The big picture in western Canada: Induced seismicity from geo-energy applications is approaching the natural moment release rate of tectonically active northern regions

The Western Canada Sedimentary Basin (WCSB) covers a vast area, extending from a zero edge along the Canadian Shield to the Canadian Cordillera in the west, where the basin is up to 7 km thick. Seismicity is largely concentrated within a ≈300km wide corridor, immediately east of the deformation front of the Canadian Cordillera. The northern half of the WCSB experiences natural earthquakes in the Mackenzie and Richardson Mountains, which are strongly influenced by plate-boundary interactions along the west coast of North America. To the south, seismicity in northeastern BC and western Alberta is characterized by localized induced (human-caused) seismic activity related to unconventional resource development during the last 15 years. This north-south partitioning of seismicity is reflected in Canada’s national seismic hazard maps, which consider only natural seismic hazards and highlight areas of relatively elevated seismic hazard in the Mackenzie and Richardson Mountains. However, since 2021 the seismic moment-release rates have become broadly similar in both southern and northern regions of the WCSB, despite relative seismic quiescence in the south from 2000 – 2014. Short-term seismic hazard maps for Alberta show localized areas of elevated seismic hazard that track temporarily and spatially varying levels of industry activity. The advent of large-scale carbon capture and storage (CCS) and geothermal projects could increase the potential for anthropogenic triggering of seismic activity.