際際滷shows by User: IvanKitov / http://www.slideshare.net/images/logo.gif 際際滷shows by User: IvanKitov / Tue, 09 Jan 2018 10:34:23 GMT 際際滷Share feed for 際際滷shows by User: IvanKitov Assessing the consistency, quality, and completeness of the Reviewed Event Bulletin with waveform cross correlation /slideshow/assessing-the-consistency-quality-and-completeness-of-the-reviewed-event-bulletin-with-waveform-cross-correlation/85906335 spotcheck-180109103423
The Reviewed Event Bulletin (REB) of the IDC includes more than 500,000 events with associated seismic phases. The quality of these events and its completeness depends on multistage automatic processing followed by interactive analysis. The IDC raw data archive allows to apply the method of waveform cross correlation (WCC) for assessment of the similarity between seismic signals associated with REB events, and thus, the overall bulletin consistency. For cross correlation, we create a global set of master-events (ME) in the areas where reliable seismic events are available in the REB. Using only events within 3 degrees from a given ME, we apply the Principal Component Analysis to signals at each associated station. The major components are used to build synthetic MEs. Using real and synthetic MEs, we process continuous data in a specified region with the aim to find new REB-compatible events, which are missing from the REB. Therefore, the developed method allows to test REB consistency, quality, and completeness in any specified region or globally. It can also be thought as an alternative to the manual spot check during an independent review of the REB in routine IDC event analysis or as an additional tool for the independent reviewer. ]]>
The Reviewed Event Bulletin (REB) of the IDC includes more than 500,000 events with associated seismic phases. The quality of these events and its completeness depends on multistage automatic processing followed by interactive analysis. The IDC raw data archive allows to apply the method of waveform cross correlation (WCC) for assessment of the similarity between seismic signals associated with REB events, and thus, the overall bulletin consistency. For cross correlation, we create a global set of master-events (ME) in the areas where reliable seismic events are available in the REB. Using only events within 3 degrees from a given ME, we apply the Principal Component Analysis to signals at each associated station. The major components are used to build synthetic MEs. Using real and synthetic MEs, we process continuous data in a specified region with the aim to find new REB-compatible events, which are missing from the REB. Therefore, the developed method allows to test REB consistency, quality, and completeness in any specified region or globally. It can also be thought as an alternative to the manual spot check during an independent review of the REB in routine IDC event analysis or as an additional tool for the independent reviewer. ]]> Tue, 09 Jan 2018 10:34:23 GMT /slideshow/assessing-the-consistency-quality-and-completeness-of-the-reviewed-event-bulletin-with-waveform-cross-correlation/85906335 IvanKitov@slideshare.net(IvanKitov) Assessing the consistency, quality, and completeness of the Reviewed Event Bulletin with waveform cross correlation IvanKitov The Reviewed Event Bulletin (REB) of the IDC includes more than 500,000 events with associated seismic phases. The quality of these events and its completeness depends on multistage automatic processing followed by interactive analysis. The IDC raw data archive allows to apply the method of waveform cross correlation (WCC) for assessment of the similarity between seismic signals associated with REB events, and thus, the overall bulletin consistency. For cross correlation, we create a global set of master-events (ME) in the areas where reliable seismic events are available in the REB. Using only events within 3 degrees from a given ME, we apply the Principal Component Analysis to signals at each associated station. The major components are used to build synthetic MEs. Using real and synthetic MEs, we process continuous data in a specified region with the aim to find new REB-compatible events, which are missing from the REB. Therefore, the developed method allows to test REB consistency, quality, and completeness in any specified region or globally. It can also be thought as an alternative to the manual spot check during an independent review of the REB in routine IDC event analysis or as an additional tool for the independent reviewer. <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/spotcheck-180109103423-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> The Reviewed Event Bulletin (REB) of the IDC includes more than 500,000 events with associated seismic phases. The quality of these events and its completeness depends on multistage automatic processing followed by interactive analysis. The IDC raw data archive allows to apply the method of waveform cross correlation (WCC) for assessment of the similarity between seismic signals associated with REB events, and thus, the overall bulletin consistency. For cross correlation, we create a global set of master-events (ME) in the areas where reliable seismic events are available in the REB. Using only events within 3 degrees from a given ME, we apply the Principal Component Analysis to signals at each associated station. The major components are used to build synthetic MEs. Using real and synthetic MEs, we process continuous data in a specified region with the aim to find new REB-compatible events, which are missing from the REB. Therefore, the developed method allows to test REB consistency, quality, and completeness in any specified region or globally. It can also be thought as an alternative to the manual spot check during an independent review of the REB in routine IDC event analysis or as an additional tool for the independent reviewer.
Assessing the consistency, quality, and completeness of the Reviewed Event Bulletin with waveform cross correlation from Ivan Kitov
]]> 89 3 https://cdn.slidesharecdn.com/ss_thumbnails/spotcheck-180109103423-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 Detection and location of small aftershocks using waveform cross correlation /IvanKitov/detection-and-location-of-small-aftershocks-using-waveform-cross-correlation mariupol-180109103054
Aftershock sequences of earthquakes with magnitudes 5.0 and lower are difficult to detect and locate by sparse regional networks. Signals from aftershocks with magnitudes 2 to 3 are usually below detection thresholds of standard 3-C seismic stations at near regional distances. For seismic events close in space, the method waveform cross correlation (WCC) allows to reduce detection threshold by at least a unit of magnitude and to improve location precision to a few kilometres. Therefore, the WCC method is directly applicable to weak aftershock sequences. Here, we recover seismic activity after the earthquake near the town of Mariupol (Ukraine) occurred on August 7, 2016. The main shock was detected by many stations of the International monitoring system (IMS), including the closest primary IMS array stations AKASG (6.62 deg.) and BRTR (7.81), as well as 3-C station KBZ (5.00). The International data centre located this event (47.0013N, 37.5427E), estimated its origin time (08:15:4.1 UTC), magnitude (mb=4.5), and depth (6.8 km). This event was also detected by two array stations of the Institute for Dynamics of Geospheres (IDG) of the Russian Academy of Sciences (RAS): portable 3-C array RDON (3.28), which is the closest station, and MHVAR (7.96). Using signals from the main shock at five stations as waveform templates, we calculated continuous traces of cross correlation coefficient (CC) from the 7th to the 11th of August. We found that the best templates should include all regional phases, and thus, have the length from 80 s to 180 s. For detection, we used standard STA/LTA method with threshold depending on station. The accuracy of onset time estimation by the STA/LTA detector based on CC-traces is close to one sample, which varies from 0.05 s at BRTR to 0.005 s for RDON and MHVAR. Arrival times of all detected signals were reduced to origin times using the observed travel times from the main shock. Clusters of origin times are considered as event hypotheses in the phase association procedure. As a result, we found 12 aftershocks with magnitudes between 1.5 and 3.5. These small events were detected neither by the IDC nor by the near regional network of the Geophysical Survey of RAS, which has three closest 3-C stations at distances of 2.2 to 3.5 degrees from the studied earthquake. We also applied procedure of relative location and all aftershocks were found within a few km from the main shock. ]]>
Aftershock sequences of earthquakes with magnitudes 5.0 and lower are difficult to detect and locate by sparse regional networks. Signals from aftershocks with magnitudes 2 to 3 are usually below detection thresholds of standard 3-C seismic stations at near regional distances. For seismic events close in space, the method waveform cross correlation (WCC) allows to reduce detection threshold by at least a unit of magnitude and to improve location precision to a few kilometres. Therefore, the WCC method is directly applicable to weak aftershock sequences. Here, we recover seismic activity after the earthquake near the town of Mariupol (Ukraine) occurred on August 7, 2016. The main shock was detected by many stations of the International monitoring system (IMS), including the closest primary IMS array stations AKASG (6.62 deg.) and BRTR (7.81), as well as 3-C station KBZ (5.00). The International data centre located this event (47.0013N, 37.5427E), estimated its origin time (08:15:4.1 UTC), magnitude (mb=4.5), and depth (6.8 km). This event was also detected by two array stations of the Institute for Dynamics of Geospheres (IDG) of the Russian Academy of Sciences (RAS): portable 3-C array RDON (3.28), which is the closest station, and MHVAR (7.96). Using signals from the main shock at five stations as waveform templates, we calculated continuous traces of cross correlation coefficient (CC) from the 7th to the 11th of August. We found that the best templates should include all regional phases, and thus, have the length from 80 s to 180 s. For detection, we used standard STA/LTA method with threshold depending on station. The accuracy of onset time estimation by the STA/LTA detector based on CC-traces is close to one sample, which varies from 0.05 s at BRTR to 0.005 s for RDON and MHVAR. Arrival times of all detected signals were reduced to origin times using the observed travel times from the main shock. Clusters of origin times are considered as event hypotheses in the phase association procedure. As a result, we found 12 aftershocks with magnitudes between 1.5 and 3.5. These small events were detected neither by the IDC nor by the near regional network of the Geophysical Survey of RAS, which has three closest 3-C stations at distances of 2.2 to 3.5 degrees from the studied earthquake. We also applied procedure of relative location and all aftershocks were found within a few km from the main shock. ]]> Tue, 09 Jan 2018 10:30:54 GMT /IvanKitov/detection-and-location-of-small-aftershocks-using-waveform-cross-correlation IvanKitov@slideshare.net(IvanKitov) Detection and location of small aftershocks using waveform cross correlation IvanKitov Aftershock sequences of earthquakes with magnitudes 5.0 and lower are difficult to detect and locate by sparse regional networks. Signals from aftershocks with magnitudes 2 to 3 are usually below detection thresholds of standard 3-C seismic stations at near regional distances. For seismic events close in space, the method waveform cross correlation (WCC) allows to reduce detection threshold by at least a unit of magnitude and to improve location precision to a few kilometres. Therefore, the WCC method is directly applicable to weak aftershock sequences. Here, we recover seismic activity after the earthquake near the town of Mariupol (Ukraine) occurred on August 7, 2016. The main shock was detected by many stations of the International monitoring system (IMS), including the closest primary IMS array stations AKASG (6.62 deg.) and BRTR (7.81), as well as 3-C station KBZ (5.00). The International data centre located this event (47.0013N, 37.5427E), estimated its origin time (08:15:4.1 UTC), magnitude (mb=4.5), and depth (6.8 km). This event was also detected by two array stations of the Institute for