The report, which appears in the November issue of the journal Seismological Research Letters, identified nearly 400 tremors on a previously unmapped fault in Harrison County between Oct. 1 and Dec. 13, 2013.
That included 10 quakes of magnitudes of 1.7 to 2.2. That’s intense enough to have temporarily halted activity under Ohio’s new drilling permit rules had they been in place at the time, but is still considered minor.
The quakes fell along a fault lying directly under three hydraulic fracturing operations and tended to coincide with nearby activity, researchers found. About 190 quakes were detected in a single three-day period last October, beginning within hours of the start of fracking. None of the quakes was reported felt by people.These quakes are in addition to five tremors in March, 2014 near Youngstown that state geologists concluded were caused by fracking activity near a previously unknown fault. That incident spawned new state regulations aimed at limiting the possibility of seismic events related to unconventional oil and gas development.
The newest study supports the wisdom of Ohio's adoption of those regs - and the need for similar measures in other states.