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Proceedings of the 2010 Monitoring Research Review: Ground-Based Nuclear Explosion Monitoring Technologies

Description: These proceedings contain papers prepared for the Monitoring Research Review 2010: Ground-Based Nuclear Explosion Monitoring Technologies, held 21-23 September, 2010 in Orlando, Florida,. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Air Force Research Laboratory (AFRL), US Army Space and Missile Defense Command, National Science Foundation (NSF), Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), and other invited sponsors. The scientific objectives of the research are to improve the United States capability to detect, locate, and identify nuclear explosions. The purpose of the meeting is to provide the sponsoring agencies, as well as potential users, an opportunity to review research accomplished during the preceding year and to discuss areas of investigation for the coming year. For the researchers, it provides a forum for the exchange of scientific information toward achieving program goals, and an opportunity to discuss results and future plans. Paper topics include: seismic regionalization and calibration; detection and location of sources; wave propagation from source to receiver; the nature of seismic sources, including mining practices; hydroacoustic, infrasound, and radionuclide methods; on-site inspection; and data processing.
Date: September 21, 2010
Creator: Wetovsky, Marvin A. & Patterson, Eileen F.
Partner: UNT Libraries Government Documents Department

Proceedings of the 2011 Monitoring Research Review: Ground-Based Nuclear Explosion Monitoring Technologies

Description: These proceedings contain papers prepared for the Monitoring Research Review 2011: Ground-Based Nuclear Explosion Monitoring Technologies, held 13-15 September, 2011 in Tucson, Arizona. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Defense Threat Reduction Agency (DTRA), Air Force Research Laboratory (AFRL), US Army Space and Missile Defense Command, Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), National Science Foundation (NSF), and other invited sponsors. The scientific objectives of the research are to improve the United States' capability to detect, locate, and identify nuclear explosions. The purpose of the meeting is to provide the sponsoring agencies, as well as potential users, an opportunity to review research accomplished during the preceding year and to discuss areas of investigation for the coming year. For the researchers, it provides a forum for the exchange of scientific information toward achieving program goals, and an opportunity to discuss results and future plans. Paper topics include: seismic regionalization and calibration; detection and location of sources; wave propagation from source to receiver; the nature of seismic sources, including mining practices; hydroacoustic, infrasound, and radionuclide methods; on-site inspection; and data processing.
Date: September 13, 2011
Creator: Wetovsky, Marvin A.; Patterson, Eileen F. & Sandoval, Marisa N.
Partner: UNT Libraries Government Documents Department

Proceedings of the 23rd Seismic Research Symposium: Worldwide Monitoring of Nuclear Explosions

Description: These proceedings contain papers prepared for the 23rd Seismic Research Review: Worldwide Monitoring of Nuclear Explosions, held 2-5 October, 2001 in Jackson Hole, Wyoming. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Defense Threat Reduction Agency (DTRA), Air Force Technical Applications Center (AFTAC), the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), and other invited sponsors. The scientific objectives of the research are to improve the United States capability to detect, locate, and identify nuclear explosions. The purpose of the meeting is to provide the sponsoring agencies, as well as potential users, an opportunity to review research accomplished during the preceding year and to discuss areas of investigation for the coming year. For the researchers, it provides a forum for the exchange of scientific information toward achieving program goals, and an opportunity to discuss results and future plans. Paper topics include: seismic regionalization and calibration; detection and location of sources; wave propagation from source to receiver; the nature of seismic sources, including mining practices; hydroacoustic, infrasound, and radionuclide methods; on-site inspection; and data processing.
Date: October 2, 2001
Creator: Warren, N. Jill & Chavez, Francesca C.
Partner: UNT Libraries Government Documents Department

Proceedings of the 21st Seismic Research Symposium: Technologies for Monitoring The Comprehensive Nuclear Test-Ban Treaty

Description: These proceedings contain papers prepared for the 21st Seismic Research Symposium: Technologies for Monitoring The Comprehensive Nuclear-Test-Ban Treaty, held 21-24 September 1999 in Las Vegas, Nevada. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Defense Threat Reduction Agency (DTRA), Air Force Technical Applications Center (AFTAC), Department of Defense (DoD), the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), and other invited sponsors. The scientific objectives of the research are to improve the United States capability to detect, locate, and identify nuclear explosions. The purpose of the meeting is to provide the sponsoring agencies, as well as potential users, an opportunity to review research accomplished during the preceding year and to discuss areas of investigation for the coming year. For the researchers, it provides a forum for the exchange of scientific information toward achieving program goals, and an opportunity to discuss results and future plans. Paper topics include: seismic regionalization and calibration; detection and location of sources; wave propagation from source to receiver; the nature of seismic sources, including mining practices; hydroacoustic, infrasound, and radionuclide methods; on-site inspection; and data processing.
Date: September 21, 1999
Creator: Warren, N. Jill
Partner: UNT Libraries Government Documents Department

