Georgia Basin Amplification Factors for M9 Cascadia Earthquakes

This project quantifies long-period spectral acceleration amplification due to the Georgia sedimentary basin in Metro Vancouver.

Using a suite of 30 broadband simulations of M9 Cascadia Subduction Zone earthquakes, we benchmark ground motions against national models and derive period-dependent basin amplification factors (BAFs). These factors are validated using empirical data from the 2001 Nisqually earthquake and used to propose a framework for modifying Uniform Hazard Spectra (UHS) to better reflect the amplification effects.

The findings have implications for seismic hazard mapping, performance-based design, and future editions of the National Building Code of Canada.

📰 Related Publication

📖 Journal Article

• Spectral Acceleration Basin Amplification Factors for Interface Cascadia Subduction Zone Earthquakes in Canada’s 2020 National Seismic Hazard Model (Earthquake Spectra, 2023)
• Impacts of Simulated M9 Cascadia Subduction Zone Earthquakes Considering Amplifications due to the Georgia Sedimentary Basin on Reinforced Concrete Shear Wall Buildings (Earthquake Engineering & Structural Dynamics, 2021)

🎤 Conference Presentation

• Quantifying Basin Amplification in Southwest BC from Simulated M9 Cascadia Subduction Zone Earthquakes (17th World Conference on Earthquake Engineering, Sendai, Japan - 2020)
• Proposed basin amplification factors for subduction interface hazard in the 2020 seismic hazard model of Canada (12th US National Conference on Earthquake Engineering, Salt Lake City, US - 2022)

👥 Collaborators

• Carlos Molina Hutt
• Sai Mithra Dyaga
• Hadi Ghofrani
• Sheri Molnar