Dynamics of Geospheres (IDG) of the Russian Academy of Sciences (RAS): portable 3-C array RDON (3.28), which is the closest station, and MHVAR (7.96). Using signals from the main shock at five stations as waveform templates, we calculated continuous traces of cross correlation coefficient (CC) from the 7th to the 11th of August. We found that the best templates should include all regional phases, and thus, have the length from 80 s to 180 s. For detection, we used standard STA/LTA method with threshold depending on station. The accuracy of onset time estimation by the STA/LTA detector based on CC-traces is close to one sample, which varies from 0.05 s at BRTR to 0.005 s for RDON and MHVAR. Arrival times of all detected signals were reduced to origin times using the observed travel times from the main shock. Clusters of origin times are considered as event hypotheses in the phase association procedure. As a result, we found 12 aftershocks with magnitudes between 1.5 and 3.5. These small events were detected neither by the IDC nor by the near regional network of the Geophysical Survey of RAS, which has three closest 3-C stations at distances of 2.2 to 3.5 degrees from the studied earthquake. We also applied procedure of relative location and all aftershocks were found within a few km from the main shock. <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/mariupol-180109103054-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> Aftershock sequences of earthquakes with magnitudes 5.0 and lower are difficult to detect and locate by sparse regional networks. Signals from aftershocks with magnitudes 2 to 3 are usually below detection thresholds of standard 3-C seismic stations at near regional distances. For seismic events close in space, the method waveform cross correlation (WCC) allows to reduce detection threshold by at least a unit of magnitude and to improve location precision to a few kilometres. Therefore, the WCC method is directly applicable to weak aftershock sequences. Here, we recover seismic activity after the earthquake near the town of Mariupol (Ukraine) occurred on August 7, 2016. The main shock was detected by many stations of the International monitoring system (IMS), including the closest primary IMS array stations AKASG (6.62 deg.) and BRTR (7.81), as well as 3-C station KBZ (5.00). The International data centre located this event (47.0013N, 37.5427E), estimated its origin time (08:15:4.1 UTC), magnitude (mb=4.5), and depth (6.8 km). This event was also detected by two array stations of the Institute for Dynamics of Geospheres (IDG) of the Russian Academy of Sciences (RAS): portable 3-C array RDON (3.28), which is the closest station, and MHVAR (7.96). Using signals from the main shock at five stations as waveform templates, we calculated continuous traces of cross correlation coefficient (CC) from the 7th to the 11th of August. We found that the best templates should include all regional phases, and thus, have the length from 80 s to 180 s. For detection, we used standard STA/LTA method with threshold depending on station. The accuracy of onset time estimation by the STA/LTA detector based on CC-traces is close to one sample, which varies from 0.05 s at BRTR to 0.005 s for RDON and MHVAR. Arrival times of all detected signals were reduced to origin times using the observed travel times from the main shock. Clusters of origin times are considered as event hypotheses in the phase association procedure. As a result, we found 12 aftershocks with magnitudes between 1.5 and 3.5. These small events were detected neither by the IDC nor by the near regional network of the Geophysical Survey of RAS, which has three closest 3-C stations at distances of 2.2 to 3.5 degrees from the studied earthquake. We also applied procedure of relative location and all aftershocks were found within a few km from the main shock.
Detection and location of small aftershocks using waveform cross correlation from Ivan Kitov
]]> 101 2 https://cdn.slidesharecdn.com/ss_thumbnails/mariupol-180109103054-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 Waveform cross correlation: coherency of seismic signals estimated from repeated mining blasts /slideshow/waveform-cross-correlation-coherency-of-seismic-signals-estimated-from-repeated-mining-blasts/85905997 posterv3-180109102743
Waveform cross correlation (WCC) is an optimal detection technique for signals from spatially close seismic sources. Observations at various distances from a multitude of sources in a variety of seismotectonic and geological conditions demonstrate that signals from close events recorded at common stations are characterized by high level of similarity. Signals from remote sources are less similar mainly because of the variations in propagation paths. Different parts of a complete seismic wavetrain have different sensitivity to the propagation path. The initial part retains general characteristics of the source time function. The shape of later seismic phases is chiefly defined by propagation path. Here, we investigate the level of similarity between hundreds of signals generated by chemical blasts within a phosphate mine in Jordan and measured by 5 seismic stations at near-regional distances. We have revealed a much higher similarity of the first 3 s to 5 s of signals from different blasts, also at distances of about 20 km, at the same station as well as at different stations. This observation evidences in favour of high coherency in the initial part of signals at all stations. We also demonstrate that the observed coherency allows the use of very short (say, 3 s) waveform templates for detection and further phase association of signals based on cross correlation. Longer templates are characterized by larger overall signal specificity, which may reduce detection threshold and spatial resolution of the WCC method. However, different propagation paths within the same geological province may have similar transfer functions producing regular seismic phases with similar shapes independent on source position. This may increase the number of false detections from remote sources. We compare the performance of short and long waveform templates using detection statistics and the results of event hypotheses creation and further event location. ]]>
Waveform cross correlation (WCC) is an optimal detection technique for signals from spatially close seismic sources. Observations at various distances from a multitude of sources in a variety of seismotectonic and geological conditions demonstrate that signals from close events recorded at common stations are characterized by high level of similarity. Signals from remote sources are less similar mainly because of the variations in propagation paths. Different parts of a complete seismic wavetrain have different sensitivity to the propagation path. The initial part retains general characteristics of the source time function. The shape of later seismic phases is chiefly defined by propagation path. Here, we investigate the level of similarity between hundreds of signals generated by chemical blasts within a phosphate mine in Jordan and measured by 5 seismic stations at near-regional distances. We have revealed a much higher similarity of the first 3 s to 5 s of signals from different blasts, also at distances of about 20 km, at the same station as well as at different stations. This observation evidences in favour of high coherency in the initial part of signals at all stations. We also demonstrate that the observed coherency allows the use of very short (say, 3 s) waveform templates for detection and further phase association of signals based on cross correlation. Longer templates are characterized by larger overall signal specificity, which may reduce detection threshold and spatial resolution of the WCC method. However, different propagation paths within the same geological province may have similar transfer functions producing regular seismic phases with similar shapes independent on source position. This may increase the number of false detections from remote sources. We compare the performance of short and long waveform templates using detection statistics and the results of event hypotheses creation and further event location. ]]> Tue, 09 Jan 2018 10:27:43 GMT /slideshow/waveform-cross-correlation-coherency-of-seismic-signals-estimated-from-repeated-mining-blasts/85905997 IvanKitov@slideshare.net(IvanKitov) Waveform cross correlation: coherency of seismic signals estimated from repeated mining blasts IvanKitov Waveform cross correlation (WCC) is an optimal detection technique for signals from spatially close seismic sources. Observations at various distances from a multitude of sources in a variety of seismotectonic and geological conditions demonstrate that signals from close events recorded at common stations are characterized by high level of similarity. Signals from remote sources are less similar mainly because of the variations in propagation paths. Different parts of a complete seismic wavetrain have different sensitivity to the propagation path. The initial part retains general characteristics of the source time function. The shape of later seismic phases is chiefly defined by propagation path. Here, we investigate the level of similarity between hundreds of signals generated by chemical blasts within a phosphate mine in Jordan and measured by 5 seismic stations at near-regional distances. We have revealed a much higher similarity of the first 3 s to 5 s of signals from different blasts, also at distances of about 20 km, at the same station as well as at different stations. This observation evidences in favour of high coherency in the initial part of signals at all stations. We also demonstrate that the observed coherency allows the use of very short (say, 3 s) waveform templates for detection and further phase association of signals based on cross correlation. Longer templates are characterized by larger overall signal specificity, which may reduce detection threshold and spatial resolution of the WCC method. However, different propagation paths within the same geological province may have similar transfer functions producing regular seismic phases with similar shapes independent on source position. This may increase the number of false detections from remote sources. We compare the performance of short and long waveform templates using detection statistics and the results of event hypotheses creation and further event location. <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/posterv3-180109102743-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> Waveform cross correlation (WCC) is an optimal detection technique for signals from spatially close seismic sources. Observations at various distances from a multitude of sources in a variety of seismotectonic and geological conditions demonstrate that signals from close events recorded at common stations are characterized by high level of similarity. Signals from remote sources are less similar mainly because of the variations in propagation paths. Different parts of a complete seismic wavetrain have different sensitivity to the propagation path. The initial part retains general characteristics of the source time function. The shape of later seismic phases is chiefly defined by propagation path. Here, we investigate the level of similarity between hundreds of signals generated by chemical blasts within a phosphate mine in Jordan and measured by 5 seismic stations at near-regional distances. We have revealed a much higher similarity of the first 3 s to 5 s of signals from different blasts, also at distances of about 20 km, at the same station as well as at different stations. This observation evidences in favour of high coherency in the initial part of signals at all stations. We also demonstrate that the observed coherency allows the use of very short (say, 3 s) waveform templates for detection and further phase association of signals based on cross correlation. Longer templates are characterized by larger overall signal specificity, which may reduce detection threshold and spatial resolution of the WCC method. However, different propagation paths within the same geological province may have similar transfer functions producing regular seismic phases with similar shapes independent on source position. This may increase the number of false detections from remote sources. We compare the performance of short and long waveform templates using detection statistics and the results of event hypotheses creation and further event location.
