|Title||A brief history of Canada's earthquake hazard models and proposed update for the 2020 National Building Code|
Adams, J; Allen, T; Halchuk, S; Onur, T; Rogers, G|
|Source||Book of abstracts, 36th General Assembly of the European Seismological Commission; by D'Amico, S (ed.); Galea, P (ed.); Bozionelos, G (ed.); Colica, E (ed.); Farrugia, D (ed.); Agius, M R (ed.); 2018 p.
217-218 Open Access|
|Links||Online - En ligne (complete volume - volume
complet, PDF, 9.91 MB)|
|Alt Series||Natural Resources Canada, Contribution Series 20180061|
|Publisher||European Seismological Commission|
|Meeting||European Seismological Commission 36th General Assembly; Valletta; MT; September 2-7, 2018|
|File format||pdf (Adobe® Reader®)|
|Province||Canada; British Columbia; Alberta; Saskatchewan; Manitoba; Ontario; Quebec; New Brunswick; Nova Scotia; Prince Edward Island; Newfoundland and Labrador; Northwest Territories; Yukon; Nunavut;
|NTS||1; 2; 3; 10; 11; 12; 13; 14; 15; 16; 20; 21; 22; 23; 24; 25; 26; 27; 28; 29; 30; 31; 32; 33; 34; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 46; 47; 48; 49; 52; 53; 54; 55; 56; 57; 58; 59; 62; 63; 64; 65;
66; 67; 68; 69; 72; 73; 74; 75; 76; 77; 78; 79; 82; 83; 84; 85; 86; 87; 88; 89; 92; 93; 94; 95; 96; 97; 98; 99; 102; 103; 104; 105; 106; 107; 114O; 114P; 115; 116; 117; 120; 340; 560|
|Lat/Long WENS||-141.0000 -50.0000 90.0000 41.7500|
|Subjects||geophysics; surficial geology/geomorphology; Science and Technology; seismology; earthquakes; earthquake risk; seismic risk; seismicity; models; building codes; history; tectonic environments;
subduction; plate margins; downgoing slab; deformation; sediments; soils; earthquake catalogues; earthquake magnitudes; 2020 National Building Code of Canada; Cascadia Subduction Zone; Juan de Fuca Plate; Geographic information systems|
|Program||Public Safety Geoscience Assessing Earthquake Geohazards|
|Released||2018 09 01|
|Abstract||In this presentation, we outline the history of Canada's earthquake hazard models and summarise the key changes to the 2015 probabilistic model that are proposed for the 2020 National Building Code
(NBC) of Canada.|
Canada spans a variety of tectonic and geological settings, including an active plate boundary (with active subduction as well as divergent and transcurrent plate motions), a stable craton with the oldest rocks on earth, and an
ancient passive margin. As the second largest country in the world, and with such a variety of tectonic settings, creating a national hazard map is a challenging endeavour.
The earthquake hazard model that is utilised in the NBC is updated every
5 years (although not all updates are major). The first earthquake provisions in the NBCC were incorporated in 1953; beginning in 1970 a probabilistic seismic hazard model was adopted; the 1985 maps provided peak horizontal acceleration and peak
horizontal velocity; the 2005 model provided spectral parameters; and the most recent model (used in the 2015 NBCC) became a fully-probabilistic one, treating alternative source zones and Pacific margin subduction zone sources in a weighted logic
Anticipated changes to the 2020 model for seismic hazard include: updated rates for the Juan de Fuca subduction zone and a new geometry for inslab earthquake sources under Puget Sound; a more conventional use of alternative (and newer)
ground motion models in a weighted logic tree to replace the innovative Atkinson-Adams 2013 scaled-backbone approach. Furthermore, it is intended to replace the use of soil amplification factors applied to a single hazard map by direct calculation
of hazard for each soil class. We also note that for the first time, we have used the OpenQuake engine for development of the Canadian earthquake hazard model.
Ongoing questions and discussions include the adaptation and validation of GMPEs
developed with data from elsewhere around the world, the use of smoothed seismicity representations, declustering of the earthquake catalogue, minimum magnitude, and challenges associated with a short historical catalogue (especially for large
subduction earthquakes, and rare, large intraplate earthquakes), and incorporating GPS deformation rate data into hazard models. Many of these topics are also relevant for seismic hazard evaluations in Europe and elsewhere in the world.
|Summary||(Plain Language Summary, not published)|
This presentation outlines the history of earthquake hazard models used in the National Building Code of Canada (since 1954) and describes the new
methodologies and datasets that will be utilised in the earthquake hazard model for the 2020 National Building Code of Canada.