December 10, 2012
HAZARD – Officials with the Kentucky Geological Survey (KGS) will be installing a new earthquake monitoring station in Perry County, which will be the first planned for the region in order to increase geologists’ capacity to measure seismic activity.
Just a few short weeks have passed since a magnitude 4.3 earthquake centered near Whitesburg struck southeastern Kentucky, though at present the KGS, a department of the University of Kentucky, does not operate any monitoring stations south of Powell County. Jim Cobb is the state geologist and director of the Kentucky Geological Survey, and said the department will add three new monitoring stations in the region over the next year, beginning with one in Hazard at the Perry County Public Library.
The southeastern region of Kentucky does see fairly regular seismic activity from the East Tennessee Seismic Zone, an area that stretches from northern Alabama to southwestern Virginia. “It’s a rather diffuse area,” Cobb explained, “but there are pretty frequent earthquakes there, mostly small, but occasionally up to a (magnitude) five or so, and could be in the past a little stronger. That activity has kind of got our attention.”
The idea of the new station in Hazard will be to monitor earthquakes and mine blasts in the area, and the station will be equipped with both velocity and acceleration sensors, explained Seth Carpenter, with the Geologic Hazards Section of the KGS. The acceleration sensor will measure larger earthquakes, while the velocity sensor will measure smaller movements in the Earth’s crust.
The public will also get a chance to interact with the station, as Carpenter noted that he plans to set up a computer at the library which will provide data from the station as well as the KGS network. “There should be real-time capabilities on it,” he said.
Kentucky as a whole is active in terms of seismic activity, with a few active geological fault zones around the state, such as the New Madrid, though none are actually inside the state’s borders. Additional monitoring stations will allow geologists with the KGS to better pinpoint the epicenter of an earthquake when it does happen.
“When all the epicenters are plotted on a map, an outline of the fault system becomes obvious to everyone,” Cobb said. “We don’t have that for East Tennessee, and we would like to improve the recording of earthquakes so that they begin to define an area for us.”
Plans for these new stations in the region have been in the works for more than a year, well before the most recent earthquake in Letcher County, and that particular tremor, Cobb noted, is not an indication in and of itself that something bigger is coming down the pike at a specific time.
“Those kinds of things cannot be predicted,” he said. “The only thing that can be predicted is if you do have a level of activity, which the East Tennessee Seismic Zone does have, then there’s potential for a big one. But we don’t know when.”
Officials with the KGS are expected to be in Hazard on Monday and Tuesday to install the new station, and Carpenter noted that he hopes to install two more stations in the region, one in Pike County and a third near the London area.