Federal study: Oklahoma more at risk of big damaging quakes because of increase in small ones

FILE - In this Nov. 6, 2011 file photo, Chad Devereaux examines bricks that fell from three sides of his in-laws home in Sparks, Okla., after two earthquakes hit the area in less than 24 hours. New federal research says small earthquakes shaking Oklahoma and southern Kansas daily are dramatically increasing the chance of bigger and dangerous quakes, new federal research indicates. (AP Photo/Sue Ogrocki, File) (The Associated Press)

File - In this Nov. 6, 2011 file photo, maintenance workers inspect the damage to one of the spires on Benedictine Hall at St. Gregory's University in Shawnee, Okla., after two earthquakes hit the area in less than 24 hours. New federal research says small earthquakes shaking Oklahoma and southern Kansas daily are dramatically increasing the chance of bigger and dangerous quakes, new federal research indicates. (AP Photo/Sue Ogrocki) (The Associated Press)

New federal research says small earthquakes shaking Oklahoma and southern Kansas daily are dramatically increasing the chance of bigger and dangerous quakes.

Scientists link many of these quakes to the deep underground injections of wastewater after drilling for energy in a process known as hydraulic fracturing, or fracking.

Federal records show Oklahoma has had nearly 200 quakes that people have felt since Jan. 1.

U.S. Geological Survey geophysicist William Ellsworth says the jump in these nuisance quakes increases the risk of future ones that can do serious damage.

The number of small quakes started rising in 2008 and then really soared in 2013 and 2014.

Ellsworth says it's still a low risk, with a chance of about 1 in 2,500 years, but it's among the highest east of the Rockies.