Waveform cross correlation: coherency of seismic signals estimated from repeated mining blasts from Ivan Kitov
]]> 62 3 https://cdn.slidesharecdn.com/ss_thumbnails/posterv3-180109102743-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 Remote detection of weak aftershocks of the DPRK underground explosions using waveform cross correlation /slideshow/remote-detection-of-weak-aftershocks-of-the-dprk-underground-explosions-using-waveform-cross-correlation/85905907 aftershocks2-180109102551
We have estimated the performance of discrimination criterion based on the P/S spectral amplitude ratios obtained from six underground tests conducted by the DPRK since October 2006 and six aftershocks induced by the last two explosions. Two aftershocks were detected in routine processing at the International Data Centre of the Comprehensive Nuclear-Test-Ban Treaty Organization. Three aftershocks were detected by a prototype waveform cross correlation tool with explosions as master events, and one aftershock was found with the aftershocks as master events. Two seismic arrays USRK and KSRS of the International Monitoring System (IMS) and two non-IMS 3-component stations SEHB (South Korea) and MDJ (China) were used. With increasing frequency, all stations demonstrate approximately the same level of deviation between the Pg/Lg spectral amplitude ratios belonging to the DPRK explosions and their aftershocks. For a single station, simple statistical estimates show that the probability of any of six aftershocks not to be a sample from the explosion population is larger than 99.996% at the KSRS and even larger at USRK. The probability of any of the DPRK explosion to be a representative of the aftershock population is extremely small as defined by the distance of 20 and more standard deviations to the mean explosion Pg/Lg value. For network discrimination, we use the Mahalanobis distance combining the Pg/Lg estimates at three stations: USRK, KSRS and MDJ. At frequencies above 4 Hz, the (squared) Mahalanobis distance, D2, between the populations of explosions and aftershocks is larger than 100. In the frequency band between 6 and 12 Hz at USRK, the aftershocks distance from the average explosion D2>21,000. Statistically, the probability to mix up explosions and aftershocks is negligible. These discrimination results are related only to the aftershocks of the DPRK tests and cannot be directly extrapolated to the population of tectonic earthquakes in the same area. ]]>
We have estimated the performance of discrimination criterion based on the P/S spectral amplitude ratios obtained from six underground tests conducted by the DPRK since October 2006 and six aftershocks induced by the last two explosions. Two aftershocks were detected in routine processing at the International Data Centre of the Comprehensive Nuclear-Test-Ban Treaty Organization. Three aftershocks were detected by a prototype waveform cross correlation tool with explosions as master events, and one aftershock was found with the aftershocks as master events. Two seismic arrays USRK and KSRS of the International Monitoring System (IMS) and two non-IMS 3-component stations SEHB (South Korea) and MDJ (China) were used. With increasing frequency, all stations demonstrate approximately the same level of deviation between the Pg/Lg spectral amplitude ratios belonging to the DPRK explosions and their aftershocks. For a single station, simple statistical estimates show that the probability of any of six aftershocks not to be a sample from the explosion population is larger than 99.996% at the KSRS and even larger at USRK. The probability of any of the DPRK explosion to be a representative of the aftershock population is extremely small as defined by the distance of 20 and more standard deviations to the mean explosion Pg/Lg value. For network discrimination, we use the Mahalanobis distance combining the Pg/Lg estimates at three stations: USRK, KSRS and MDJ. At frequencies above 4 Hz, the (squared) Mahalanobis distance, D2, between the populations of explosions and aftershocks is larger than 100. In the frequency band between 6 and 12 Hz at USRK, the aftershocks distance from the average explosion D2>21,000. Statistically, the probability to mix up explosions and aftershocks is negligible. These discrimination results are related only to the aftershocks of the DPRK tests and cannot be directly extrapolated to the population of tectonic earthquakes in the same area. ]]> Tue, 09 Jan 2018 10:25:51 GMT /slideshow/remote-detection-of-weak-aftershocks-of-the-dprk-underground-explosions-using-waveform-cross-correlation/85905907 IvanKitov@slideshare.net(IvanKitov) Remote detection of weak aftershocks of the DPRK underground explosions using waveform cross correlation IvanKitov We have estimated the performance of discrimination criterion based on the P/S spectral amplitude ratios obtained from six underground tests conducted by the DPRK since October 2006 and six aftershocks induced by the last two explosions. Two aftershocks were detected in routine processing at the International Data Centre of the Comprehensive Nuclear-Test-Ban Treaty Organization. Three aftershocks were detected by a prototype waveform cross correlation tool with explosions as master events, and one aftershock was found with the aftershocks as master events. Two seismic arrays USRK and KSRS of the International Monitoring System (IMS) and two non-IMS 3-component stations SEHB (South Korea) and MDJ (China) were used. With increasing frequency, all stations demonstrate approximately the same level of deviation between the Pg/Lg spectral amplitude ratios belonging to the DPRK explosions and their aftershocks. For a single station, simple statistical estimates show that the probability of any of six aftershocks not to be a sample from the explosion population is larger than 99.996% at the KSRS and even larger at USRK. The probability of any of the DPRK explosion to be a representative of the aftershock population is extremely small as defined by the distance of 20 and more standard deviations to the mean explosion Pg/Lg value. For network discrimination, we use the Mahalanobis distance combining the Pg/Lg estimates at three stations: USRK, KSRS and MDJ. At frequencies above 4 Hz, the (squared) Mahalanobis distance, D2, between the populations of explosions and aftershocks is larger than 100. In the frequency band between 6 and 12 Hz at USRK, the aftershocks distance from the average explosion D2>21,000. Statistically, the probability to mix up explosions and aftershocks is negligible. These discrimination results are related only to the aftershocks of the DPRK tests and cannot be directly extrapolated to the population of tectonic earthquakes in the same area. <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/aftershocks2-180109102551-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> We have estimated the performance of discrimination criterion based on the P/S spectral amplitude ratios obtained from six underground tests conducted by the DPRK since October 2006 and six aftershocks induced by the last two explosions. Two aftershocks were detected in routine processing at the International Data Centre of the Comprehensive Nuclear-Test-Ban Treaty Organization. Three aftershocks were detected by a prototype waveform cross correlation tool with explosions as master events, and one aftershock was found with the aftershocks as master events. Two seismic arrays USRK and KSRS of the International Monitoring System (IMS) and two non-IMS 3-component stations SEHB (South Korea) and MDJ (China) were used. With increasing frequency, all stations demonstrate approximately the same level of deviation between the Pg/Lg spectral amplitude ratios belonging to the DPRK explosions and their aftershocks. For a single station, simple statistical estimates show that the probability of any of six aftershocks not to be a sample from the explosion population is larger than 99.996% at the KSRS and even larger at USRK. The probability of any of the DPRK explosion to be a representative of the aftershock population is extremely small as defined by the distance of 20 and more standard deviations to the mean explosion Pg/Lg value. For network discrimination, we use the Mahalanobis distance combining the Pg/Lg estimates at three stations: USRK, KSRS and MDJ. At frequencies above 4 Hz, the (squared) Mahalanobis distance, D2, between the populations of explosions and aftershocks is larger than 100. In the frequency band between 6 and 12 Hz at USRK, the aftershocks distance from the average explosion D2&gt;21,000. Statistically, the probability to mix up explosions and aftershocks is negligible. These discrimination results are related only to the aftershocks of the DPRK tests and cannot be directly extrapolated to the population of tectonic earthquakes in the same area.