Proceedings of the 24th Seismic Research Review: Nuclear Explosion Monitoring: Innovation and Integration

Description: These proceedings contain papers prepared for the 24th Seismic Research Review: Nuclear Explosion Monitoring: Innovation and Integration, held 17-19 September, 2002 in Ponte Vedra Beach, Florida. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Defense Threat Reduction Agency (DTRA), and other invited sponsors. The scientific objectives of the research are to improve the United States capability to detect, locate, and identify nuclear explosions. The purpose of the meeting is to provide the sponsoring agencies, as well as potential users, an opportunity to review research accomplished during the preceding year and to discuss areas of investigation for the coming year. For the researchers, it provides a forum for the exchange of scientific information toward achieving program goals, and an opportunity to discuss results and future plans. Paper topics include: seismic regionalization and calibration; detection and location of sources; wave propagation from source to receiver; the nature of seismic sources, including mining practices; hydroacoustic, infrasound, and radionuclide methods; on-site inspection; and data processing.
Date: September 17, 2002
Creator: Warren, N. Jill
Partner: UNT Libraries Government Documents Department

Proceedings of the 25th Seismic Research Review -- Nuclear Explosion Monitoring: Building the Knowledge Base

Description: These proceedings contain papers prepared for the 25th Seismic Research Review -- Nuclear Explosion Monitoring: Building the Knowledge Base, held 23-25 September, 2003 in Tucson, Arizona. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Defense Threat Reduction Agency (DTRA), Air Force Research Laboratory (AFRL), US Army Space and Missile Defense Command, and other invited sponsors. The scientific objectives of the research are to improve the United States capability to detect, locate, and identify nuclear explosions. The purpose of the meeting is to provide the sponsoring agencies, as well as potential users, an opportunity to review research accomplished during the preceding year and to discuss areas of investigation for the coming year. For the researchers, it provides a forum for the exchange of scientific information toward achieving program goals, and an opportunity to discuss results and future plans. Paper topics include: seismic regionalization and calibration; detection and location of sources; wave propagation from source to receiver; the nature of seismic sources, including mining practices; hydroacoustic, infrasound, and radionuclide methods; on-site inspection; and data processing.
Date: September 23, 2003
Creator: Chavez, Francesca C. & Mendius, E. Louise
Partner: UNT Libraries Government Documents Department

Proceedings of the 26th Seismic Research Review: Trends in Nuclear Explosion Monitoring

Description: These proceedings contain papers prepared for the 26th Seismic Research Review: Trends in Nuclear Explosion Monitoring, held 21-23 September, 2004 in Orlando, Florida. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Defense Threat Reduction Agency (DTRA), Air Force Research Laboratory (AFRL), US Army Space and Missile Defense Command, and other invited sponsors. The scientific objectives of the research are to improve the United States capability to detect, locate, and identify nuclear explosions. The purpose of the meeting is to provide the sponsoring agencies, as well as potential users, an opportunity to review research accomplished during the preceding year and to discuss areas of investigation for the coming year. For the researchers, it provides a forum for the exchange of scientific information toward achieving program goals, and an opportunity to discuss results and future plans. Paper topics include: seismic regionalization and calibration; detection and location of sources; wave propagation from source to receiver; the nature of seismic sources, including mining practices; hydroacoustic, infrasound, and radionuclide methods; on-site inspection; and data processing.
Date: September 21, 2004
Creator: Chavez, Francesca C.; Benson, Jody; Hanson, Stephanie; Mark, Carol & Wetovsky, Marvin A.
Partner: UNT Libraries Government Documents Department

Proceedings of the 27th Seismic Research Review: Ground-Based Nuclear Explosion Monitoring Technologies

