The Ohio Department of Natural Resources today ordered a drilling company to temporarily halt operations in Mahoning County, in the wake of two small earthquakes.
The order affects Hilcorp Energy that has been drilling horizontal wells in Poland Township. It has drilled a dozen wells in the area.
The two quakes were centered near Lowellville on the Ohio-Pennsylvania line and were about 1.2 miles deep, according to the U.S. Geological Survey.
The first quakes occurred about 2:26 a.m. and measured 2.8 magnitude. It was later upgraded to 3.0 magnitude.
It was reportedly under the Carbon Limestone Landfill where Hilcorp Energy is drilling some of its wells.
The second quake occurred after 11 a.m. and the epicenter was to the southeast of the first quake. It measured a 2.6 magnitude.
No injection wells are in the area where the quakes occurred, ODNR said.
The state took its action "out of an abundance of caution," ODNR said.
Hilcorp is the only driller in the area, the state said.
Injection wells have been blamed for small earthquakes in Ohio and other states, but horizontal drilling has not been blamed for causing earthquakes previously.
ODNR said it is beginning to analyze all data from today's quakes.
Chesapeake Energy Corp,the Oklahoma-based firm is the No. 1 driller in Ohio.
Rig Count Interactive Map by Baker Hughes, an energy services company.
Shale Sheet Fracking, a Youngstown Vindicator blog.
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Earthjustice, a national eco-group.
People's Oil and Gas Collaborative-Ohio, a grass-roots group in Northeast Ohio.
Concerned Citizens of Medina County, a grass-roots group.
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Pipeline, blog from Pittsburgh Post-Gazette on Marcellus shale drilling.
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