Remote detection of weak aftershocks of the DPRK underground explosions using waveform cross correlation from Ivan Kitov
]]> 59 1 https://cdn.slidesharecdn.com/ss_thumbnails/aftershocks2-180109102551-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 Investigation of repeated events at Jordan phosphate mine with waveform cross cottelation /IvanKitov/investigation-of-repeated-events-at-jordan-phosphate-mine-with-waveform-cross-cottelation jordanmattsedit-170114204939
More than 1500 events were measured at 3 seismic stations. Their signals are processed using waveform cross correlation and Principal Component Analysis. The best waveforms and eigenvectors are used for detection. ]]>
More than 1500 events were measured at 3 seismic stations. Their signals are processed using waveform cross correlation and Principal Component Analysis. The best waveforms and eigenvectors are used for detection. ]]> Sat, 14 Jan 2017 20:49:39 GMT /IvanKitov/investigation-of-repeated-events-at-jordan-phosphate-mine-with-waveform-cross-cottelation IvanKitov@slideshare.net(IvanKitov) Investigation of repeated events at Jordan phosphate mine with waveform cross cottelation IvanKitov More than 1500 events were measured at 3 seismic stations. Their signals are processed using waveform cross correlation and Principal Component Analysis. The best waveforms and eigenvectors are used for detection. <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/jordanmattsedit-170114204939-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> More than 1500 events were measured at 3 seismic stations. Their signals are processed using waveform cross correlation and Principal Component Analysis. The best waveforms and eigenvectors are used for detection.
Investigation of repeated events at Jordan phosphate mine with waveform cross cottelation from Ivan Kitov
]]> 61 4 https://cdn.slidesharecdn.com/ss_thumbnails/jordanmattsedit-170114204939-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 Investigation of repeated blasts at Aitik mine using waveform cross correlation /slideshow/investigation-of-repeated-blasts-at-aitik-mine-using-waveform-cross-correlation/71020387 aitikkitovnikmat-170114204430
We present results of signal detection from repeated events at the Aitik and Kiruna mines in Sweden as based on waveform cross correlation. Several advanced methods based on tensor Singular Value Decomposition is applied to waveforms measured at seismic array ARCES, which consists of three-component sensors.]]>
We present results of signal detection from repeated events at the Aitik and Kiruna mines in Sweden as based on waveform cross correlation. Several advanced methods based on tensor Singular Value Decomposition is applied to waveforms measured at seismic array ARCES, which consists of three-component sensors.]]> Sat, 14 Jan 2017 20:44:30 GMT /slideshow/investigation-of-repeated-blasts-at-aitik-mine-using-waveform-cross-correlation/71020387 IvanKitov@slideshare.net(IvanKitov) Investigation of repeated blasts at Aitik mine using waveform cross correlation IvanKitov We present results of signal detection from repeated events at the Aitik and Kiruna mines in Sweden as based on waveform cross correlation. Several advanced methods based on tensor Singular Value Decomposition is applied to waveforms measured at seismic array ARCES, which consists of three-component sensors. <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/aitikkitovnikmat-170114204430-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> We present results of signal detection from repeated events at the Aitik and Kiruna mines in Sweden as based on waveform cross correlation. Several advanced methods based on tensor Singular Value Decomposition is applied to waveforms measured at seismic array ARCES, which consists of three-component sensors.
Investigation of repeated blasts at Aitik mine using waveform cross correlation from Ivan Kitov
]]> 68 4 https://cdn.slidesharecdn.com/ss_thumbnails/aitikkitovnikmat-170114204430-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 Recovery of aftershock sequences using waveform cross correlation: from catastrophic earthquakes to smallest aftershocks /slideshow/aftershock-tool-2016/71020353 aftershocktool2016-170114204212
Description of a software package for signal detection and association using waveform cross correlation. Recovery of aftershock sequences of the largest events: Sumatra 2004 and Tohoku 2011. Finding of a small aftershock of the September 9, 2016 DPRK test.]]>
Description of a software package for signal detection and association using waveform cross correlation. Recovery of aftershock sequences of the largest events: Sumatra 2004 and Tohoku 2011. Finding of a small aftershock of the September 9, 2016 DPRK test.]]> Sat, 14 Jan 2017 20:42:12 GMT /slideshow/aftershock-tool-2016/71020353 IvanKitov@slideshare.net(IvanKitov) Recovery of aftershock sequences using waveform cross correlation: from catastrophic earthquakes to smallest aftershocks IvanKitov Description of a software package for signal detection and association using waveform cross correlation. Recovery of aftershock sequences of the largest events: Sumatra 2004 and Tohoku 2011. Finding of a small aftershock of the September 9, 2016 DPRK test. <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/aftershocktool2016-170114204212-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> Description of a software package for signal detection and association using waveform cross correlation. Recovery of aftershock sequences of the largest events: Sumatra 2004 and Tohoku 2011. Finding of a small aftershock of the September 9, 2016 DPRK test.
Recovery of aftershock sequences using waveform cross correlation: from catastrophic earthquakes to smallest aftershocks from Ivan Kitov
]]> 95 4 https://cdn.slidesharecdn.com/ss_thumbnails/aftershocktool2016-170114204212-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 Testing the global grid of master events for waveform cross correlation with the Reviewed Event Bulletin /slideshow/gg-2015final/49969913 gg2015-150629180344-lva1-app6891
Abstract The Comprehensive Nuclear-Test-Ban Treatys verification regime requires uniform distribution of monitoring capabilities over the globe. The use of waveform cross correlation as a monitoring technique demands waveform templates from master events outside regions of natural seismicity and test sites. We populated aseismic areas with masters having synthetic templates for predefined sets (from 3 to 10) of primary array stations of the International Monitoring System. Previously, we tested the global set of master events and synthetic templates using IMS seismic data for February 12, 2013 and demonstrated excellent detection and location capability of the matched filter technique. In this study, we test the global grid of synthetic master events using seismic events from the Reviewed Event Bulletin. For detection, we use standard STA/LTA (SNR) procedure applied to the time series of cross correlation coefficient (CC). Phase association is based on SNR, CC, and arrival times. Azimuth and slowness estimates based f-k analysis cross correlation traces are used to reject false arrivals.]]>
Abstract The Comprehensive Nuclear-Test-Ban Treatys verification regime requires uniform distribution of monitoring capabilities over the globe. The use of waveform cross correlation as a monitoring technique demands waveform templates from master events outside regions of natural seismicity and test sites. We populated aseismic areas with masters having synthetic templates for predefined sets (from 3 to 10) of primary array stations of the International Monitoring System. Previously, we tested the global set of master events and synthetic templates using IMS seismic data for February 12, 2013 and demonstrated excellent detection and location capability of the matched filter technique. In this study, we test the global grid of synthetic master events using seismic events from the Reviewed Event Bulletin. For detection, we use standard STA/LTA (SNR) procedure applied to the time series of cross correlation coefficient (CC). Phase association is based on SNR, CC, and arrival times. Azimuth and slowness estimates based f-k analysis cross correlation traces are used to reject false arrivals.]]> Mon, 29 Jun 2015 18:03:44 GMT /slideshow/gg-2015final/49969913 IvanKitov@slideshare.net(IvanKitov) Testing the global grid of master events for waveform cross correlation with the Reviewed Event Bulletin IvanKitov Abstract The Comprehensive Nuclear-Test-Ban Treatys verification regime requires uniform distribution of monitoring capabilities over the globe. The use of waveform cross correlation as a monitoring technique demands waveform templates from master events outside regions of natural seismicity and test sites. We populated aseismic areas with masters having synthetic templates for predefined sets (from 3 to 10) of primary array stations of the International Monitoring System. Previously, we tested the global set of master events and synthetic templates using IMS seismic data for February 12, 2013 and demonstrated excellent detection and location capability of the matched filter technique. In this study, we test the global grid of synthetic master events using seismic events from the Reviewed Event Bulletin. For detection, we use standard STA/LTA (SNR) procedure applied to the time series of cross correlation coefficient (CC). Phase association is based on SNR, CC, and arrival times. Azimuth and slowness estimates based f-k analysis cross correlation traces are used to reject false arrivals. <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/gg2015-150629180344-lva1-app6891-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> Abstract The Comprehensive Nuclear-Test-Ban Treatys verification regime requires uniform distribution of monitoring capabilities over the globe. The use of waveform cross correlation as a monitoring technique demands waveform templates from master events outside regions of natural seismicity and test sites. We populated aseismic areas with masters having synthetic templates for predefined sets (from 3 to 10) of primary array stations of the International Monitoring System. Previously, we tested the global set of master events and synthetic templates using IMS seismic data for February 12, 2013 and demonstrated excellent detection and location capability of the matched filter technique. In this study, we test the global grid of synthetic master events using seismic events from the Reviewed Event Bulletin. For detection, we use standard STA/LTA (SNR) procedure applied to the time series of cross correlation coefficient (CC). Phase association is based on SNR, CC, and arrival times. Azimuth and slowness estimates based f-k analysis cross correlation traces are used to reject false arrivals.