Description: These proceedings contain papers prepared for the 27th Seismic Research Review: Ground-Based Nuclear Explosion Monitoring Technologies, held 20-22 September, 2005 in Rancho Mirage, California. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Air Force Technical Applications Center (AFTAC), Air Force Research Laboratory (AFRL), US Army Space and Missile Defense Command, and other invited sponsors. The scientific objectives of the research are to improve the United States capability to detect, locate, and identify nuclear explosions. The purpose of the meeting is to provide the sponsoring agencies, as well as potential users, an opportunity to review research accomplished during the preceding year and to discuss areas of investigation for the coming year. For the researchers, it provides a forum for the exchange of scientific information toward achieving program goals, and an opportunity to discuss results and future plans. Paper topics include: seismic regionalization and calibration; detection and location of sources; wave propagation from source to receiver; the nature of seismic sources, including mining practices; hydroacoustic, infrasound, and radionuclide methods; on-site inspection; and data processing.
Date: September 20, 2005
Creator: Wetovsky, Marvin A.; Benson, Jody & Patterson, Eileen F.
Partner: UNT Libraries Government Documents Department

Proceedings of the 28th Seismic Research Review: Ground-Based Nuclear Explosion Monitoring Technologies

Description: These proceedings contain papers prepared for the 28th Seismic Research Review: Ground-Based Nuclear Explosion Monitoring Technologies, held 19-21 September, 2006 in Orlando, Florida. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Air Force Technical Applications Center (AFTAC), Air Force Research Laboratory (AFRL), US Army Space and Missile Defense Command, Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), and other invited sponsors. The scientific objectives of the research are to improve the United States capability to detect, locate, and identify nuclear explosions. The purpose of the meeting is to provide the sponsoring agencies, as well as potential users, an opportunity to review research accomplished during the preceding year and to discuss areas of investigation for the coming year. For the researchers, it provides a forum for the exchange of scientific information toward achieving program goals, and an opportunity to discuss results and future plans. Paper topics include: seismic regionalization and calibration; detection and location of sources; wave propagation from source to receiver; the nature of seismic sources, including mining practices; hydroacoustic, infrasound, and radionuclide methods; on-site inspection; and data processing.
Date: September 19, 2006
Creator: Wetovsky, Marvin A.; Benson, Jody & Patterson, Eileen F.
Partner: UNT Libraries Government Documents Department

Proceedings of the 29th Monitoring Research Review: Ground-Based Nuclear Explosion Monitoring Technologies

Description: These proceedings contain papers prepared for the 29th Monitoring Research Review: Ground-Based Nuclear Explosion Monitoring Technologies, held 25-27 September, 2007 in Denver, Colorado. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Air Force Technical Applications Center (AFTAC), Air Force Research Laboratory (AFRL), US Army Space and Missile Defense Command, Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), and other invited sponsors. The scientific objectives of the research are to improve the United States capability to detect, locate, and identify nuclear explosions. The purpose of the meeting is to provide the sponsoring agencies, as well as potential users, an opportunity to review research accomplished during the preceding year and to discuss areas of investigation for the coming year. For the researchers, it provides a forum for the exchange of scientific information toward achieving program goals, and an opportunity to discuss results and future plans. Paper topics include: seismic regionalization and calibration; detection and location of sources; wave propagation from source to receiver; the nature of seismic sources, including mining practices; hydroacoustic, infrasound, and radionuclide methods; on-site inspection; and data processing.
Date: September 25, 2007
Creator: Wetovsky, Marvin A.; Benson, Jody & Patterson, Eileen F.
Partner: UNT Libraries Government Documents Department

Proceedings of the 22nd Annual DoD/DOE Seismic Research Symposium: Planning for Verification of and Compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT)

Description: These proceedings contain papers prepared for the 22nd Annual DoD/DOE Seismic Research Symposium: Planning for Verification of and Compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT), held 13-15 September 2000 in New Orleans, Louisiana. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Defense Threat Reduction Agency (DTRA), Air Force Technical Applications Center (AFTAC), Department of Defense (DoD), US Army Space and Missile Defense Command, Defense Special Weapons Agency (DSWA), and other invited sponsors. The scientific objectives of the research are to improve the United States capability to detect, locate, and identify nuclear explosions. The purpose of the meeting is to provide the sponsoring agencies, as well as potential users, an opportunity to review research accomplished during the preceding year and to discuss areas of investigation for the coming year. For the researchers, it provides a forum for the exchange of scientific information toward achieving program goals, and an opportunity to discuss results and future plans. Paper topics include: seismic regionalization and calibration; detection and location of sources; wave propagation from source to receiver; the nature of seismic sources, including mining practices; hydroacoustic, infrasound, and radionuclide methods; on-site inspection; and data processing.
Date: September 15, 2000
Creator: Nichols, James W., LTC
Partner: UNT Libraries Government Documents Department

