Seismic crustal structure beneath the BC convergent margin

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The interface between the underthrust oceanic plate and over-riding continental plate is currently locked and accumulating energy which will be released in a future great earthquake similar to the magnitude 9 event in 1700. However, we do not know whether the earthquake will rupture the seafloor and contribute to tsunami generation. At present, there is a lack of information as basic as whether there are even any small earthquakes in the region offshore Vancouver Island. Such information is critical to provide the scientific basis for informing the public of earthquake, tsunami and seafloor-landslide hazards, and may help prevent the potential loss of life. In collaboration with researchers at the Geological Survey of Canada and seismologists at the Japan Agency for Marine-Earth Science & Technology (JAMSTEC), I deployed 33 ocean bottom seismometers (OBSs) from JAMSTEC for a 3-month period in summer 2010. As well, 10 broadband OBSs from Woods Hole Oceanographic Institution (currently deployed for 1-year period) plus 2 near-real-time NEPTUNE-Canada broadband instruments form part of our grid. Phase 2 of the project is planned in 2012, with ~35 Japanese OBSs to be deployed in a more focused study. We anticipate that these deployments will allow us to detect earthquakes at an unprecedented sensitivity. The broadband instruments will also allow us to record "Very Low Frequency Earthquakes", slow-slip events often associated with low-amplitude seismic tremor.