Oklahoma seeing surge in temblors
SPARKS, Okla. – Clouds of dust belched from the corners of almost every room in Joe Reneau’s house as the biggest earthquake in Oklahoma history rocked the two-story building.
A roar that sounded like a jumbo jet filled the air, and Reneau’s red-brick chimney collapsed and fell into the roof above the living room. By the time the shaking stopped, a pantry worth of food had been strewn across the kitchen and shards of glass and pottery covered the floor.
“It was like WHAM!” said Reneau, 75, gesturing with swipes of his arms. “I thought in my mind the house would stand, but then again, maybe not.”
The magnitude 5.6 earthquake and its aftershocks still had residents rattled Sunday.
Two minor injuries were reported from Saturday’s quakes by the Oklahoma Department of Emergency Management. And, aside from a buckled highway and the collapse of a tower on the St. Gregory’s University administration building in Shawnee, no major damage was reported.
But the weekend earthquakes were among the strongest yet in a state that has seen a dramatic, unexplained increase in seismic activity.
The earthquake was centered in Sparks, 44 miles northeast of Oklahoma City, and could be felt throughout the state and in Arkansas, Kansas, Missouri, northern Texas and some parts of Illinois and Wisconsin.
“We’ve been here 18 years, and it’s getting to be a regular occurrence,” said Jesse Richards, 50, of Sparks.
Geologists now believe a magnitude 4.7 earthquake Saturday morning was a foreshock to the bigger one that followed that night. They recorded at least 10 aftershocks by midmorning Sunday and expected more. Two of the aftershocks, at 4 a.m. and 9 a.m., were big, magnitude 4.0.
Scientists are puzzled by the recent seismic activity. It appeared the latest quake occurred on the Wilzetta fault, but researchers may never know for sure. Earthquakes that hit east of the Rocky Mountains are harder to pinpoint because the fault systems are not as well studied as major faults like the San Andreas in California.
Arkansas also has seen a big increase in earthquake activity, which residents have blamed on injection wells. Natural gas companies engaged in hydraulic fracturing, or fracking, use fluid to break apart shale and rock to release natural gas. Injection wells then dispose of the fluid by injecting it back into the ground.
There are 181 injection wells in the county where most of the weekend earthquakes happened, said Matt Skinner, spokesman for the Oklahoma Corporation Commission, which oversees oil and gas production in the state and intrastate transportation pipelines.
But natural gas companies claim there is no proof of a connection between injection wells and earthquakes, and a study released earlier this year by an Oklahoma Geological Survey seismologist seems to back that up. It found most of the state’s seismic activity didn’t appear to be tied to the wells.