Since December 2013, areas near Fox Creek, Alberta, Canada, have experienced increasing seismicity related to hydraulic fracturing activities in the Duvernay Formation. Most of these events are of small magnitude, and just a portion of the hydraulic fracturing activities are associated with induced seismicity. However, induced events related to the development of shale plays could generate increasing seismic hazard in areas with low natural seismic activity, leading to growing public awareness. In this study, we analyze the seismicity near Fox Creek to determine the annual likelihood of earthquakes greater than magnitude M larger than 4. We found that the seismic hazard near Fox Creek has declined since its peak in 2015, from a 95% probability of an earthquake greater than magnitude M larger than 4 in 2015 to 4% in 2019, and less than 1% probability in 2020. There are multiple reasons for this decrease in the seismic hazard, including the migration of activities toward areas less susceptible to induced seismicity and changes in the operational practices, at least partially in response to regulatory implementations in the area.

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