GEOSCAN Search Results: Fastlink


TitleSeismic hazard investigations at select DND facilities in Southwestern British Columbia: subduction, in-slab, and crustal scenarios
LicencePlease note the adoption of the Open Government Licence - Canada supersedes any previous licences.
AuthorPaul, C; Cassidy, J FORCID logo
SourceGeological Survey of Canada, Open File 8934, 2022, 35 pages, Open Access logo Open Access
PublisherNatural Resources Canada
Documentopen file
Mediadigital; on-line
File formatreadme
File formatpdf; rtf; docx
ProvinceBritish Columbia
NTS92B; 92C; 92E; 92F; 92G
AreaSouthwestern British Columbia
Lat/Long WENS-128.0000 -122.0000 51.0000 48.0000
SubjectsGovernment and Politics; Health and Safety; tectonics; seismic risk; seismic zones; seismology; subduction; earthquake risk; earthquake studies; earthquakes; modelling; Cascadia Subduction Zone; Natural hazards; Assessment; Risk assessment
Illustrationslocation maps; seismic cross-sections; plots; tables; spectra
ProgramPublic Safety Geoscience Assessing Earthquake Geohazards
Released2022 12 22
AbstractSouthwest British Columbia has some of the highest seismic hazard in Canada and is home to facilities owned by the Department of National Defence which support operations on the west coast of Canada. The potential impact of seismic hazards on these government facilities are investigated here. The hazard is from three primary sources: subduction interface, crustal and in-slab earthquakes. NRCan, in consultation with DRDC have produced representative earthquake scenarios for each of these sources. The subduction scenario we constructed was an M8.9 earthquake extending along the entire Cascadia Subduction Zone from 4 to 18 km depth. We used an M6.8 earthquake occurring along a 30 km fault at between 52 and 60 km depth below Boundary Bay to represent in-slab events. The final scenario, representing a crustal source, was an M6.4 along the central 47 km of the Leech River Valley-Devil's Mountain Fault system. We found that the Cascadia subduction scenario dominated the shaking hazard over much of the study region. Meanwhile, the in-slab and crustal scenarios have higher but more localized hazards in Vancouver and Victoria. In addition to the primary ground motion hazard, we also examined secondary seismic hazards: secondary amplification effects, landslides, liquefaction, surface ruptures, tsunami, flooding, fire, and aftershocks. Each of the secondary hazards had varying impacts depending on the scenario and locations within the region.
Summary(Plain Language Summary, not published)
This publication develops and outlines three earthquake scenarios for southwest British Columbia that serve as the input for seismic risk scenarios for select DND bases in the area (to be published as a companion article). This work covers the three primary types of earthquakes in this region - a shallow, crustal earthquake, a deep earthquake in the subducting oceanic plate, and a major (offshore) subduction earthquake. In addition to the direct hazard, secondary hazards such as liquefaction, landslides, amplification, tsunami, and aftershocks are discussed.

Date modified: