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Seismic sensors and networks: Hawaii

Hawaii: volcanically and seismically activeActive subareal shield volcanoes: (1) Kilauea and (2) Mauna LoaActive fault systems in volcanic edifice and in lithosphereIn October 2006, M6.7 lithospheric earthquake (3) and aftershock sequence, caused widespread damage, including some to Mauna Kea telescope facilitiesThough not a problem in 2006, additional concern regarding locally-generated tsunamis associated with crustal earthquakes.

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Seismic sensors and networks: Hawaii

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    1. Seismic sensors and networks: Hawaii Earthquake Preparedness Workshop La Serena, Chile December, 2007 Paul Okubo, Geophysicist Hawaiian Volcano Observatory

    2. Earthquakes located by the USGS Hawaiian Volcano Observatory. Symbols are color-coded according to depth, sized to reflect magnitude. There are 5240 earthquakes on this map.Earthquakes located by the USGS Hawaiian Volcano Observatory. Symbols are color-coded according to depth, sized to reflect magnitude. There are 5240 earthquakes on this map.

    3. Seismic monitoring groups in Hawaii: US Geological Survey Hawaiian Volcano Observatory, National Strong Motion Project, and Global Seismographic Network; National Oceanic and Atmospheric Administration Pacific Tsunami Warning CenterSeismic monitoring groups in Hawaii: US Geological Survey Hawaiian Volcano Observatory, National Strong Motion Project, and Global Seismographic Network; National Oceanic and Atmospheric Administration Pacific Tsunami Warning Center

    4. Hawaiian Volcano Observatory (HVO): emphasis on volcano monitoring and using microearthquake information to infer magma location and transport Automatically detect and locate earthquakes, hypocenters available within minutes. Data analysts interactively review to produce final catalogs.Hawaiian Volcano Observatory (HVO): emphasis on volcano monitoring and using microearthquake information to infer magma location and transport Automatically detect and locate earthquakes, hypocenters available within minutes. Data analysts interactively review to produce final catalogs.

    5. Graph shows hypocenters projected onto plane parallel to Kilauea east rift zone, and plotted as a function of time between December 26, 1982 to January 9, 1983. Seismicity migrated clearly downrift, and HVO volcanologists actually saw the start of the eruption on January 3, positioning themselves on the basis of the earthquake locations.Graph shows hypocenters projected onto plane parallel to Kilauea east rift zone, and plotted as a function of time between December 26, 1982 to January 9, 1983. Seismicity migrated clearly downrift, and HVO volcanologists actually saw the start of the eruption on January 3, positioning themselves on the basis of the earthquake locations.

    6. USGS has operated accelerometers since 1973 to record large earthquakes in Hawaii for data that assists engineers. Historically, these recorded on film (SMA-1), but now these use digital technologies and can be telemetered. Operated along with broadband seismometers, greatly improved data are available and can be used in enhanced data analysis and data product generation. The earthquakes are simply recorded better.USGS has operated accelerometers since 1973 to record large earthquakes in Hawaii for data that assists engineers. Historically, these recorded on film (SMA-1), but now these use digital technologies and can be telemetered. Operated along with broadband seismometers, greatly improved data are available and can be used in enhanced data analysis and data product generation. The earthquakes are simply recorded better.

    7. Hawaii has a long record of large earthquakes. The written records extend to 1823. Instrumental recording began in 1912, so the graphs are separated at that point. Each line on the graph indicates the time of a M6 or larger earthquake. (Derrick Salmon willtalk about October 2006 earthquake a little bit.)Hawaii has a long record of large earthquakes. The written records extend to 1823. Instrumental recording began in 1912, so the graphs are separated at that point. Each line on the graph indicates the time of a M6 or larger earthquake. (Derrick Salmon willtalk about October 2006 earthquake a little bit.)

