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- From: alden@netcom.com (Andrew L. Alden)
- Newsgroups: ca.earthquakes
- Subject: Real-time quake detection
- Message-ID: <1992Dec21.235536.12986@netcom.com>
- Date: 21 Dec 92 23:55:36 GMT
- Organization: Netcom - Online Communication Services (408 241-9760 guest)
- Lines: 45
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- Real-time earthquake warning systems are getting closer, as shown at the
- American Geophysical Union's meeting in San Francisco on December 10.
-
- After the October 1989 Loma Prieta quake, emergency workers at the fallen
- Cypress freeway structure in Oakland benefited from a jury-rigged
- aftershock detector; telemetry directly from the South Bay aftershock zone
- gave rescuers a few seconds' notice before seismic waves arrived. Since
- that time, efforts in northern and southern California have brought about
- widespread automated detection networks--and trained personnel to put their
- output to best use.
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- Egil Hauksson (Caltech) described progress in the Caltech - USGS Broadcast
- of Earthquakes, or CUBE, project which began in early 1991 and now includes
- eleven member agencies and utilities. The time, location, and magnitude of
- seismic events are broadcast to belt pagers and computers in near-real
- time, which "minimizes confusion and allows for immediate response of
- emergency management personnel," Hauksson said. The system affected
- responses in all three major southern California quakes in 1992. Now the
- project is tying in Terrascope, the state-of-the-art regional seismic
- array, to get faster and better magnitude estimates and to alert CUBE
- members of areas of strong ground motion. CUBE's long-term aim is to build
- a seismic computerized alert network, or SCAN, for the south state.
-
- The Berkeley Seismographic Station is doing similar work in the Bay area,
- upgrading its instruments, installing seismographs at new sites and tying
- in Stanford's seismic station. In June the station started work with USGS
- and UC Berkeley's Earthquake Engineering Research Center to share data in
- near real time and issue joint announcements within minutes of significant
- quakes in central and northern California, said Barbara Romanowicz.
-
- Pacific Gas & Electric Company has a telemetry prototype working that can
- sense seismic events and inform the central control room in San Francisco
- within 5 seconds. Using a display of the Bay area and its main electrical
- network that is updated every second, controllers can actually watch the
- shock spread as it trips alarms throughout the system--presumably while
- bellowing out warnings and orders. PG&E's Woody Savage showed a simulation
- of this setup, using the data from Loma Prieta, and it was quite a sight.
-
- Every second of warning can help utilities protect sensitive equipment,
- disconnect relays, back up computers, and start rerouting power. Emergency
- doors can be opened, response agencies can be alerted, and dispatchers can
- guide field technicians to where they're most needed.
-
- Copyright 1992, alden@netcom.com--please keep this notice with this story.
-