Testing the global grid of master events for waveform cross correlation with the Reviewed Event Bulletin from Ivan Kitov
]]> 230 1 https://cdn.slidesharecdn.com/ss_thumbnails/gg2015-150629180344-lva1-app6891-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 Detection of the 2006 DPRK event using small aperture array Mikhnevo /slideshow/detection-of-the-2006-dprk-event-using-small-a/49969832 dprk-150629180102-lva1-app6891
We use repeating events at the DPRK test site in order to detect the ultra-weak signal at the Mikhnevo array by using waveform cross correlation]]>
We use repeating events at the DPRK test site in order to detect the ultra-weak signal at the Mikhnevo array by using waveform cross correlation]]> Mon, 29 Jun 2015 18:01:02 GMT /slideshow/detection-of-the-2006-dprk-event-using-small-a/49969832 IvanKitov@slideshare.net(IvanKitov) Detection of the 2006 DPRK event using small aperture array Mikhnevo IvanKitov We use repeating events at the DPRK test site in order to detect the ultra-weak signal at the Mikhnevo array by using waveform cross correlation <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/dprk-150629180102-lva1-app6891-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> We use repeating events at the DPRK test site in order to detect the ultra-weak signal at the Mikhnevo array by using waveform cross correlation
Detection of the 2006 DPRK event using small aperture array Mikhnevo from Ivan Kitov
]]> 201 4 https://cdn.slidesharecdn.com/ss_thumbnails/dprk-150629180102-lva1-app6891-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 The use of a 3-C array for regional monitoring /slideshow/3-carray/49969733 3carray-150629175823-lva1-app6891
The advantage of a 3-C array in detection and waveform cross correlation]]>
The advantage of a 3-C array in detection and waveform cross correlation]]> Mon, 29 Jun 2015 17:58:23 GMT /slideshow/3-carray/49969733 IvanKitov@slideshare.net(IvanKitov) The use of a 3-C array for regional monitoring IvanKitov The advantage of a 3-C array in detection and waveform cross correlation <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/3carray-150629175823-lva1-app6891-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> The advantage of a 3-C array in detection and waveform cross correlation
The use of a 3-C array for regional monitoring from Ivan Kitov
]]> 254 4 https://cdn.slidesharecdn.com/ss_thumbnails/3carray-150629175823-lva1-app6891-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 The use of waveform cross correlation for creation of an accurate catalogue of mining explosions within the Russian platform using joint capabilities of seismic array Mikhnevo and IMS arrays /slideshow/the-use-of-waveform-cross-correlation-for-creation-of-an-accurate-catalogue-of-mining-explosions-within-the-russian-platform-using-joint-capabilities-of-seismic-array-mikhnevo-and-ims-arrays/42840402 mikhnevo-141218111913-conversion-gate02
Page 3 In the current study of mining activity within the Russian platform, we use the advantages of location and historical bulletins/catalogues of mining explosions recorded by small-aperture seismic array Mikhnevo (MHVAR). The Institute of Geospheres Dynamics (IDG) of the Russian Academy of Sciences runs seismic array MHVAR (54.950N; 37.767E) since 2004. Small-aperture seismic array Mikhnevo includes ten vertical stations (solid triangles), with one station in the geometrical centre of the array (C00) and other nine stations distributed over three circles with radii of 130 m, 320 m, and 600 m. The array aperture in approximately 1.1 km. Two 3C stations (solid triangles in circles) were added to the outer circle in order to improve the overall stations sensitivity (detection threshold) and resolution. All stations are equipped with short-period seismometers SM3-KV, which are characterized by flat response between 0.8 Hz and 30 Hz and gain of 180,000 [Vs/m]. Later, a 3C broad band station (BB) was installed in the centre of the array for surface wave measurements. The array response function (only for 12 vertical channels) is similar to that for many small-aperture arrays. Such arrays are designed to measure high-frequency signals from regional and near-regional sources with magnitudes above 1.5-2.0. Page 4 MHVAR detects regional seismic phases (Pn, Sn, Lg, Rg) from various sources. Figure shows some selected waveforms with source-station distance decreasing up-down. Correspondingly the length of records decreases for the closest mines its harder to distinguish between P and S phases. Page 5 More than 50 areas at regional and near regional distances with different levels of mining activity have been identified by MHVAR. Since 2004, thousands of events have been reported in the IDG seismic catalogue as mining explosions. The IDG publishes this mining event catalogue as a part of the annual issues of Earthquakes in Russia, which is available for the broader geophysical community. The map shows several selected mines at near-regional distances where MHVAR successfully detects events with magnitudes 1.0 and lower. We also show a few selected mines at regional distances with the largest events of magnitude (ML) 2.0 and above. Such events should be also detected by IMS arrays. Joint interpretation of signals detected by MHVAR and IMS arrays allows significant improvements in signal detection, location, characterization and identification of events in the IDG catalogue when the historical data are revisited. The work on joint analysis of the IDG and IMS data is possible under the Contract for limited access to IMS data and IDC products between the CTBTO and IDG, which allows obtaining data through 2011. To begin with, we have chosen blasts with larger magnitudes from well-known ironstone mine Mikhailovskiy (red circle), which is situated at regional distances somewhere between MHVAR (~330 km) and IMS array AKASG]]>
Page 3 In the current study of mining activity within the Russian platform, we use the advantages of location and historical bulletins/catalogues of mining explosions recorded by small-aperture seismic array Mikhnevo (MHVAR). The Institute of Geospheres Dynamics (IDG) of the Russian Academy of Sciences runs seismic array MHVAR (54.950N; 37.767E) since 2004. Small-aperture seismic array Mikhnevo includes ten vertical stations (solid triangles), with one station in the geometrical centre of the array (C00) and other nine stations distributed over three circles with radii of 130 m, 320 m, and 600 m. The array aperture in approximately 1.1 km. Two 3C stations (solid triangles in circles) were added to the outer circle in order to improve the overall stations sensitivity (detection threshold) and resolution. All stations are equipped with short-period seismometers SM3-KV, which are characterized by flat response between 0.8 Hz and 30 Hz and gain of 180,000 [Vs/m]. Later, a 3C broad band station (BB) was installed in the centre of the array for surface wave measurements. The array response function (only for 12 vertical channels) is similar to that for many small-aperture arrays. Such arrays are designed to measure high-frequency signals from regional and near-regional sources with magnitudes above 1.5-2.0. Page 4 MHVAR detects regional seismic phases (Pn, Sn, Lg, Rg) from various sources. Figure shows some selected waveforms with source-station distance decreasing up-down. Correspondingly the length of records decreases for the closest mines its harder to distinguish between P and S phases. Page 5 More than 50 areas at regional and near regional distances with different levels of mining activity have been identified by MHVAR. Since 2004, thousands of events have been reported in the IDG seismic catalogue as mining explosions. The IDG publishes this mining event catalogue as a part of the annual issues of Earthquakes in Russia, which is available for the broader geophysical community. The map shows several selected mines at near-regional distances where MHVAR successfully detects events with magnitudes 1.0 and lower. We also show a few selected mines at regional distances with the largest events of magnitude (ML) 2.0 and above. Such events should be also detected by IMS arrays. Joint interpretation of signals detected by MHVAR and IMS arrays allows significant improvements in signal detection, location, characterization and identification of events in the IDG catalogue when the historical data are revisited. The work on joint analysis of the IDG and IMS data is possible under the Contract for limited access to IMS data and IDC products between the CTBTO and IDG, which allows obtaining data through 2011. To begin with, we have chosen blasts with larger magnitudes from well-known ironstone mine Mikhailovskiy (red circle), which is situated at regional distances somewhere between MHVAR (~330 km) and IMS array AKASG]]> Thu, 18 Dec 2014 11:19:13 GMT /slideshow/the-use-of-waveform-cross-correlation-for-creation-of-an-accurate-catalogue-of-mining-explosions-within-the-russian-platform-using-joint-capabilities-of-seismic-array-mikhnevo-and-ims-arrays/42840402 IvanKitov@slideshare.net(IvanKitov) The use of waveform cross correlation for creation of an accurate catalogue of mining explosions within the Russian platform using joint capabilities of seismic array Mikhnevo and IMS arrays IvanKitov Page 3 In the current study of mining activity within the Russian platform, we use the advantages of location and historical bulletins/catalogues of mining explosions recorded by small-aperture seismic array Mikhnevo (MHVAR). The Institute of Geospheres Dynamics (IDG) of the Russian Academy of Sciences runs seismic array MHVAR (54.950N; 37.767E) since 2004. Small-aperture seismic array Mikhnevo includes ten vertical stations (solid triangles), with