Induced seismicity refers to seismicity (earthquakes) caused by human activity. Induced seismicity is not limited to hydraulic fracturing operations. It is also associated with other industrial processes including geothermal energy extraction, wastewater disposal, mining, and hydroelectric dams.
Induced seismicity caused by hydraulic fracturing are small earthquakes that typically happen deep underground where the rock is being fractured. In rare instances, seismic events create anomalous vibrations that are felt on the surface. These are called anomalous induced seismicity or “felt events.” The vast majority of induced seismicity caused by hydraulic fracturing result in magnitudes of less than 1 ML as measured on the Richter scale and are not felt.
Hydraulic fracturing is a proven and highly regulated technique used to recover oil and natural gas from tight rock formations. It involves injecting fluids into deep rock formations at high enough pressures to create fractures in the rock. This opens pathways in the rock to allow oil and natural gas to flow. In rare instances, this process can trigger movement of an existing fault, leading to anomalous vibrations, some of which have been felt by residents in British Columbia and Alberta. Most induced seismicity related to oil and natural gas operations in Western Canada occurs where the rock is being fractured at depths of two to four km.
Scientific evidence, industry experience and regulator data indicate that impacts to structures, shallow aquifers or the environment from seismicity caused by hydraulic fracturing are very unlikely.
Hydraulic fracturing and induced seismicity are strictly regulated in B.C. and Alberta. Regulations are designed to protect people, structures and the environment, while allowing responsible development of oil and natural gas resources to continue.