 km2 size and1000 km2 Inspection Areato the accuracy of a single solution
the frequency range 1000 km size and the error ellipse of
1000 km Inspection Areasingle solution 2 – 10 Hzthe error ellipse of the calculated• Estimate distance
Seismic events (yellow) which occurred in thethe calculated location would failbetween median Seismic events (yellow) which occurred in the
2013 i th i th i iEpicentre Determination location would fail th flocation from year 2013 in the same region as the seismic
t i t ( d)Epicentre Determination the reference l ti (KNMI)Jackknife procedure trigger event (red).plocation (KNMI)Jackknife procedure
and Referenceand Reference location to 1 8 kmFi IMS i i t ti (bl d ) i th di t f 680 900 k Di t tlocation to 1.8 kmFive IMS seismic stations (blue and green) in the distance range of 680-900 km Distance to
R f L tiRealistic epicentreP hS h
( g ) gshowed signals of the NPE2013 seismic event Additional 40 seismic stations (red) Reference Locationp
accuracy ≈ 2 km z]
P - phases
z]
S - phasesshowed signals of the NPE2013 seismic event. Additional 40 seismic stations (red)24 3 km IMS Amplitude decay ofy
2 /Hz
2 /Hzof national networks were used to calculate the epicentre with reliable accuracy. 24.3 km IMS p y
power density
ec)2
ec)2o at o a et o s e e used to ca cu ate t e ep ce t e t e ab e accu acy
The closest station was 117 km apartpower density spectra at IBBN
m/s
m/sThe closest station was 117 km apart. spectra at IBBN
m [(
nm
S t blm [(
nm
Hypothetical Treaty Violation Scenario rum • Spectra are comparable
f ll irumThe local velocity model Hypothetical Treaty Violation Scenario pe
ctr for all seven events in
pect
rThe local velocity model ifi d ith S h ypot et ca eaty o at o Sce a o
y S
p the frequency range
y S
pwas specified with S phase
nsity 2 – 10 Hz.nsity
p pvelocities adapted to the A hypothetical scenario D
en
• Red: NPE2013 eventDenThe NPE2013 seismic trigger event occurred invelocities adapted to the A hypothetical scenario
F i i i d hid d d l wer
• Red: NPE2013 event G K i d dw
er The NPE2013 seismic trigger event occurred in
the area of the Groningen natural gas field TheVP/VS relation from the • Frisia tried to hide an underground nuclear Pow Green: Known induced
t
Powthe area of the Groningen natural gas field. TheVP/VS relation from the
W d ti di (l gexplosion within a series of intended triggered or
eventsgas production is accompanied by inducedWadati diagram (layers explosion within a series of intended triggered or gas production is accompanied by inducedi i it ith it d t 3 6 M Thi
g ( ybelow Moho) to improve induced seismic events Frequency [Hz]Frequency [Hz]seismicity with magnitudes up to 3.6 ML. Thisbelow Moho) to improve induced seismic events. Frequency [Hz]Frequency [Hz]y g p L
seismicity could be used to hide anthe epicentre accuracy.
de NPE2013 • Seismic events could be induced by massive fluidseismicity could be used to hide ant e ep ce t e accu acy
gitu
d NPE2013 seismic event
Seismic events could be induced by massive fluid i j ti t ll i th i i it f th t tunderground nuclear explosion as described in
long injection at wells in the vicinity of the test area.underground nuclear explosion as described in
th h th ti l i th i ht h dl j y• Induced seismicity in the time period before andthe hypothetical scenario on the right-hand
C l i• Induced seismicity in the time period before and yp g
side The NPE2013 radionuclide signature did ConclusionN mber of phases after a nuclear test would distract attention fromside. The NPE2013 radionuclide signature did ConclusionNumber of phases after a nuclear test would distract attention from th t tnot support a nuclear explosion source but a• Pg: 12 the test.not support a nuclear explosion source but a
t Th l i h t f th • The NPE2013 seismic event was not included in the bulletins of the IDC The eventg
• P : 41 D illi ti iti thi l i thireactor. The non-explosive character of the • The NPE2013 seismic event was not included in the bulletins of the IDC. The event Pn: 41
S 9• Drilling activities are nothing unusual in this are
pevent is also indicated by seismic discrimi- has been detected at two primary seismic station (GERES NOA) and at two auxiliary• Sg: 9
g gevent is also indicated by seismic discrimi- has been detected at two primary seismic station (GERES, NOA) and at two auxiliary i i t ti (HFS EKA)
• Sn: 30 nation analysis results. seismic stations (HFS, EKA).n
A total of 92 Distance range:nation analysis results. ( , )
latitudeA total of 92 phases
Distance range:117 – 900 km • The available detections from the seismic IMS stations lead to a epicenter accuracylatitude phases 117 – 900 km The available detections from the seismic IMS stations lead to a epicenter accuracy
f b t 24 k I f OSI th li it d 1000 2 i ti ld f il thof about 24 km. In case of an OSI the limited 1000 m2 inspection area would fail the Simplified geological cross section of• The Groningen field is part of the ptrue location
Simplified geological cross section of G i t l fi ldO t Ti
g pSouthern Permian Basin true location.Groningen natural gas fieldOnset Times Wadati DiagramSouthern Permian Basin (Rotliegend sandstone formation)
• With f d t f l l t ti d dj t d l it d l th i tWadati Diagram (Rotliegend sandstone formation).
• It i th l t t l fi ld i • With use of data from local stations and adjusted velocity models the epicenter • It is the largest natural gas field in E
j y paccuracy could be improved to less than 2 km
Europe.accuracy could be improved to less than 2 km. • The field started gas production
• Thi d t t th i l l f dditi l ti l t h i l fPn and Sn phases
g pin 1963. Production formation • This demonstrates the crucial role of additional national technical means for in 1963. Production formation depth is ≈ 3000 m
verification tasksdepth is 3000 m.
• I d d i i it t t d verification tasks.• Induced seismicity started i 1986 S i i t d • C i f t l h t i ti id tifi d th NPE2013 t th kin 1986. Seismic events occurred • Comparison of spectral characteristics identified the NPE2013 event as earthquake with magnitudes up to 3.6 ML . p p q
induced by natural gas production• A spacial correlation is observed induced by natural gas production.VP/VS = 1.74A spacial correlation is observed between national gas fields and
• Th i f ibl t t i l ti t th l ti f th i i NPE2013P S between national gas fields and
seismicity • The scenario of a possible treaty violation at the location of the seismic NPE2013 M f D t d H k 2007
seismicity p yevent could be disproved A potential OSI request is not supported by the analysis
Map from Dost and Haak 2007After NAM production plan 2007 event could be disproved. A potential OSI request is not supported by the analysis.After NAM production plan 2007