Proceedings of the 30th Monitoring Research Review: Ground-Based Nuclear Explosion Monitoring

Description: These proceedings contain papers prepared for the 30th Monitoring Research Review: Ground-Based Nuclear Explosion Monitoring Technologies, held 23-25 September, 2008 in Portsmouth, Virginia. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Air Force Technical Applications Center (AFTAC), Air Force Research Laboratory (AFRL), US Army Space and Missile Defense Command, Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), and other invited sponsors. The scientific objectives of the research are to improve the United States’ capability to detect, locate, and identify nuclear explosions. The purpose of the meeting is to provide the sponsoring agencies, as well as potential users, an opportunity to review research accomplished during the preceding year and to discuss areas of investigation for the coming year. For the researchers, it provides a forum for the exchange of scientific information toward achieving program goals, and an opportunity to discuss results and future plans. Paper topics include: seismic regionalization and calibration; detection and location of sources; wave propagation from source to receiver; the nature of seismic sources, including mining practices; hydroacoustic, infrasound, and radionuclide methods; on-site inspection; and data processing.
Date: September 23, 2008
Creator: Wetovsky, Marv A; Aguilar-chang, Julio; Arrowsmith, Marie; Arrowsmith, Stephen; Baker, Diane; Begnaud, Michael et al.
Partner: UNT Libraries Government Documents Department

Superresolution with Seismic Arrays using Empirical Matched Field Processing

Description: Scattering and refraction of seismic waves can be exploited with empirical matched field processing of array observations to distinguish sources separated by much less than the classical resolution limit. To describe this effect, we use the term 'superresolution', a term widely used in the optics and signal processing literature to denote systems that break the diffraction limit. We illustrate superresolution with Pn signals recorded by the ARCES array in northern Norway, using them to identify the origins with 98.2% accuracy of 549 explosions conducted by closely-spaced mines in northwest Russia. The mines are observed at 340-410 kilometers range and are separated by as little as 3 kilometers. When viewed from ARCES many are separated by just tenths of a degree in azimuth. This classification performance results from an adaptation to transient seismic signals of techniques developed in underwater acoustics for localization of continuous sound sources. Matched field processing is a potential competitor to frequency-wavenumber and waveform correlation methods currently used for event detection, classification and location. It operates by capturing the spatial structure of wavefields incident from a particular source in a series of narrow frequency bands. In the rich seismic scattering environment, closely-spaced sources far from the observing array nonetheless produce distinct wavefield amplitude and phase patterns across the small array aperture. With observations of repeating events, these patterns can be calibrated over a wide band of frequencies (e.g. 2.5-12.5 Hertz) for use in a power estimation technique similar to frequency-wavenumber analysis. The calibrations enable coherent processing at high frequencies at which wavefields normally are considered incoherent under a plane wave model.
Date: March 24, 2010
Creator: Harris, D B & Kvaerna, T
Partner: UNT Libraries Government Documents Department

Integrated modeling and field study of potential mechanisms forinduced seismicity at The Geysers Goethermal Field, California

Description: In this paper, we present progress made in a study aimed atincreasing the understanding of the relative contributions of differentmechanisms that may be causing the seismicity occurring at The Geysersgeothermal field, California. The approach we take is to integrate: (1)coupled reservoir geomechanical numerical modeling, (2) data fromrecently upgraded and expanded NCPA/Calpine/LBNL seismic arrays, and (3)tens of years of archival InSAR data from monthly satellite passes. Wehave conducted a coupled reservoir geomechanical analysis to studypotential mechanisms induced by steam production. Our simulation resultscorroborate co-locations of hypocenter field observations of inducedseismicity and their correlation with steam production as reported in theliterature. Seismic and InSAR data are being collected and processed foruse in constraining the coupled reservoir geomechanicalmodel.
Date: June 7, 2006
Creator: Rutqvist, Jonny; Majer, Ernie; Oldenburg, Curt; Peterson, John & Vasco, Don
Partner: UNT Libraries Government Documents Department

Louisiana Gulf Coast seismicity induced by geopressured-geothermal well development

