Improving the monitoring and analysis of induced earthquakes

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Earthquakes come in all sizes, depths and magnitudes. The vast majority of them transpire along major plate boundaries, largely in response to tectonic forces. However, a growing number of intra-plate earthquakes in connection with industrial activities (also known as ‘induced earthquakes') are being reported at increasing frequencies and sizes. Some of these induced events are triggered by wastewater disposal, while others have been linked to multistage hydraulic fracturing operations on shale gas formation, most notably in the Western Canada Sedimentary Basin (WCSB).******In the next 5 years, my proposed research program will focus on the monitoring and analysis of seismicity in the WCSB. It will combine passive-source field deployments with laboratory-based analyses of seismicity, especially induced earthquakes in the past 5 years, in the WCSB. A temporary network of seismic receivers will be deployed in targeted areas, which will greatly increase the data coverage and potentially illuminate the subsurface faults in regions of active fluid injection. This effort will be complemented by a comprehensive laboratory program involving 1) real-time determination of critical source characteristics such as location, depth, magnitude and mechanism of induced earthquakes, 2) 3D simulations of ground motion, 3) integrated structural analyses of the sediment, crust and upper mantle, and 4) time-sensitive changes in fault slip and ground velocity. The outcomes of this proposal will shed new light on the subsurface faults and their criticality surrounding major injection operations. The timely determination of source parameters, history/rates and ground motions will be crucial for the understanding of the origin(s) of induced earthquakes. As has been the case in the past 6 years, our group will continue to work closely with the energy regulators and directly contribute to future regulations or policies on energy-related industrial practices.******I will be training 2 M.Sc. and 2 Ph.D. students, as well as 1 summer undergraduate research assistant each year. Research projects will be independent yet connected. The focus of my research program will form the nucleus for long-term studies of seismic risks in western Canada. This program will support the training of geoscientists specializing in critical aspects of field and quantitative geophysics. Nearly all students who completed their training in my research program in the past 6 years are currently holding permanent or semi-permanent positions at world-leading universities, energy regulatory agencies or major oil-gas exploration companies. Overall, my research program in the next 5 years will significantly improve our understanding of, and our ability to monitor, induced earthquakes in the WCSB. The outcomes could make a positive and direct impact on environmental and energy-related policies in the near future.