Horses nuzzle near a seismometer deployed in a pasture near an earthquake epicenter in Sparks, Okla. A 5.6-magnitude earthquake shook near here in November 2011, the state's largest earthquake in a century.
Joe Wertz / StateImpact Oklahoma
Horses nuzzle near a seismometer deployed in a pasture near an earthquake epicenter in Sparks, Okla. A 5.6-magnitude earthquake shook near here in November 2011, the state's largest earthquake in a century.
Joe Wertz / StateImpact Oklahoma
More than 1,000 earthquakes were recorded in Oklahoma in 2010. The next year, there were more than 1,400 earthquakes, making 2011 the state’s most seismically active year on record.
A 5.6-magnitude quake was recorded that year — Oklahoma’s largest in at least a century — and researchers, regulators and the public are starting to ask questions about the state’s seismic risks.