Single station sigma data set from subduction earthquakes Nick Gregor November 30 th , 2011 LTSP SSHAC Level 3 Update – Workshop 1
Single station sigma data set from subduction earthquakes
Nick Gregor November 30th, 2011
LTSP SSHAC Level 3 Update – Workshop 1
Subduction Earthquake Dataset
• BC Hydro SSHAC Level 3 Study
• Interface events
• Intraslab events
• Estimated Vs30m for site conditions
Subduction Earthquake Dataset Composite Data Sources: • Crouse (1988, 1991)
• Youngs et al. (1997)
• Atkinson and Boore (2003/2008)
• Zhao et al. (2006/2008)
• Cheng (2008) [Taiwan]
• Pacific Engineering and Analysis (2008) [South and Central America]
• Carrasco (2008) [Mexico]
Subduction Earthquake Dataset • 292 subduction earthquakes
– 163 Interface events (3,557 horizontal pairs) – 129 Intraslab events (6,389 horizontal pairs)
• Exclude M<6 (interface), M<5 (intraslab) – ~4,000 intraslab/2,000 interface recordings – 90% of database from Japan and Taiwan
• Interface Dataset: – Magnitudes = 6.5 -8.4 – Distances = 5 – 551 km
• Intraslab Dataset: – Magnitudes = 5.0 – 7.9 – Distances = 34 – 991 km
Subduction Earthquake Dataset
Recent Earthquakes not currently included: • 2010 Maule Chile (Mw8.8)
– 26 stations – Distance = 34-200km – Vs30m = 236-1,421m/s
• 2011 Tohoku Japan (Mw9.0) – 369 stations (K-Net, Kik-Net) – Distance = 44-989 km – Vs30m = 107-1,433 m/s
Single Station Dataset • Stations with 5 or more recordings
Region Number of Recordings
Number of Stations
Japan 56 14
Mexico 16 3
Taiwan 867 126