POLARIS: AN IN-DEPTH LOOK AT CANADA'S SUBCONTINENTAL MANTLE AND EARTHQUAKE HAZARDS

Presented by Atkinson, Gail
Authors:
      Jones, Alan G.,
      Bostock, Michael,
      Eaton, David E.,
      Ferguson, Ian J.,
      Thomson, Colin,
      Adams, John,
      Asudeh, Isa,
      Cassidy, John,
      Snyder, David.

Key words: earthquakes, seismicity, lithosphere, seismology, magnetotellurics

In Session 207     T18. Earthscope--A Look into Our Continent: Opportunities for Interdisciplinary Research in Geophysics and Geology (GSA Geophysics Division; Nevada Seismological Laboratory) Thursday, November 16, 2000 AM in Room: Ballroom B at 08:45 AM for 15 min .

Abstract: POLARIS (Portable Observatories for Lithospheric Analysis and Research Investigating Seismicity) is a multi-institutional $10M program recently funded by the Canadia n Foundation for Innovation for the creation of a network of portable, satellite-linked geophysical observatories in Canada. This program brings together scientists in universities, governments, and the private sector in an innovative research project dedicated to interdisciplinary studies of subcontinental mantle architecture and earthquake ground motions (and related hazards) in the northern half of the North American continent. The major components of POLARIS are a network of 90 three-component broadband seismometers, 30 magnetotelluric (MT) field systems, complementary data acquisition and satellite communications equipment, and three satellite downlink facilities. Over the initial four-year start-up phase the seismograph network will be deployed as three arrays of 30 instruments. The MT equipment will be used in shorter-term deployments at each of the seismometer sites for crustal and lithospheric imaging, and continuous recording at selected locations for both deep-mantle imaging and for monitoring any time-varying conductivity structure accompanying earthquakes. An array deployed in NWT and Nunavut territories will be used to investigate lithospheric roots and asthenospheric mantle underlying the Slave craton in Canada's north. The second array will investigate the seismic hazard to southern Ontario, and the third array will map the structure and earthquake hazards over the Cascadia subduction zone in southwest British Columbia. POLARIS will be the first mobile geophysical facility in the world to exploit satellite communications technology for data acquisition. This new geophysical infrastructure will enable ground-breaking research in combined applications of collocated teleseismic and magnetotelluric arrays for lithospheric analysis. Data collected by this system will be available in real-time over the Internet, and will be permanently archived by the Geological Survey of Canada.