A southern Kansas earthquake felt as far north as Omaha is likely to add to the debate about the relationship between earthquakes and energy extraction.
Wednesday’s quake, with a magnitude of 4.8, was the strongest of the hundreds to have occurred in the Oklahoma area in the last 11 months, said Dale Grant, a geophysicist with the USGS. Oklahoma has seen a sharp jump in earthquakes with the explosive growth in well drilling commonly referred to as fracking. Kansas, too, has seen a jump. The location of this quake was just north of the Oklahoma-Kansas border.
“Oklahoma has become the new California,” Grant said. “We’ve recorded more magnitude 3 and greater earthquakes in Oklahoma in the last couple of years than we have in California, which is unprecedented.”
The earthquake occurred at 3:40 p.m. and by late afternoon , the USGS had received more than 4,500 reports across 11 states by people who had felt it. Among those were more than three-dozen reports from people in Omaha, Bellevue, Lincoln and Peru, Nebraska, and Council Bluffs and Glenwood, Iowa. The USGS encourages citizen reports via a “Did You Feel It?” website.
Despite the number of reports, no damage was known to have occurred, Grant said. That’s likely because the quake was considered light to moderate, he said.
The earthquake is believed to have occurred about 3.4 miles below ground and about eight miles south of Conway Springs, Kansas. It was one of about a half-dozen in that area Wednesday, according to the USGS.
Grant said that it’s too early to draw conclusions about this specific quake, but that scientists will be studying it.
The quake may have occurred along the Humboldt fault line, which runs from southeast Nebraska through Kansas and into north-central Oklahoma.
Grant said it’s not unusual for earthquakes to be felt at great distances in the central U.S. This part of the country is covered in more sedimentary layers than California, where granite is more common. Energy travels in higher amounts for longer distances through sedimentary rock, he said.
The latest science indicates the jump in earthquakes in Oklahoma is likely the result of wells that inject wastewater deep underground. Horizontally drilled oil and gas wells require huge amounts of water, and for now, energy companies are disposing of that water by injecting it deep underground.