Over the past decade, earthquakes in Alberta have garnered broad scientific interest and public scrutiny.  A number of energy-related industry operations have been linked to earthquakes, most notably hydraulic fracturing, enhanced oil production, and wastewater disposal on the Duverney shale play. These event clusters necessitated critical changes to the existing Provincial regulations (Alberta Energy Regulator, 2015).

The latest, and most prominent, example of induced earthquakes in western Canada occurred on November 30, 2022, ~50 km away from the town of Peace River, Alberta. These earthquakes were broadly felt by residents throughout central Alberta.  Two earthquakes (with a maximum magnitude over 5.0) triggered hundreds of aftershocks that lasted for over a month. The two major earthquakes were initially deemed to be natural by Alberta Energy Regulator (AER, 2022), but a subsequent re-examination (by Ryan Schultz and coauthors) of disposed wastewater from in-situ oil recovery offered compelling evidence for their induced nature. To date, the November 30 Mw 5.2 earthquake is the largest known earthquake induced by human activities in Canada.  The nature of the Peace River earthquake swarm, the stability of subsurface faults, and their connections to the nearby disposal wells are critical issues for regional energy regulations and practices.   

The main objective of this proposal is two-fold: 1. to understand the root causes of Peace River seismicity, and 2. to provide practial models/recommendations to the oilsands operators for reduced seismic hazards.  To accomplish this we will combining data from recent nodal seismic deployment, geology, potential field (magnetism and gravity) and satelite imagery. We hope to address the following specific questions in connection with seismic mitigation in the Peace River area,

1. what role does each individual well (3 in total) affect the seismic sequence, both temporally and spatially?  Is there effect of triggering among the different earthquake clusters in this region?

2. do steam injections and other industrial operations near Peace River impact the subsurface conditions and fault criticality?

3. to what extent is the seismicity influenced by the geological history of the region, especially in connection with past episodes of crustal intrusions and coral reef development?

4. what practical models or recommendations could we provide to the day-to-day operations in Peace River area for oilsands recovery?

To address the above questions, our group aims to provide a new earthquake catalogue of earthquakes from 2022-2023. This catalogue will be the most accurate and complete, in comparison with other regional catalogues, due to the use of the nodal array deployed by the University and Alberta Geological Survey.  A short list of deliverables will include earthquake source solutions, slip and fault models, subsurface seismic velocities, attenuation structure and simulated ground motions.