one station in the geometrical centre of the array (C00) and other nine stations distributed over three circles with radii of 130 m, 320 m, and 600 m. The array aperture in approximately 1.1 km. Two 3C stations (solid triangles in circles) were added to the outer circle in order to improve the overall stations sensitivity (detection threshold) and resolution. All stations are equipped with short-period seismometers SM3-KV, which are characterized by flat response between 0.8 Hz and 30 Hz and gain of 180,000 [Vs/m]. Later, a 3C broad band station (BB) was installed in the centre of the array for surface wave measurements. The array response function (only for 12 vertical channels) is similar to that for many small-aperture arrays. Such arrays are designed to measure high-frequency signals from regional and near-regional sources with magnitudes above 1.5-2.0. Page 4 MHVAR detects regional seismic phases (Pn, Sn, Lg, Rg) from various sources. Figure shows some selected waveforms with source-station distance decreasing up-down. Correspondingly the length of records decreases for the closest mines its harder to distinguish between P and S phases. Page 5 More than 50 areas at regional and near regional distances with different levels of mining activity have been identified by MHVAR. Since 2004, thousands of events have been reported in the IDG seismic catalogue as mining explosions. The IDG publishes this mining event catalogue as a part of the annual issues of Earthquakes in Russia, which is available for the broader geophysical community. The map shows several selected mines at near-regional distances where MHVAR successfully detects events with magnitudes 1.0 and lower. We also show a few selected mines at regional distances with the largest events of magnitude (ML) 2.0 and above. Such events should be also detected by IMS arrays. Joint interpretation of signals detected by MHVAR and IMS arrays allows significant improvements in signal detection, location, characterization and identification of events in the IDG catalogue when the historical data are revisited. The work on joint analysis of the IDG and IMS data is possible under the Contract for limited access to IMS data and IDC products between the CTBTO and IDG, which allows obtaining data through 2011. To begin with, we have chosen blasts with larger magnitudes from well-known ironstone mine Mikhailovskiy (red circle), which is situated at regional distances somewhere between MHVAR (~330 km) and IMS array AKASG <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/mikhnevo-141218111913-conversion-gate02-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> Page 3 In the current study of mining activity within the Russian platform, we use the advantages of location and historical bulletins/catalogues of mining explosions recorded by small-aperture seismic array Mikhnevo (MHVAR). The Institute of Geospheres Dynamics (IDG) of the Russian Academy of Sciences runs seismic array MHVAR (54.950N; 37.767E) since 2004. Small-aperture seismic array Mikhnevo includes ten vertical stations (solid triangles), with one station in the geometrical centre of the array (C00) and other nine stations distributed over three circles with radii of 130 m, 320 m, and 600 m. The array aperture in approximately 1.1 km. Two 3C stations (solid triangles in circles) were added to the outer circle in order to improve the overall stations sensitivity (detection threshold) and resolution. All stations are equipped with short-period seismometers SM3-KV, which are characterized by flat response between 0.8 Hz and 30 Hz and gain of 180,000 [Vs/m]. Later, a 3C broad band station (BB) was installed in the centre of the array for surface wave measurements. The array response function (only for 12 vertical channels) is similar to that for many small-aperture arrays. Such arrays are designed to measure high-frequency signals from regional and near-regional sources with magnitudes above 1.5-2.0. Page 4 MHVAR detects regional seismic phases (Pn, Sn, Lg, Rg) from various sources. Figure shows some selected waveforms with source-station distance decreasing up-down. Correspondingly the length of records decreases for the closest mines its harder to distinguish between P and S phases. Page 5 More than 50 areas at regional and near regional distances with different levels of mining activity have been identified by MHVAR. Since 2004, thousands of events have been reported in the IDG seismic catalogue as mining explosions. The IDG publishes this mining event catalogue as a part of the annual issues of Earthquakes in Russia, which is available for the broader geophysical community. The map shows several selected mines at near-regional distances where MHVAR successfully detects events with magnitudes 1.0 and lower. We also show a few selected mines at regional distances with the largest events of magnitude (ML) 2.0 and above. Such events should be also detected by IMS arrays. Joint interpretation of signals detected by MHVAR and IMS arrays allows significant improvements in signal detection, location, characterization and identification of events in the IDG catalogue when the historical data are revisited. The work on joint analysis of the IDG and IMS data is possible under the Contract for limited access to IMS data and IDC products between the CTBTO and IDG, which allows obtaining data through 2011. To begin with, we have chosen blasts with larger magnitudes from well-known ironstone mine Mikhailovskiy (red circle), which is situated at regional distances somewhere between MHVAR (~330 km) and IMS array AKASG
The use of waveform cross correlation for creation of an accurate catalogue of mining explosions within the Russian platform using joint capabilities of seismic array Mikhnevo and IMS arrays from Ivan Kitov
]]> 464 1 https://cdn.slidesharecdn.com/ss_thumbnails/mikhnevo-141218111913-conversion-gate02-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 Inflation, Unemployment, and Labor Force: The Phillips Curve and Long-term Projections for Japan /slideshow/1814-kitov-poster/41096757 1814kitovposter-141104052028-conversion-gate02
Inflation, Unemployment, and Labor Force: The Phillips Curve and Long-term Projections for Japan presented at Euro Area Business Cycle Network (EABCN) Inflation Developments after the Great Recession Eltville (Frankfurt), 6-7 December 2013 Hosted by the Deutsche Bundesbank; Sponsored by the EABCN]]>
Inflation, Unemployment, and Labor Force: The Phillips Curve and Long-term Projections for Japan presented at Euro Area Business Cycle Network (EABCN) Inflation Developments after the Great Recession Eltville (Frankfurt), 6-7 December 2013 Hosted by the Deutsche Bundesbank; Sponsored by the EABCN]]> Tue, 04 Nov 2014 05:20:28 GMT /slideshow/1814-kitov-poster/41096757 IvanKitov@slideshare.net(IvanKitov) Inflation, Unemployment, and Labor Force: The Phillips Curve and Long-term Projections for Japan IvanKitov Inflation, Unemployment, and Labor Force: The Phillips Curve and Long-term Projections for Japan presented at Euro Area Business Cycle Network (EABCN) Inflation Developments after the Great Recession Eltville (Frankfurt), 6-7 December 2013 Hosted by the Deutsche Bundesbank; Sponsored by the EABCN <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/1814kitovposter-141104052028-conversion-gate02-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> Inflation, Unemployment, and Labor Force: The Phillips Curve and Long-term Projections for Japan presented at Euro Area Business Cycle Network (EABCN) Inflation Developments after the Great Recession Eltville (Frankfurt), 6-7 December 2013 Hosted by the Deutsche Bundesbank; Sponsored by the EABCN
Inflation, Unemployment, and Labor Force: The Phillips Curve and Long-term Projections for Japan from Ivan Kitov
]]> 335 3 https://cdn.slidesharecdn.com/ss_thumbnails/1814kitovposter-141104052028-conversion-gate02-thumbnail.jpg?width=120&height=120&fit=bounds document Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 Big Data solution for CTBT monitoring:CEA-IDC joint global cross correlation project /slideshow/big-data-solution-for-ctbt-monitoringceaidc-joint-global-cross-correlation-project/34706442 ceaidc1-140515004819-phpapp01
Cross correlation of seismic waveforms from the IDC 15-year archive needs a BigData solution. Joint efforts are aimed at solving scientific and technical problems/]]>
Cross correlation of seismic waveforms from the IDC 15-year archive needs a BigData solution. Joint efforts are aimed at solving scientific and technical problems/]]> Thu, 15 May 2014 00:48:19 GMT /slideshow/big-data-solution-for-ctbt-monitoringceaidc-joint-global-cross-correlation-project/34706442 IvanKitov@slideshare.net(IvanKitov) Big Data solution for CTBT monitoring:CEA-IDC joint global cross correlation project IvanKitov Cross correlation of seismic waveforms from the IDC 15-year archive needs a BigData solution. Joint efforts are aimed at solving scientific and technical problems/ <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/ceaidc1-140515004819-phpapp01-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> Cross correlation of seismic waveforms from the IDC 15-year archive needs a BigData solution. Joint efforts are aimed at solving scientific and technical problems/
Big Data solution for CTBT monitoring:CEA-IDC joint global cross correlation project from Ivan Kitov
]]> 395 5 https://cdn.slidesharecdn.com/ss_thumbnails/ceaidc1-140515004819-phpapp01-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 Joint interpretation of infrasound, acoustic, and seismic waves from meteorites: Chelyabinsk bolide and other events /slideshow/joint-interpretation-of-infrasound-acoustic-and-seismic-waves-from-meteorites-chelyabinsk-bolide-and-other/34706234 rozhkovmeteoriteegu-2014-140515003946-phpapp01