Description: Continuous microseismic monitoring networks have been established around three US Department of Energy geopressured-geothermal design wells in southwestern Louisiana since summer 1980 to assess the effects well development may have on subsidence and growth fault activation. The results obtained from this monitoring have shown several unusual characteristics associated with Gulf Coast seismic activity. The observed activity is classified into two dominant types, one with identifiable body phases and the other with only surface wave signatures. The latter type comprises over 99% of the reported 1000+ microseismic event locations. The problem with the slow-moving surface-wave signature events is that rainfall and weather-associated frontal passages seem closely related to these periods of seismic activity at all three wells. After relatively short periods and low levels of flow testing at the Parcperdue and Sweet Lake prospects, seismic monitoring has shown little credible correlation to inferred growth fault locations during periods of flow testing. Longer periods and higher volumes of flow testing at the Rockefeller Refuge prospect should provide a truer indication of induced seismicity attributable to geopressured-geothermal development. 4 refs., 5 figs.
Date: January 1, 1985
Creator: Stevenson, D.
Partner: UNT Libraries Government Documents Department

Building on and spinning off: Sandia National Labs` creation of sensors for Vietnam

Description: This paper discusses Sandia National Laboratories` development of new technologies for use in the Vietnam War - specifically the seismic sensors deployed to detect troop and vehicle movement - first along the Ho Chi Minh Trail and later in perimeter defense for American military encampments in South Vietnam. Although the sensor story is a small one, it is interesting because it dovetails nicely with our understanding of the war in Vietnam and its frustrations; of the creation of new technologies for war and American enthusiasm for that technology; and of a technological military and the organizational research and a m am development structure created to support it. Within the defense establishment, the sensors were proposed within the context of a larger concept - that of a barrier to prevent the infiltration of troops and supplies from North Vietnam to the South. All of the discussion of the best way to fight in Vietnam is couched in the perception that this was a different kind of war than America was used to fighting. The emphasis was on countering the problems posed by guerrilla/revolutionary warfare and eventually by the apparent constraints of being involved in a military action, not an outright war. The American response was to find the right technology to do the job - to control the war by applying a technological tincture to its wounds and to make the war familiar and fightable on American terms. And, when doubts were raised about the effectiveness of applying existing technologies (namely, the bombing of North Vietnam and Laos), the doubters turned to new technologies. The sensors that were developed for use in Vietnam were a direct product of this sort of thinking - on the part of the engineers at Sandia who created the sensors, the civilian scientific advisors who recommended ...
Date: December 31, 1996
Creator: Ullrich, R.
Partner: UNT Libraries Government Documents Department

Infrasonic signals from an accidental chemical explosion

Description: A series of large accidental explosions occurred at a chemical plant in Henderson, Nevada on May 4, 1988. The explosions were produced by the ignition of stores of ammonium perchlorate produced for solid rocket fuel at the Pacific Engineering and Production Co. This material, prior to the incident, had been believed to be non- explosive. The blasts destroyed the plant and caused one death. There was a series of explosions over a period of time with two major explosions which we will identify as A at 18:53:34 (all times herein will be given in C.U.T.) and B at 18:57:35. Signals from events A and B as well as smaller events were detected by the infrasound arrays operated by the Los Alamos National Laboratory at St. George, Utah (distance 159 km) and at Los Alamos, N.M. (distance 774 km). The Henderson explosions present an interesting and challenging set of infrasound observations. The case may be unique in providing two very large sources separated in time by only four minutes. To fully understand the propagation details will require further analysis and probably a modeling effort. The understanding of the St. George signals in the context of Lamb waves would be valuable for a better understanding of this mode of propagation. The improved understanding of long range infrasonic propagation is now especially important in the context of the Comprehensive Test Ban Treaty (CTBT). A portion of the plan for CTBT monitoring includes a global distribution of sixty infrasound arrays to provide for the monitoring of signals in as uniform a way as possible. It is expected that under this global network many signals and interpretation questions of the type described here will be encountered. Investigations of propagation over the ranges of hundreds to thousands of kilometers will be highly desired.
Date: December 31, 1996
Creator: Mutschlecner, J.P. & Whitaker, R.W.
Partner: UNT Libraries Government Documents Department

