Accession Number : ADP204492

Title :   Evaluation of the Performance of Broadband Networks and Short Period Arrays in Global Monitoring,

Corporate Author : CALIFORNIA UNIV BERKELEY SEISMOGRAPHIC STATION

Personal Author(s) : Dreger, Douglas ; Pasyanos, Michael ; Romanowicz, Barbara

PDF Url : ADP204492

Report Date : 14 AUG 1995

Pagination or Media Count : 8

Abstract : This study is a collaborative effort between the UC Berkeley Seismographic Station and the Lawrence Livermore National Laboratory to examine the performance of various seismographic systems in the regional monitoring of a Comprehensive Test Ban Treaty. Central California, with its abundant seismicity, regional broadband network (UCB BDSN), and dense short-period network (USGS NCSN) provides an ideal test-bed for the estimation of detection and location thresholds, source depth, and the seismic moment tensor of small events using sparse broadband network configurations. The objective is to investigate the importance of regional broadband stations in global monitoring. Together, the BDSN and NCSN networks provide the necessary data to construct a control catalog of very high quality event locations to a lower magnitude of approximately 1.8. We compare, against the control, catalogs obtained by inverting only BDSN data (both P only, and P and S waves), subsets of BDSN to test very sparse network configurations, as well as event detections and locations obtained from two regional short-period arrays located in Lajitas, TX and Pinedale, WY. In this manner we determine the detection and location threshold of each system and assess the resolving power of each. In particular, source depth resolution is investigated in the context of a traditional first motion location scheme, as well as the use of broadband waveforms recorded at regional distances. A component of this study will be the examination of path calibration to improve both source depth and seismic moment tensor determinations for small events recorded at regional distances. Improvements to the existing location algorithms will be examined to better constrain the BDSN and sparse network solutions.

Descriptors :   *DATA PROCESSING, *SEISMIC DETECTION, *SEISMIC WAVES, *ARMS CONTROL, *NUCLEAR EXPLOSION DETECTION, SYMPOSIA, MONITORING, UNDERGROUND EXPLOSIONS, NUCLEAR EXPLOSION TESTING, BROADBAND, CALIFORNIA, SEISMIC DISCRIMINATION, TREATIES, EARTHQUAKES, EPICENTERS, SEISMIC ARRAYS, SEISMOLOGICAL STATIONS, SECONDARY WAVES.

Subject Categories : Government and Political Science
      Seismology
      Seismic Detection and Detectors
      Nuclear Weapons
      Computer Programming and Software

Distribution Statement : APPROVED FOR PUBLIC RELEASE