Sources of signals Peak energy release. Acoustic (low-amplitude shock) wave Infrasound source vs. seismic source Seismic waves: Pn, Lg Acousto-seismic waves: LR, LQ Comparison with atmospheric nuclear tests: Love and Rayleigh waves Comparison with the 1987 Chulym meteorite ]]>
Sources of signals Peak energy release. Acoustic (low-amplitude shock) wave Infrasound source vs. seismic source Seismic waves: Pn, Lg Acousto-seismic waves: LR, LQ Comparison with atmospheric nuclear tests: Love and Rayleigh waves Comparison with the 1987 Chulym meteorite ]]> Thu, 15 May 2014 00:39:46 GMT /slideshow/joint-interpretation-of-infrasound-acoustic-and-seismic-waves-from-meteorites-chelyabinsk-bolide-and-other/34706234 IvanKitov@slideshare.net(IvanKitov) Joint interpretation of infrasound, acoustic, and seismic waves from meteorites: Chelyabinsk bolide and other events IvanKitov Sources of signals Peak energy release. Acoustic (low-amplitude shock) wave Infrasound source vs. seismic source Seismic waves: Pn, Lg Acousto-seismic waves: LR, LQ Comparison with atmospheric nuclear tests: Love and Rayleigh waves Comparison with the 1987 Chulym meteorite <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/rozhkovmeteoriteegu-2014-140515003946-phpapp01-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> Sources of signals Peak energy release. Acoustic (low-amplitude shock) wave Infrasound source vs. seismic source Seismic waves: Pn, Lg Acousto-seismic waves: LR, LQ Comparison with atmospheric nuclear tests: Love and Rayleigh waves Comparison with the 1987 Chulym meteorite
Joint interpretation of infrasound, acoustic, and seismic waves from meteorites: Chelyabinsk bolide and other events from Ivan Kitov
]]> 484 4 https://cdn.slidesharecdn.com/ss_thumbnails/rozhkovmeteoriteegu-2014-140515003946-phpapp01-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 The Chelyabinsk meteor: joint interpretation of infrasound, acoustic, and seismic waves /slideshow/the-chelyabinsk-meteor-joint-interpretation/29378611 rozhkovmeteoritefin5-131220003559-phpapp01
- Peak energy release. Acoustic (low-amplitude shock) wave - Infrasound source vs. seismic source - Seismic waves: Pn, Lg - Acousto-seismic waves: LR, LQ - Comparison with atmospheric nuclear tests: Love and Rayleigh waves - Comparison with the 1987 Chulym meteorite ]]>
- Peak energy release. Acoustic (low-amplitude shock) wave - Infrasound source vs. seismic source - Seismic waves: Pn, Lg - Acousto-seismic waves: LR, LQ - Comparison with atmospheric nuclear tests: Love and Rayleigh waves - Comparison with the 1987 Chulym meteorite ]]> Fri, 20 Dec 2013 00:35:59 GMT /slideshow/the-chelyabinsk-meteor-joint-interpretation/29378611 IvanKitov@slideshare.net(IvanKitov) The Chelyabinsk meteor: joint interpretation of infrasound, acoustic, and seismic waves IvanKitov - Peak energy release. Acoustic (low-amplitude shock) wave - Infrasound source vs. seismic source - Seismic waves: Pn, Lg - Acousto-seismic waves: LR, LQ - Comparison with atmospheric nuclear tests: Love and Rayleigh waves - Comparison with the 1987 Chulym meteorite <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/rozhkovmeteoritefin5-131220003559-phpapp01-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> - Peak energy release. Acoustic (low-amplitude shock) wave - Infrasound source vs. seismic source - Seismic waves: Pn, Lg - Acousto-seismic waves: LR, LQ - Comparison with atmospheric nuclear tests: Love and Rayleigh waves - Comparison with the 1987 Chulym meteorite
The Chelyabinsk meteor: joint interpretation of infrasound, acoustic, and seismic waves from Ivan Kitov
]]> 1352 4 https://cdn.slidesharecdn.com/ss_thumbnails/rozhkovmeteoritefin5-131220003559-phpapp01-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 Synthetics vs. real waveforms from underground nuclear explosions as master templates for CTBT monitoring with cross-correlation /slideshow/synthetics-vs-real-waveforms-from-underground-nuclear-explosions-as-master-templates-for-ctbt-monitoring-with-crosscorrelation/29330743 gt-12fin-131218125501-phpapp01
The cross-correlation (CC) and master event technique is efficient in Comprehensive Nuclear-Test Ban Treaty (CTBT) monitoring. Two primary goals of CTBT monitoring are detection and location of nuclear explosions. Therefore, the CC monitoring should be focused on finding such events. The use of physically adequate masters may increase the number of valid events in the Reviewed Event Bulletin (REB) of the International Data Centre by a factor of 2. Inadequate master events may increase the number of irrelevant events in REB and reduce the sensitivity of the CC technique to valid events. In order to cover the entire earth, including vast aseismic territories, with the CC based nuclear test monitoring we conducted a thorough research and defined the most appropriate real and synthetic master events representing underground explosion sources. A procedure was developed on optimizing the master event simulation based on principal component analysis with bootstrap aggregation as a dimension reduction technique narrowing the classes of CC templates used in detection and location process. Actual waveforms and metadata from the DTRA Verification Database were used to validate our approach. The detection and location results based on real and synthetic master events were compared. ]]>
The cross-correlation (CC) and master event technique is efficient in Comprehensive Nuclear-Test Ban Treaty (CTBT) monitoring. Two primary goals of CTBT monitoring are detection and location of nuclear explosions. Therefore, the CC monitoring should be focused on finding such events. The use of physically adequate masters may increase the number of valid events in the Reviewed Event Bulletin (REB) of the International Data Centre by a factor of 2. Inadequate master events may increase the number of irrelevant events in REB and reduce the sensitivity of the CC technique to valid events. In order to cover the entire earth, including vast aseismic territories, with the CC based nuclear test monitoring we conducted a thorough research and defined the most appropriate real and synthetic master events representing underground explosion sources. A procedure was developed on optimizing the master event simulation based on principal component analysis with bootstrap aggregation as a dimension reduction technique narrowing the classes of CC templates used in detection and location process. Actual waveforms and metadata from the DTRA Verification Database were used to validate our approach. The detection and location results based on real and synthetic master events were compared. ]]> Wed, 18 Dec 2013 12:55:01 GMT /slideshow/synthetics-vs-real-waveforms-from-underground-nuclear-explosions-as-master-templates-for-ctbt-monitoring-with-crosscorrelation/29330743 IvanKitov@slideshare.net(IvanKitov) Synthetics vs. real waveforms from underground nuclear explosions as master templates for CTBT monitoring with cross-correlation IvanKitov The cross-correlation (CC) and master event technique is efficient in Comprehensive Nuclear-Test Ban Treaty (CTBT) monitoring. Two primary goals of CTBT monitoring are detection and location of nuclear explosions. Therefore, the CC monitoring should be focused on finding such events. The use of physically adequate masters may increase the number of valid events in the Reviewed Event Bulletin (REB) of the International Data Centre by a factor of 2. Inadequate master events may increase the number of irrelevant events in REB and reduce the sensitivity of the CC technique to valid events. In order to cover the entire earth, including vast aseismic territories, with the CC based nuclear test monitoring we conducted a thorough research and defined the most appropriate real and synthetic master events representing underground explosion sources. A procedure was developed on optimizing the master event simulation based on principal component analysis with bootstrap aggregation as a dimension reduction technique narrowing the classes of CC templates used in detection and location process. Actual waveforms and metadata from the DTRA Verification Database were used to validate our approach. The detection and location results based on real and synthetic master events were compared. <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/gt-12fin-131218125501-phpapp01-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> The cross-correlation (CC) and master event technique is efficient in Comprehensive Nuclear-Test Ban Treaty (CTBT) monitoring. Two primary goals of CTBT monitoring are detection and location of nuclear explosions. Therefore, the CC monitoring should be focused on finding such events. The use of physically adequate masters may increase the number of valid events in the Reviewed Event Bulletin (REB) of the International Data Centre by a factor of 2. Inadequate master events may increase the number of irrelevant events in REB and reduce the sensitivity of the CC technique to valid events. In order to cover the entire earth, including vast aseismic territories, with the CC based nuclear test monitoring we conducted a thorough research and defined the most appropriate real and synthetic master events representing underground explosion sources. A procedure was developed on optimizing the master event simulation based on principal component analysis with bootstrap aggregation as a dimension reduction technique narrowing the classes of CC templates used in detection and location process. Actual waveforms and metadata from the DTRA Verification Database were used to validate our approach. The detection and location results based on real and synthetic master events were compared.
