If the earth trembles and no one feels it, is it an earthquake?
Just ask the U.S. Geological Survey.
Geologists recorded two earthquakes in the Charlotte region within 80 miles of each other over the weekend — a 2.1-magnitude quake that struck the foothills west of Winston-Salem and a 1.8-magnitude quake just outside Indian Trail.
Both were relatively shallow as measured by the USGS and no damages were reported.
In fact, most people appeared not to notice.
The first occurred at a depth of 13.8 kilometers — roughly 8.6 miles below the earth’s surface — just nine miles southeast of Blowing Rock. It happened shortly after midnight Sunday around 12:55 a.m.
Less than four hours later at roughly 4:30 a.m., the USGS recorded a second earthquake. It was slightly smaller and even closer to the earth’s surface with a depth of only 5.5 kilometers, or 3.4 miles, according to geologists.
The quake rattled 17 miles southeast of Charlotte near Indian Trail in Union County, just down the road from Porter Ridge Elementary, Middle and High Schools.
In both cases, only one person reported feeling the earthquake to the USGS.
These aren’t the first tremors North Carolina has seen in 2019.
One area of the North Carolina mountains had six small earthquakes in five days last month, according to the U.S. Geological Survey, as reported by the Charlotte Observer.
Only a handful of people there reported feeling most of them.
According to the N.C. Department of Environmental Quality, earthquakes aren’t uncommon in the state.
But “large, damaging seismic events” are not a regular occurrence.
Scientists are still studying why so many small quakes pop up between Tennessee, western North Carolina and northern Georgia in what’s known as the Eastern Tennessee seismic zone, the NCDEQ reported.
“This area is not a seismically active area like California and the West Coast,” according to the state agency. “In California there are many active faults where large, damaging earthquakes occur frequently. In contrast, there are no active fault zones in North Carolina.”
One of the strongest quakes to rattle the region reportedly occurred in Buncombe County in 1916 with a magnitude of 5.2.
Before that, a 6.7-magnitude earthquake struck Charleston in 1886 and was felt up and down the east coast, according to the NCDEQ.