HR: 10:20h
AN: U32A-01 INVITED    [Abstracts]
TI: Global Seismic Monitoring: Past, Present, and Future
AU: * Zoback, M
EM: marylou.zoback@rms.com
AF: Risk Management Solutions, 7015 Gateway Blvd., Newark, CA 94560, United States
AU: Benz, H
EM: benz@usgs.gov
AF: U.S. Geological Survey, DFC Box 25046, MS 966, Denver, CO 80225, United States
AU: Oppenheimer, D
EM: oppen@usgs.gov
AF: U. S. Geological Survey, 345 Middlefield Rd., MS 977, Menlo Park, CA 94025, United States
AB: Global seismological observations began in April 1889 when an earthquake in Tokyo, Japan was accurately recorded in Germany on two different horizontal pendulum instruments. However, modern global observational seismology really began 46 years ago when the 120-station World Wide Standard Seismograph Network was installed by the US to monitor underground nuclear tests and earthquakes using well-calibrated short- and long- period stations. At the same time rapid advances in computing technology enabled researchers to begin sophisticated analysis of the increasing amount of seismic data, which led to better understanding of earthquake source properties and their use in establishing plate tectonics. Today, global seismic networks are operated by German (Geophon), France (Geoscope), the United States (Global Seismograph Network) and the International Monitoring System. Presently, the Federation of Digital Seismograph Networks registers more than 1,000 broadband stations world-wide, a small percentage of the total number of digital seismic stations around the world. Following the devastating Kobe, Japan and Northridge, California earthquakes, Japan and the US have led the world in the integration of existing seismic sensor systems (weak and strong motion) into development of near-real-time, post-earthquake response products like ShakeMap, detailing the spatial distribution of strong shaking. Future challenges include expanding real-time integration of both seismic and geodetic sensor systems to produce early warning of strong shaking, rapid source determination, as well as near-realtime post- earthquake damage assessment. Seismic network data, hydro-acoustic arrays, deep water tide gauges, and satellite imagery of wave propagation should be integrated in real-time to provide input for hydrodynamic modeling yielding the distribution, timing and size of tsunamis runup--which would then be available instantly on the web, e.g. in a Google Earth format. Dense arrays of strong motion sensors together with deployment of MEMS-type accelerometers in buildings and equipment routinely connected to the Web could potentially provide thousands of measurements of damaging strong ground motion. This technology could ultimately become part of smart building design enabling critical facilities to change their structural response to imminent strong shaking. Looking further forward, it is likely that a continuously observing spaceborne system could image the occurrence of "silent" or "slow" earthquakes as well as the propagation of ground displacement by surface waves at scales of continents.
DE: 7200 SEISMOLOGY
DE: 7212 Earthquake ground motions and engineering seismology
DE: 7219 Seismic monitoring and test-ban treaty verification
DE: 7294 Seismic instruments and networks (0935, 3025)
SC: Union [U]
MN: 2007 Fall Meeting