It’s the sort of event that is easy to joke about in retrospect. After all, the Valentine’s Day earthquake that struck the heart of Palmetto State rumbled through and left structures mostly unscathed.
Even seismologists don’t seem to give it much respect.
“If you had felt the earth move on Valentine’s Day, it may not have been you,” College of Charleston associate professor of geology Steve Jaume joked Monday.
Adding to the belittling of the event where dozens of pictures of knocked-over lamps were paired on social media with mock promises to rebuild, the 4.1 magnitude earthquake is called a “light earthquake,” according to seismology language.
But Jaume said, like a near-miss by a hurricane or — say — the entire state shutting down twice in two weeks for an ice storm, there are lessons to learn from this event: First, there is the potential for earthquakes across much of the state, not just along fault lines in the Lowcountry. Second: Jaume says it’s what is under your feet that matters.
According to the seismologist, Union County experienced a 5-magnitude earthquake in 1913, which is relatively recently in geology terms.
“People just haven’t experienced it recently,” Jaume said. “They don’t happen as often in the Upstate (or Midlands) as they do in the Summerville area but there actually have been some other ones.”
The other big takeaway: if the same size quake struck the notorious Middleton Fault — which shook and leveled much of the Charleston area in 1886 — the Lowcountry likely would have suffered damage.
And that’s due to what the fault is shaking.
“We would expect, for the same size earthquake, proportionally more damage here in the Lowcountry,” Jaume said. “They have hard rock very near the surface and thin to no sediment on top of it (in the Midlands). Down here, we have several thousand feet (of sediment) underneath the surface … For a specific earthquake, where you are and what’s under your feet matters.”
While the little earthquake deserves a little respect, Jaume warned against extrapolating any predictions from the event.
“When you have one earthquake it does not mean it’s a harbinger of something bigger coming. Sometimes we find out things in retrospect — and that’s the problem, in retrospect — we’ll find out they were fore-shocks to a bigger earthquake but when there’s one earthquake we cannot tell simply by its occurrence that it’s telling you something about the future,” Jaume said. “Hurricanes and volcanoes are some of the more predictable ones… Earthquakes, no. Earthquakes, most of the time, are a surprise.”
