Magnitude 4.7 earthquake shakes Oklahoma, Kansas

4 hours ago

TULSA, Okla. (Reuters) - A magnitude 4.7 earthquake struck northern Oklahoma early on Thursday, rattling residents out of their beds and shaking the ground across a 100-mile (161 km) radius that included the city of Tulsa and the state of Kansas.

The U.S. Geological Survey said the 1:42 a.m. CST quake's epicenter was 8 miles (13 km) southwest of Cherokee, Oklahoma.

With a shallow depth of 3.8 miles (6.2 km), it was one of the most-powerful temblors to shake Oklahoma since the strongest one recorded there struck in 2011 with a 5.6 magnitude.


There were no reports of any major damage or injuries, a Cherokee city hall official said. A local emergency management official said bridges did not appear to be damaged in areas around the quake's epicenter.


The frequency of quakes has increased markedly in Oklahoma since 2009 amid a boom in oil field work. Scientists have linked increased seismicity to the disposal of saltwater, a normal byproduct of oil and gas extraction work, into deep disposal wells and underground caverns.


"We’re getting used these earthquakes, although this was a big one," said Cherokee resident Stacey Siler. "Everyone just shot straight out of bed with this one."


Plenty of people reported feeling the earthquake in Wichita, Kansas, where there were no reported damages, said Van Williams, spokesman for the city. The area has felt numerous quakes in recent years but the one on Thursday may have been the most significant.


"It woke me up," Williams said. "I thought it was a bad dream. It felt like someone grabbed the house and shook it."


The quake comes about a month after an earthquake with a magnitude of 4.5 struck near the U.S. crude oil hub of Cushing, Oklahoma. That quake occurred just days after regulators imposed new rules to curb the use of saltwater disposal wells in a bid to prevent temblors in the area.


The Oklahoma Corporation Commission (OCC), which regulates the state's oil and gas industry, ordered companies on Sept. 18 to shut or reduce usage of a handful of saltwater disposal wells around the north-central Oklahoma city of Cushing.


It took additional measures after the quake and has introduced restrictions on disposal wells elsewhere in the state.

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