Regional observations of mining blasts by the GSETT-3 seismic monitoring system

Description: The cessation of testing of any nuclear explosive devices in all environments is the goal of the Comprehensive Test Ban Treaty. In order to assure compliance with such a treaty, an international monitoring system has been proposed. This system will include seismic, infrasound, hydroacoustic and radionuclide monitors located throughout the world. The goal of this system is the detection of any nuclear test. In preparation for this treaty, a series of monitoring system tests, focusing primarily on seismic observations, have been undertaken. The most recent of these tests, Group of Scientific Experts Technical Test Three (GSETT-3), provides valuable data for assessing future monitoring systems. During the course of this experiment, seismic events associated with earthquakes, nuclear explosions and mining explosions have been recorded. This presentation will discuss the numbers and types of mining explosions triggering the system, in a particular area. Possible implications for the mining industry will be explored.
Date: December 31, 1996
Creator: Stump, B.W. & Pearson, D.C.
Partner: UNT Libraries Government Documents Department

Infrasound workshop for CTBT monitoring: Proceedings

Description: It is expected that the establishment of new infrasound stations in the global IMS network by the Provisional Technical Secretariat of the CTBTO in Vienna will commence in the middle of 1998. Thus, decisions on the final operational design for IMS infrasound stations will have to be made within the next 12 months. Though many of the basic design problems have been resolved, it is clear that further work needs to be carried out during the coming year to ensure that IMS infrasound stations will operate with maximum capability in accord with the specifications determined during the May 1997 PrepCom Meeting. Some of the papers presented at the Workshop suggest that it may be difficult to design a four-element infrasound array station that will reliably detect and locate infrasound signals at all frequencies in the specified range from 0.02 to 4.0 Hz in all noise environments. Hence, if the basic design of an infrasound array is restricted to four array elements, the final optimized design may be suited only to the detection and location of signals in a more limited pass-band. Several participants have also noted that the reliable discrimination of infrasound signals could be quite difficult if the detection system leads to signal distortion. Thus, it has been emphasized that the detection system should not, if possible, compromise signal fidelity. This report contains the workshop agenda, a list of participants, and abstracts and viewgraphs from each presentation.
Date: November 1, 1998
Creator: Christie, D. & Whitaker, R.
Partner: UNT Libraries Government Documents Department

Testing the waveform correlation event detection system: Teleseismic, regional, and local distances

Description: Waveform Correlation Event Detection System (WCEDS) prototypes have now been developed for both global and regional networks and the authors have extensively tested them to assess the potential usefulness of this technology for CTBT (Comprehensive Test Ban Treaty) monitoring. In this paper they present the results of tests on data sets from the IDC (International Data Center) Primary Network and the New Mexico Tech Seismic Network. The data sets span a variety of event types and noise conditions. The results are encouraging at both scales but show particular promise for regional networks. The global system was developed at Sandia Labs and has been tested on data from the IDC Primary Network. The authors have found that for this network the system does not perform at acceptable levels for either detection or location unless directional information (azimuth and slowness) is used. By incorporating directional information, however, both areas can be improved substantially suggesting that WCEDS may be able to offer a global detection capability which could complement that provided by the GA (Global Association) system in use at the IDC and USNDC (United States National Data Center). The local version of WCEDS (LWCEDS) has been developed and tested at New Mexico Tech using data from the New Mexico Tech Seismic Network (NMTSN). Results indicate that the WCEDS technology works well at this scale, despite the fact that the present implementation of LWCEDS does not use directional information. The NMTSN data set is a good test bed for the development of LWCEDS because of a typically large number of observed local phases and near network-wide recording of most local and regional events. Detection levels approach those of trained analysts, and locations are within 3 km of manually determined locations for local events.
Date: August 1, 1997
Creator: Young, C.J.; Beiriger, J.I. & Harris, J.M.
Partner: UNT Libraries Government Documents Department

