Tuesday’s 5.8 tremor occurred in an area where wastewater is injected underground, building pressure over time.
The oil and gas industry operates oil wells in the region and there are numerous well pads near the epicentre of the quake. Around 50,000 of 700,000 oil and gas wells drilled in Alberta are used to dispose of waste or produced water.
I was doing some work around Peace River a couple of years ago. I took this picture on the way to a service call. It’s a beautiful area.
The Alberta Energy Regulator did acknowledge wastewater disposal wells in the area. “While there are fluid disposal operations in the region, none are in the immediate vicinity of the seismic events, nor have there been changes in the rates of fluid disposal over the past year,” the AER wrote in an email to The Tyee.
The regulator made no mention that fluid injection can unpredictably cause tremors tens of kilometres away from the triggering drill site. Or that earthquakes can occur kilometres below the injection site. Texas studies show that even shallow waste water disposal can cause deep earthquakes.
Water injection as a byproduct of drilling for oil and gas has generated tremors measuring 5.0 or higher in Oklahoma and other oil and gas regions such as British Columbia.
Earthquakes ranging from magnitudes of 5.0 to 5.9 are readily felt and can cause damage to buildings. Earthquakes 6.0 and up can damage even structures made to be earthquake proof.
In the 1980 and 1990s water injection to recover oil in the Eagle West field started a swarm of quakes around Fort St. John, B.C., which until then had been classified as a low seismic area.
The record breaking Alberta quakes follow a similar swarm of tremors caused by a fracking operation in northern B.C. just three weeks ago.
Expert calls for ‘detailed investigation and review’
