Date, time & venue
2017-02-22;6:30pm to 8:00pm;han Yat Mei Sophie Room, 9/F, HKIE HQ, Causeway Bay
The 2006 Sumatra-Andaman and 2011 Tohoku, Japan earthquakes were much larger than had been expected, and generated much larger tsunamis and much greater devastation than had ever been seen before. This has led to a re-evaluation of the tsunami potential around the world during the past twelve years.
The tsunami potential of earthquake source zones in the South China Sea has only recently received attention from seismologists following the occurrence of the tsunamis caused by the 2004 Sumatra-Andaman and 2011 Tohoku earthquakes, and requires further investigation. It is generally understood that the Manila Trench poses the most significant tsunami inundation threat to Hong Kong. The Manila Trench is the 1200-km long seafloor expression of a north-south trending, east-dipping subduction zone between the South China Sea oceanic crust (Eurasian plate) and the continental crust (Philippine plate) beneath Luzon Island, Philippines. The tectonic convergence rate across northern Luzon, i.e. the rate at which the South China Sea moves toward the Philippines, is on the order of 100 mm/yr and is among the highest observed anywhere. This points to a significant likelihood for a very large earthquake on this boundary, especially given the lack of large earthquakes in the last four centuries.
However, there is a large degree of uncertainty about the magnitude of the largest earthquake that this subduction zone source could generate, causing uncertainty in the heights of the tsunami that it could generate in Hong Kong. These estimates of maximum magnitudes range from 7.8 to 9.0, with corresponding tsunami wave heights in Hong Kong ranging from 1 to 8 meters. There is also a large degree of uncertainty in the frequency of occurrence of such events.
This presentation will illustrate how to reduce the current uncertainty in estimates of the seismic hazard level and the associated tsunami potential in Hong Kong by developing more reliable estimates and to use these estimates to identify potentially vulnerable locations.
Dr. Paul Somerville received his Ph.D. degrees in Geophysics at the University of British Columbia in Vancouver, Canada. He spent two years as a Visiting Research Fellow at the Earthquake Research Institute, University of Tokyo. Dr. Somerville has worked at AECOM and its predecessor organizations for the past 40 years. He is now managing the Seismology Group in Los Angeles. He has worked in many aspects of seismic hazards, and been involved in the development of innovative seismological methods for specifying seismic design ground motions in earthquake engineering practice. He has applied these in the design and analysis of major bridges, buildings, dams and power generation facilities in many countries, including Australia, New Zealand, the United States and Japan. Dr. Somerville has extensive research experience in Japan, where he pioneered the development of commonly used procedures for characterizing earthquake sources for the prediction of strong ground motion.
Free of charge
Registration & Enquiries
The number of participants is limited to 80 and priority will be given to members of Civil Division. Please complete the on-line registration at http://cv.hkie.org.hk. Email registration will not be accepted. Only successful applicants will be informed by email. For enquiries, please contact Ir Alex Li at email@example.com.
CPD certificate will be issued to those who attend the seminar.
Remarks: (The talk will be conducted in English)
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