On Nov. 6, 2011, Oklahoma experienced its biggest earthquake ever, at level 5.6. I woke up to its boom 600 miles away in Denver.
An article in The Denver Post and a study reported by the scientific journal Geology (March 26, 2013) concluded that the likely cause of the quake was the accumulation of injected wastewater from oil and gas production in the area through hydraulic "tracking." In the county where the most quakes occurred, there were 181 "injection wells," and maps clearly showed a distinct correlation between the location of the swarm of earthquakes and these wells.
The United States Geological Services has studied "induced earthquakes," concluding that "Injected fluids can migrate substantial horizontal and vertical distances from the injection location." It states that injected wastewater "counteracts the frictional forces on faults and, in effect, 'pries them apart,' thereby facilitating earthquake slip."
Similar hydraulic fracking is now proposed in the Roscoe/Dean area (Oct. 24 Billings Gazette), as well as the Bearcreek area, approximately 80 miles from the edge of the Yellowstone caldera, our neighboring sleeping supervolcano.
Three super-eruptions of the volcano have occurred, a fourth believed by some, based on historical data, to be overdue. Yellowstone geophysicist Bob Smith has opined that if the volcano blew, "Devastation would be complete and incomprehensible," with the obliteration of Yellowstone Park, temperatures of hundreds of degrees, the spewing of ash thousands of times greater than Mount St. Helens' 1980 eruption, affecting worldwide agriculture indefinitely, and causing 87,000 immediate deaths.
Other scientists including Jacob Lowenstern of the Yellowstone Volcano Observatory have concurred.
Regarding the possibility of wastewater injections triggering a major earthquake, which could abruptly wake up our sleeping volcano, the USGS states "more research is needed to confirm or refute this possibility."
A complete study of the potential serious impacts of fracking this close to an active earthquake and volcanic area is absolutely necessary before further preliminary exploration or any of the dozens of planned wells become activated.