IAG-IASPEI 2017

講演情報

Poster

IASPEI Symposia » S07. Strong ground motions and Earthquake hazard and risk

[S07-P] Poster

2017年8月2日(水) 15:30 〜 16:30 Event Hall (The KOBE Chamber of Commerce and Industry, 2F)

15:30 〜 16:30

[S07-P-17] Multi-use seismic stations for earthquake early warning

Bruce Townsend, Stephen Kilty, Geoffrey Bainbridge, David Easton, Tim Parker (Nanometrics Seismic Monitoring Solutions, Ottawa, Canada)

Earthquake Early Warning (EEW) network performance improves with the number and density of sensing stations, quality of the sites and of strong-motion instrumentation, degree of coverage near at-risk populated areas and potential fault zones, and minimizing latency of signal processing and transmission. Seismic research tends to emphasize competing requirements: low-noise sites, high-performance broadband seismic instrumentation, and high-quality signal processing without regard for latency. Recent advances in instrumentation and processing techniques have made feasible the concept of a multi-use seismic station in which strong- and weak-motion seismometry are both cost-effectively served without compromising the performance demands of either.
Our concept for a multi-use seismic station meets the needs of both EEW and high-quality seismic research. One significant enabler is a 6-channel dual-sensor instrument that combines a 120s broadband seismometer and a class A accelerometer in a single ultra-compact sonde suitable for direct burial. Combining two sensors effectively adds broadband capability to a station without increasing the already optimized site footprint, preparation and management costs associated with shallow direct-burial installations. The combined sensors also simplify and speed up installation (for example, the accelerometer provides real-time tilt readings useful to leveling the seismometer). Integration simplifies alignment to north, as there is only one instrument to orient. A dual-use 6-channel digitizer simultaneously provides two sets of independently processed streams from both sensors, one set optimized for low-latency earthquake warning, and the other set for high-quality seismic research purposes.
Such a dual-use seismic station can serve both seismic research and civil warning infrastructure objectives without adding significantly to the cost of a single-use station, while increasing the utility for all users of the station's data.