Title | Assessing the relative threats from Canadian volcanoes |
Download | Downloads |
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Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
Author | Wilson, A M; Kelman, M C |
Source | Geological Survey of Canada, Open File 8790, 2021, 65 pages, https://doi.org/10.4095/328950 Open Access |
Image |  |
Year | 2021 |
Publisher | Natural Resources Canada |
Document | open file |
Lang. | English |
Media | digital; on-line |
Related | NRCan photo(s) in this
publication |
File format | readme
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File format | pdf; rtf; docx (Microsoft® Word®); xlsx (Microsoft® Excel®) |
Province | British Columbia; Yukon |
NTS | 82; 83; 92; 93; 94; 95; 103; 104; 105; 115 |
Lat/Long WENS | -141.0000 -118.0000 64.0000 49.0000 |
Subjects | tectonics; geophysics; regional geology; surficial geology/geomorphology; Science and Technology; Nature and Environment; Health and Safety; Transport; volcanology; volcanic studies; volcanoes;
volcanism; seismic methods; lithofacies; satellite geodesy; deformation; landslides; in-field instrumentation; Garibaldi Volcanic Belt; Chilcotin Group; Anahim Volcanic Belt; Clearwater-Quesnel Volcanic Province; Northern Cordilleran Volcanic
Province; monitoring; Risk assessment; Methodology; Emergency preparedness; Emergency services; Aviation; Infrastructures; Phanerozoic; Cenozoic; Quaternary |
Illustrations | photographs; location maps; tables; geoscientific sketch maps; bar graphs |
Program | Public
Safety Geoscience Plate Boundary Earthquakes |
Released | 2021 10 14 |
Abstract | (unpublished) This report presents an analysis of the threat posed by active volcanoes in Canada and outlines directives to bring Canadian volcano monitoring and research into alignment with
global best practices. We analyse 28 Canadian volcanoes in terms of their relative threat to people, aviation and infrastructure. The methodology we apply to assess volcanic threat was developed by the United States Geological Survey (USGS) as part
of the 2005 National Volcano Early Warning System (NVEWS). Each volcano is scored on a number of hazard and exposure factors, producing an overall threat score. The overall threat scores are then assigned to five threat categories ranging from Very
Low to Very High. We adjusted the methodology slightly to better suit Canadian volcano conditions by adding an additional knowledge uncertainty score; this does not affect the threat scoring or ranking. Our threat assessment places two volcanoes into
the Very High threat category (Mt. Meager and Mt. Garibaldi). Three Canadian volcanoes score in the High threat category (Mt. Cayley, Mt. Price and Mt. Edziza) and two volcanoes score in the Moderate threat category (the Nass River group and Mt.
Silverthrone). We compare the ranked Canadian volcanoes to similarly scored volcanoes in the USA and assess the current levels of volcano monitoring against internationally recognised monitoring strategies. We find that even the most
thoroughly-studied volcano in Canada (Mt. Meager) falls significantly short of the recommended monitoring level (Mt. Meager is currently monitored at a level commensurate with a Very Low threat edifice, according to NVEWS recommendations). All other
Canadian volcanoes are unmonitored (other than falling within a regional seismic network emplaced to monitor tectonic earthquakes). Based on the relative threat and scientific uncertainty surrounding some Canadian volcanoes, we outline five
strategies to improve volcano monitoring in Canada and lower the uncertainty about eruption style and frequency: installation of real-time seismic stations at all Very High and High threat volcanoes, comprehensive lithofacies studies at Mt. Garibaldi
in order to reduce uncertainty surrounding the frequency and style of volcanism, hazard mapping at Mt. Garibaldi and Mt. Cayley and publication of existing hazard analyses and mapping for Mt. Meager as a comprehensive hazard map, regular
satellite-based ground deformation monitoring at all Very High to Moderate threat edifices, and, finally, installation of a landslide detection and alerting system at Mt. Meager. |
Summary | (Plain Language Summary, not published) We studied 28 Canadian volcanoes that may someday erupt again to learn which are the biggest threat to people or property. We gave each a score for
hazards (dangers like lava flows) and exposure (how close people and property are located), combined these into a total threat score, and put volcanoes into 5 groups ranging from Very Low to Very High threat. Our threat ranking shows two volcanoes as
Very High, three as High, and two as Moderate. We compared the amount of monitoring (watching for eruption warning signs) in Canada to recommended amounts. Canada doesn't have enough monitoring. We suggest 5 ways to improve monitoring and knowledge:
monitor Very High or High threat volcanoes for earthquakes, do detailed studies of Mt. Garibaldi, make hazard maps for Garibaldi, Cayley and Meager, do satellite monitoring for earth surface changes at Very High to Moderate threat volcanoes, and
ensure Mt. Meager has a system to quickly detect large landslides and alert areas at risk. |
GEOSCAN ID | 328950 |
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