Regional characterization of Western China-II

Description: As part of the CTBT Research and Development regional characterization effort, geological, geophysical, and seismic data are being assembled and organized for inclusion in a knowledge base for China. The authors have continued their analysis using data form the station WMQ of the Chinese Digital Seismic Network (CDSN) and the IRIS station AAK. They are also acquiring and analyzing data from stations that are designated as (or near a designated) primary or secondary CTBT monitoring station. Regional seismograms are being analyzed to construct travel time curves, velocity models, attenuation characteristics, and to quantify regional propagation effects such as phase blockages. Using locations from the USGS Preliminary Determination of Epicenters (PDE) they have identified Pn, Pg, Sn, and Lg phases, constructed travel time curves, and estimated apparent velocities using linear regression. Amplitudes for the seismic phases have been measured using bandpassed waveforms and a series of magnitude relations have been determined for Western China. Studies of path specific propagation efficiency of the seismic phases have mapped blockages and also identified a possible set of observations that can be used to identify intermediate depth (> 100 im) seismic events in the Pamir-Hindu Kush seismic zone. Chinese seismicity catalogs from the USGS and Chinese State Seismological Bureau (SSB) are being used to identify and obtain seismic data (including mine seismicity) and information for lower magnitude events. Clustering analysis has been used to identify seismicity clusters in space with origin times that are distributed during daylight hours which suggest mining operations. These clusters are being investigated with imagery to attempt to identify precise mine locations.
Date: October 1, 1996
Creator: Randall, G.E.; Hartse, H.E.; Phillips, W.S. & Taylor, S.R.
Partner: UNT Libraries Government Documents Department

Mining industry and US government cooperative research: Lessons learned and benefits to mining industry

Description: Since 1994, various mines in the US have cooperated with research scientists at the Los Alamos and Lawrence Livermore National Laboratories to address issues related to verification of the Comprehensive Test Ban Treaty (CTBT). The CTBT requires that no country may conduct any nuclear explosion in the future. While the CTBT is a significant step toward reducing the global nuclear danger, verifying compliance with the treat requires that the monitoring system be able to detect, locate and identify much larger numbers of smaller amplitude seismic events than had been required previously. Large mining blasts conducted world-wide will be of sufficient amplitude to trigger the monitoring system at the lower threshold. It is therefore imperative that research into the range various blasting practices employed, the relationship of yield to seismic magnitude, and identification of anomalous blasting results be performed. This paper will describe a suite of experiments funded by the Department of Energy and conducted by the Los Alamos and Lawrence Livermore National Laboratories in cooperation with the US mining industry. Observations of cast blasting, underground long wall generated coal bumps, stoping, and explosively induced collapse of room and pillar panels will be presented. Results of these dual use experiments which are of interest to the mining community will be discussed. These include (1) variation of amplitude of seismic energy at various azimuths from cast blasts, (2) identification of the extent of back failure following explosive removal of pillars, and (3) the use of single fired shots for calibration of the monitoring system. The wealth of information and discovery described in this paper is a direct result of mutual cooperation between the US Government and the US Mining Industry.
Date: September 1, 1997
Creator: Pearson, D.C.; Stump, B.W.; Phillips, W.S.; Martin, R. & Anderson, D.P.
Partner: UNT Libraries Government Documents Department

The source depth of burial experiment at Shagan River, Kazakstan

Description: The seismic field experimentation team at Los Alamos National Laboratory collaborated with Lawrence Livermore, the Defense Special Weapons Agency (DSWA) and the National Nuclear Center of the Republic of Kazakstan to record the Source Depth of Burial Experiment during the summer of 1997. A series of three 25 ton explosions at depths of 50, 300 and 550 meters along with associated 50 to 100 kg Green`s function explosions and a 5 ton proof of concept explosion were instrumented at near source (0.1 to 20 km) and regional distances (100 to 1,100 km) using portable seismic data acquisition equipment. The near source data represent the first US recordings of seismic data at the former Soviet Union`s Semipalatinsk nuclear test site. The main objective of the Depth of Burial Experiment was to test whether source depth can help identify underground nuclear explosions from observations at distance ranges of 100--1,000 km. A secondary objective was to help calibrate the Kazakstan seismic network, especially the primary IMS station at Makanchi and the auxiliary IMS stations at Kurchatov and Aktyubinsk. Near-source records show the 50 m deep explosion generated much higher amplitude surface (R{sub g}) waves than did either of the deeper explosions. Impulse P-wave arrivals dominated the traces from the 300 and 550 meter deep explosions. P-wave amplitudes, 10--20 Hz, appeared to be a stronger function of source than of path or site. Apparent P velocity was highly path dependent, with higher velocities parallel to the local, NW-SE fabric of the geologic structure. Empirical Green`s function results for the 25 ton shots show increasing corner frequency with depth, consistent with predictions of the Mueller-Murphy source model.
Date: December 31, 1998
Creator: Pearson, D.C.; Phillips, W.S.; Glenn, L.A. & Denny, M.D.
Partner: UNT Libraries Government Documents Department