Earthquake safety for Kansas teachers and students
A strong earthquake in northern Oklahoma just across the Kansas border shook a wide area of the Midwest, including Wichita and surrounding communities on Friday afternoon.
The 4.4 magnitude earthquake struck about 3:30 p.m. with an epicenter about 9 miles southeast of Medford, or about 23 miles northeast of Enid, the U.S. Geological Survey reported. According to preliminary data, the quake struck about 3 miles deep.
“This was a pretty strong one,” said seismologist Paul Caruso of the USGS. “It was probably felt by a lot of people.”
The USGS asks people who felt the quake to report it online. An intensity map shows many reports from Tulsa, Oklahoma City, Wichita and other towns across the two states. Further away reports include ones from near Denver, Lincoln Kansas City, St. Louis, Cincinnati, Little Rock, Atlanta, Baton Rouge, Houston, Corpus Christi and Mason City, Iowa.
“Not hearing about any damage,” Wichita Police Chief Gordon Ramsay said in a tweet. “It rumbled pretty good though.”
Oklahoma and Kansas had practically no noteworthy seismic activity until about 10 years ago, but have experienced hundreds of earthquakes since.
The temblors are linked to the underground disposal of oil field waste brought on by a boom in hydraulic fracturing, or “fracking.” Fracking is the practice of injecting high pressure fluid underground to break up rock formations and free trapped petroleum and natural gas.
Experts say that the fracking itself doesn’t cause quakes like the one Wichita felt Friday.
What causes the quakes is the disposal of waste water that comes up with the oil — about 16 barrels of water for every barrel of oil recovered.
That water is too salty and oil-polluted to be disposed of at the surface, so it’s injected back into rock formations deep underground. In some cases, that water disrupts the balance of forces in the deep rock causing movement and earthquakes.