USGS examines correlation between “fracking” and low-level earthquakes

Maybe not all earthquakes are “natural” disasters.

The U.S. Geological Survey (USGS) has issued a report suggesting “strong spatial and temporal correlations” existed between low-level earthquakes in Oklahoma in January 2011 and a nearby hydraulic fracturing project engaged in process known as “fracking.”

Fracking describes when large amounts of water and chemicals are injected underground at very high pressure to create fractures in underlying rock shale formations, thus allowing the extraction of natural gas.

The USGS reported that it received a phone call from a resident living south of Elmore City, in Garvin County, Oklahoma, who reported feeling several earthquakes throughout the night. The resident said an active hydraulic fracturing project was located nearby.

The USGS reported observing 50 earthquakes of a Magnitude of between 1.0 and 2.8 at around that time. The majority of the earthquakes occurred within 3.5 km of a well in the field where the hydraulic fracturing operation was taking place.

“The strong spatial and temporal correlations to the hydraulicfracturing in Picket Unit B Well 418 certainly suggest that the earthquakes observed in the Eola Field could have possibly been triggered by this activity,” the USGS said in its report, although it could not confirm a causal connection.

“While the societal impact of understanding whether or not small earthquakes may have been caused by hydraulicfracturing may be small, it could potentially help us learn more about subsurface properties such as stresses at depth, strength of faults, fluid flow, pressure diffusion, and long term fault and earthquake behaviors of the stable continent,” the report concluded. “It may also be possible to identify what criteria may affect the likelihood of anthropogenically induced earthquakes and provide oil and gas operators the ability to minimize any adverse affects.”