A total of nine quakes have been reported in the past five weeks, sending seismic waves through shoreline communities.
The temblors range in magnitude from 1.8 to 2.8.
Jeff Fox, a seismologist with the Ohio Department of Natural Resources, told FOX 8, “This is kind of like normal seismic activity for Northeast Ohio, but it is a little unusual that we’ve had so many in a such a short amount of time.”
Fox says it appears all of the earthquakes are happening along the same fault line under the lake.
“That part of Ohio is actually very faulted. There’s a lot of complex geology underneath the surface that we don’t really normally see, from the early continental building of the Appalachian Mountains and things like that, so there’s a lot going on geologically up there. It’s very complex,” he said.
What’s being felt by Lake County residents are what’s known as intraplate earthquakes, and one theory that seismologists have been investigating is whether higher water levels on the lake in recent years may be to blame for the seismic activity.
“It would be nice if we could drill down there ourselves and look what’s going on, but that’s the trouble, you know, with stuff that’s buried miles and miles under solid rock. It’s not quite that easy,” he said.
Researchers with the Ohio Geological Survey believe a 4.0 magnitude earthquake in 2019 happened along the same fault line and the recent quakes may actually be aftershocks from that original seismic event.
We asked if the recent temblors may be a sign that a large damaging quake is building under the surface.
Fox responded, “That’s the million-dollar question there, we don’t know yet. One thing that can be said about earthquakes is they’re actually relieving stress on faults, you know because there’s stress being built upon the fault. Every time you have an earthquake happen, all of that stress is relieved.”
But the quakes under the lake could also be a temporary problem.
“They might just continue to pop off, small earthquakes here and there for the next few weeks, months, years, and then they just stop for whatever reason. We just don’t know. It’s just too complex of a phenomenon,” he said.
As a result of the increase in earthquakes reported in Ohio in recent years, ODNR is planning to install additional seismometers along the lakeshore later this year.