HR: 1400h
AN: S23A-08 [Abstracts]
TI: High-Performance Tools: Nevada's Experiences Growing Network Capability
AU: * Biasi, G
EM: glenn@seismo.unr.edu
AF: Nevada Seismological Laboratory, University of Nevada Reno
MS-174, Reno, NV 89557, United States
AU: Smith, K D
EM: ken@seismo.unr.edu
AU: Slater, D
EM: dslater@seismo.unr.edu
AU: Preston, L
EM: preston@seismo.unr.edu
AF: Nevada Seismological Laboratory, University of Nevada Reno
MS-174, Reno, NV 89557, United States
AU: Tibuleac, I
EM: ileana@seismo.unr.edu
AF: Nevada Seismological Laboratory, University of Nevada Reno
MS-174, Reno, NV 89557, United States
AB:
Like most regional seismic networks, the Nevada Seismic Network relies on a combination of software
components to perform its mission. Core components for automatic network operation are from Antelope, a real-
time environmental monitoring software system from Boulder Real-Time Technologies (BRTT). We configured
the detector for multiple filtering bands, generally to distinguish local, regional, and teleseismic phases. The
associator can use all or a subset of detections for each location grid. Presently we use detailed grids in the
Reno-Carson City, Las Vegas, and Yucca Mountain areas, a large regional grid and a teleseismic grid, with a
configurable order of precedence among solutions. Incorporating USArray stations into the network was straight-
forward. Locations for local events are available in 30-60 seconds, and relocations are computed every 20
seconds. Testing indicates that relocations could be computed every few seconds or less if desired on a modest
Sun server. Successive locations may be kept in the database, or criteria applied to select a single preferred
location. New code developed by BRTT partially in response to an NSL request automatically launches a
gradient-based relocator to refine locations and depths. Locations are forwarded to QDDS and other notification
mechanisms. We also use Antelope tools for earthquake picking and analysis and for database viewing and
maintenance.
We have found the programming interfaces supplied with Antelope instrumental as we work toward ANSS system
performance requirements. For example, the Perl language interface to the real-time Object Ring Buffer (ORB)
was used to reduce the time to produce ShakeMaps to the present value of ~3 minutes. Hypoinverse was
incorporated into a real-time system with Perl ORB access tools. Using the Antelope PHP interface, we now have
off-site review capabilities for events and ShakeMaps from hand-held internet devices. PHP and Perl tools were
used to develop a remote capability, now nearly operational, by which technicians in the field can trigger a
calibration pulse and signal to pulse analysis software at UNR. Station status similar to the Array Network Facility
at UCSD has been implemented in PHP. Network analysts are using Antelope Matlab access methods to
estimate focal mechanisms selectably from first motions and/or P/S amplitude ratios. The db2xml Antelope
extension allows us to export any database table or view directly to XML. This capability will underlie XML data
and parametric information exchange. Because ORB and database access tools are available in high-level
languages all of the above could be done without resort to compilers or compiled languages. This is perhaps
most important for improving network performance in the long run because more of the staff can contribute to
network development.
DE: 7219 Seismic monitoring and test-ban treaty verification
DE: 7294 Seismic instruments and networks (0935, 3025)
SC: Seismology [S]
MN: 2007 Joint Assembly