Evaluation of Effectiveness in Seismic Microzonation Hazard Mapping in Canada: Communication, Use, Standardization and Levels
Abstract
Comprehensive seismic hazard maps in the form of seismic microzonation maps have been produced for many populous and seismically active Canadian cities. These maps are important tools for regional decision making for technical (engineering) and non-technical (planning, emergency management, insurance) applications. Outcomes from stakeholder engagement indicate that non-technical end users are not confident in their interpretation of the maps or the mapped site effect predictors (metrics). Users may seek seismic hazard information from lower-level mappings, such as the global Vs30 mosaic, which, when compared against the higher-level Canadian mappings, was found to correctly estimate site class with 26% accuracy and Vs30 values within ±49% of in situ measurements. Implementing best practices in cartographic design, using metrics consistent with building codes, distributing maps in digital formats, and co-developing products with end users are suggested to improve user comprehension and support effective utilization of higher-level Canadian seismic hazard products for regional applications.