Synthetics vs. real waveforms from underground nuclear explosions as master templates for CTBT monitoring with cross-correlation from Ivan Kitov
]]> 400 4 https://cdn.slidesharecdn.com/ss_thumbnails/gt-12fin-131218125501-phpapp01-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 Performance of waveform cross correlation using a global and regular grid of master events /slideshow/rozhkov-global-grid/29330534 rozhkovglobalgrid-131218124754-phpapp02
Outline 1.Motivation 2.Global seismic monitoring: IMS 3.Global seismicity: IDC view 4.Global cross correlation grid: a design 5.Cross correlation at teleseismic distances 6.Underground nuclear explosions as master events 7.Synthetic master events 8.Principal and Independent Component Analysis 9.Testing with world seismicity of February 12, 2013 10. DPRK 2013 of February 12, 2013]]>
Outline 1.Motivation 2.Global seismic monitoring: IMS 3.Global seismicity: IDC view 4.Global cross correlation grid: a design 5.Cross correlation at teleseismic distances 6.Underground nuclear explosions as master events 7.Synthetic master events 8.Principal and Independent Component Analysis 9.Testing with world seismicity of February 12, 2013 10. DPRK 2013 of February 12, 2013]]> Wed, 18 Dec 2013 12:47:54 GMT /slideshow/rozhkov-global-grid/29330534 IvanKitov@slideshare.net(IvanKitov) Performance of waveform cross correlation using a global and regular grid of master events IvanKitov Outline 1.Motivation 2.Global seismic monitoring: IMS 3.Global seismicity: IDC view 4.Global cross correlation grid: a design 5.Cross correlation at teleseismic distances 6.Underground nuclear explosions as master events 7.Synthetic master events 8.Principal and Independent Component Analysis 9.Testing with world seismicity of February 12, 2013 10. DPRK 2013 of February 12, 2013 <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/rozhkovglobalgrid-131218124754-phpapp02-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> Outline 1.Motivation 2.Global seismic monitoring: IMS 3.Global seismicity: IDC view 4.Global cross correlation grid: a design 5.Cross correlation at teleseismic distances 6.Underground nuclear explosions as master events 7.Synthetic master events 8.Principal and Independent Component Analysis 9.Testing with world seismicity of February 12, 2013 10. DPRK 2013 of February 12, 2013
Performance of waveform cross correlation using a global and regular grid of master events from Ivan Kitov
]]> 477 2 https://cdn.slidesharecdn.com/ss_thumbnails/rozhkovglobalgrid-131218124754-phpapp02-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 Modelling the transition from a socialist to capitalist economic system鐃 /slideshow/modelling-the-transition-from-a-socialist-to-capitalist-economic-system/28031271 eefs2005-131108020428-phpapp02
The transition from socialist economy to capitalsit economy modelled as a physical system]]>
The transition from socialist economy to capitalsit economy modelled as a physical system]]> Fri, 08 Nov 2013 02:04:28 GMT /slideshow/modelling-the-transition-from-a-socialist-to-capitalist-economic-system/28031271 IvanKitov@slideshare.net(IvanKitov) Modelling the transition from a socialist to capitalist economic system鐃 IvanKitov The transition from socialist economy to capitalsit economy modelled as a physical system <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/eefs2005-131108020428-phpapp02-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> The transition from socialist economy to capitalsit economy modelled as a physical system
Modelling the transition from a socialist to capitalist economic system from Ivan Kitov
]]> 1662 6 https://cdn.slidesharecdn.com/ss_thumbnails/eefs2005-131108020428-phpapp02-thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 Evolution of the personal income distribution in the USA: high incomes /slideshow/ecineq/28031217 ecineq-131108020145-phpapp01
Modelling personal incomes in the USA as a physical system]]>
Modelling personal incomes in the USA as a physical system]]> Fri, 08 Nov 2013 02:01:45 GMT /slideshow/ecineq/28031217 IvanKitov@slideshare.net(IvanKitov) Evolution of the personal income distribution in the USA: high incomes IvanKitov Modelling personal incomes in the USA as a physical system <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/ecineq-131108020145-phpapp01-thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> Modelling personal incomes in the USA as a physical system
Evolution of the personal income distribution in the USA: high incomes from Ivan Kitov
]]> 1604 4 https://cdn.slidesharecdn.com/ss_thumbnails/ecineq-131108020145-phpapp01-thumbnail.jpg?width=120&height=120&fit=bounds presentation White http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 Searching for aftershocks of underground explosions with cross correlation /slideshow/korea-2011/25953064 korea2011-130906060217-
We were looking for aftershocks after the 2009 DPRK announced test. Nothing was found.]]>
We were looking for aftershocks after the 2009 DPRK announced test. Nothing was found.]]> Fri, 06 Sep 2013 06:02:16 GMT /slideshow/korea-2011/25953064 IvanKitov@slideshare.net(IvanKitov) Searching for aftershocks of underground explosions with cross correlation IvanKitov We were looking for aftershocks after the 2009 DPRK announced test. Nothing was found. <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/korea2011-130906060217--thumbnail.jpg?width=120&amp;height=120&amp;fit=bounds" /><br> We were looking for aftershocks after the 2009 DPRK announced test. Nothing was found.
Searching for aftershocks of underground explosions with cross correlation from Ivan Kitov
]]> 423 4 https://cdn.slidesharecdn.com/ss_thumbnails/korea2011-130906060217--thumbnail.jpg?width=120&height=120&fit=bounds presentation Black http://activitystrea.ms/schema/1.0/post http://activitystrea.ms/schema/1.0/posted 0 https://cdn.slidesharecdn.com/profile-photo-IvanKitov-48x48.jpg?cb=1523571727 mechonomic.blogspot.co.at/ https://cdn.slidesharecdn.com/ss_thumbnails/spotcheck-180109103423-thumbnail.jpg?width=320&height=320&fit=bounds slideshow/assessing-the-consistency-quality-and-completeness-of-the-reviewed-event-bulletin-with-waveform-cross-correlation/85906335 Assessing the consiste... https://cdn.slidesharecdn.com/ss_thumbnails/mariupol-180109103054-thumbnail.jpg?width=320&height=320&fit=bounds IvanKitov/detection-and-location-of-small-aftershocks-using-waveform-cross-correlation Detection and location... https://cdn.slidesharecdn.com/ss_thumbnails/posterv3-180109102743-thumbnail.jpg?width=320&height=320&fit=bounds slideshow/waveform-cross-correlation-coherency-of-seismic-signals-estimated-from-repeated-mining-blasts/85905997 Waveform cross correla...