|Title||Improved monitoring for seismic hazard assessment on British Columbia's north coast|
|Author||Brillon, C; Nykolaishen, L; Cassidy, J F|
|Source||Proceedings of the 11th National Conference in Earthquake Engineering; 2018 p. 1-14|
|Alt Series||Natural Resources Canada, Contribution Series 20180004|
|Publisher||Earthquake Engineering Research Institute|
|Meeting||Eleventh U.S. National Conference on Earthquake Engineering Integrating Science, Engineering & Policy; Los Angeles, CA; US; June 25-29, 2018|
|NTS||93D; 93E; 93L; 103A; 103B/09; 103B/10; 103B/15; 103B/16; 103G/01; 103G/02; 103G/07; 103G/08; 103G/09; 103G/10; 103G/15; 103G/16; 103H; 103I; 103J/01; 103J/02; 103J/07; 103J/08; 103J/09; 103J/10; 103J/15;
|Area||Prince Rupert; Kitimat; Bella Bella; Terrace; Haida Gwaii|
|Lat/Long WENS||-131.0000 -126.0000 55.0000 52.0000|
|Subjects||geophysics; tectonics; structural geology; surficial geology/geomorphology; seismology; seismic risk; earthquakes; earthquake risk; seismicity; earthquake magnitudes; tectonic setting; plate boundaries;
subduction zones; structural features; faults; shear zones; displacement; deformation; slope failures; seismographs; remote sensing; navigation satellites; glacial deposits; clays; seismic waves; s waves; strain analysis; North American Plate;
Pacific Plate; Explorer Plate; Juan de Fuca Plate; Cascadia Subduction Zone; Queen Charlotte Fault; Anahim Volcanic Belt; Grenville Channel Shear Zone; Coast Mountain Shear Zone; Principe-Laredo Shear Zone; 2012 MW 7.8 Haida Gwaii earthquake;
geological hazards; infrastructures; global navigation satellite systems (GNSS); monitoring; site response; global positioning systems (GPS); seismometers; glaciomarine sediments; frequency; amplification; microtremor surveys; horizontal-to-vertical
spectral ratio (HVSR); ground-motion intensity|
|Illustrations||location maps; tables; geoscientific sketch maps; spectra; time series|
|Program||Assessing Earthquake Geohazards, Public Safety Geoscience|
|Released||2018 07 01|
|Abstract||British Columbia's north coast (BCNC) is located 200 - 300 km east of the seismically active Pacific - North American plate boundary. It includes the port communities of Prince Rupert and Kitimat.
Historically, seismic and GNSS (Global Navigation Satellite System) monitoring and research has been limited in this region. Given the number of on-going and proposed infrastructure projects, Natural Resources Canada (NRCan) is conducting a 5-year
research program to gain a more detailed understanding of earthquake hazards in this area.|
Since July 2014 in the BCNC, NRCan has installed five real-time, co-located seismic and GNSS stations, three GNSS-only, and two seismic-only stations to
augment the existing monitoring networks. Since 2014, there have been over 300 earthquakes between magnitude (M) 0.5-3.7 located within the BCNC. There is no clustering of seismicity that highlights a previously unknown area of seismicity, is
associated with known faults, or corresponds to the recently mapped submarine slope failures. Displacements measured on GNSS stations indicate a broad area of the BCNC was, and remains, affected by the 2012 MW 7.8 Haida Gwaii earthquake.
addition, surveys were conducted to gain a better understanding of site response in the town of Kitimat. Analysis of horizontal-to-vertical spectral ratios recorded on soft-soil reveal a fundamental frequency between 1-2 Hz and amplification of 3-4
times. The regional seismograph and GNSS network, and site response study will contribute to an improved assessment of regional earthquake hazards.
|Summary||(Plain Language Summary, not published)|
Historically, geohazard research has been limited in British Columbia's north coast. Natural Resources Canada is conducting a 5-year research program to
gain a more detailed understanding of earthquake hazards in this area. To date NRCan has installed five, real-time, co-located seismic and GNSS stations, three GNSS-only, and two seismic-only stations. With these instruments over 300 earthquakes have
been located within the region, and displacements measured on GNSS stations indicate a broad area of the region remains affected by the 2012 MW 7.8 Haida Gwaii earthquake. Additional surveys revealed that shaking due to earthquakes could be
amplified by up to 4 times in areas of Kitimat.