© iStockphoto.com / cstar55QUAKE CAUSE?: Oklahoma recently experienced its strongest earthquake ever and some suggest drilling for oil and gas may have played a role.
The biggest earthquake ever recorded in Oklahoma struck on November 5, a magnitude 5.6 temblor that buckled a highway and ruptured water pipes. This quake is part of a skyrocketing rise in seismic activity the state has seen in the past three years, leading many to wonder - and worry - about its cause. Might the practice of fracking, a controversial method of drilling into rock for natural gas, be to blame?
The earthquake struck around 10 P.M. local time about 50 kilometers east of Oklahoma City, and was felt from Saint Louis to Dallas. Until then, the state's largest temblor was a magnitude 5.5 event near the town of El Reno in 1952.
Overall, only minor injuries and damage were reported after last weekend's earthquake. A magnitude 4.7 foreshock preceded the quake by about 20 hours, and dozens of aftershocks were detected as well. These all apparently happened on the well-mapped Wilzetta Fault. "It seems the east side of the fault moved a bit southward," says seismologist Randy Keller, director of the Oklahoma Geological Survey (OGS).