    8. Large historical Hawaiian earthquakes: black dots are crustal, depths to 15 km which is basically within or at the base of the volcanic edifice. Gray dots are lithospheric earthuqakes deeper than 15 km. More earthquakes beneath the active volcanoes.Large historical Hawaiian earthquakes: black dots are crustal, depths to 15 km which is basically within or at the base of the volcanic edifice. Gray dots are lithospheric earthuqakes deeper than 15 km. More earthquakes beneath the active volcanoes.

    9. Can describe future earthquake behaviors in terms of seismic hazards maps. HVO seismicity catalog, available USGS strong motion data are key elements that go into the seismic hazard modeling.Can describe future earthquake behaviors in terms of seismic hazards maps. HVO seismicity catalog, available USGS strong motion data are key elements that go into the seismic hazard modeling.

    10. The Pacific Tsunami Warning Center is concerned with tsunamis generated both teleseismically and locally. To help PTWC monitor large local earthquakes, HVO exports realtime seismic waveform data to PTWC.The Pacific Tsunami Warning Center is concerned with tsunamis generated both teleseismically and locally. To help PTWC monitor large local earthquakes, HVO exports realtime seismic waveform data to PTWC.

    11. Tsunami wave transit times from locally generated earthquakes is very short. Rapid earthquake processing and notification is very important. Tsunami travel time from west coast of Hawaii to Honolulu is approximately 20 minutes. Tsunami wave transit times from locally generated earthquakes is very short. Rapid earthquake processing and notification is very important. Tsunami travel time from west coast of Hawaii to Honolulu is approximately 20 minutes.

    12. In addition to October 2006 Hawaii earthquakes, 2004 Sumatran earthquake and Indian Ocean tsunami brought increased focus on seismic monitoring in Hawaii. The result is an opportunity to upgrade and modernize.In addition to October 2006 Hawaii earthquakes, 2004 Sumatran earthquake and Indian Ocean tsunami brought increased focus on seismic monitoring in Hawaii. The result is an opportunity to upgrade and modernize.

    13. It will be important to achieve the upgrades effectively and without unnecessary duplication of effort. USGS and NOAA have agreed to the principle of coordinated seismic network operations while adhering to Bureau-specific requirements and missions. We have begun to develop and implement the idea of a Hawaii Integrated Seismic Network to accomplich these goals.It will be important to achieve the upgrades effectively and without unnecessary duplication of effort. USGS and NOAA have agreed to the principle of coordinated seismic network operations while adhering to Bureau-specific requirements and missions. We have begun to develop and implement the idea of a Hawaii Integrated Seismic Network to accomplich these goals.

    14. The HISN will extend across the entire State of Hawaii to provide authoritative reporting capability on earthquakes occurring in the region. The HISN will extend across the entire State of Hawaii to provide authoritative reporting capability on earthquakes occurring in the region.

    15. The HISN will operate as a part of the USGS Advanced National Seismic System project. The ANSS is built on partnerships among the USGS andother seismic monitoring interests across the US. Performance of the HISN, as well as the ANSS in general, is tied to the ability to generate and disseminate reliable earthquake information products developed and supported by the ANSS. USGS support to do this is available, but individual networks also retain the ability to develop their own capabilities, especially if other funding sources impose different Requirements or provide alternatives.The HISN will operate as a part of the USGS Advanced National Seismic System project. The ANSS is built on partnerships among the USGS andother seismic monitoring interests across the US. Performance of the HISN, as well as the ANSS in general, is tied to the ability to generate and disseminate reliable earthquake information products developed and supported by the ANSS. USGS support to do this is available, but individual networks also retain the ability to develop their own capabilities, especially if other funding sources impose different Requirements or provide alternatives.

    17. Based on data. Earliest recognition of earthquake = P-wave first arrival at closest station. Strong shaking/potential for damage? Use the arrival of the S-waves.Based on data. Earliest recognition of earthquake = P-wave first arrival at closest station. Strong shaking/potential for damage? Use the arrival of the S-waves.

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