A 5.4-magnitude earthquake shook Quebec early Sunday, according to the Geological Survey of Canada. It was centered near the city of Riviere-du-Loup on the St. Lawrence River, and was felt as far away as Montreal.
The quake’s epicenter was under the St. Lawrence River. No immediate damage or injuries were reported.
The quake was classified as “moderate,” meaning it could cause minor damage in the area immediately around the epicenter.
Quakes are common in some areas of Quebec, but most are far smaller than Sunday’s temblor.
Some small quakes have also rattled the U.S. lately, with a magnitude 4.6 quake striking central Arizona last week and a 2.0 hitting Maryland in late February. Neither caused any damage, but both shook nerves a little.
Some regions are more accustomed to quakes than are others. “When people are not very used to having earthquakes, they will wonder if the quake they felt means something bigger is coming,” said Waverly Person, a seismologist with the U.S. Geological Survey’s National Earthquake Information Center. “In Maryland, people get really excited about it.”
Maryland’s 2.0 was not that unusual. “We average one of those about once each year,” said Jerry Baum, program chief for the Maryland Geological Survey. “They vary from (magnitude) .5 to 2.0, but most are between .5 and 1.0.”
The largest in Maryland history was a 3.5, yet Baum added that even those that are very small can still be felt.
“People do call in to let us know they felt them, but frequently they’ll call the police or fire department first to say what they felt and then ask if it was an earthquake,” he explained.
And just because earthquakes are not commonplace in some areas does not mean those areas are not monitored for seismic activity. The USGS has a federal mandate to report all earthquakes, said spokesperson Clarice Ransom. They monitor seismic activity in the entire country, not to mention around the world through their network of seismologists.
Last week's moderate quake in Arizona was the latest in a series, explained Person. “The 4.6 was the largest of the series which started on the 28th of January. Yet there are series of quakes scattered across the U.S. on a regular basis.”
The region along the New Madrid fault line – stretching from Indiana to Mississippi and Louisiana along the Mississippi River – experiences very frequent seismic activity. Most of it, however, comes in the form of small quakes under magnitude 4.0.
Experts say to not misjudge the New Madrid seismic zone, though. The fault line produced three 8.0 earthquakes in 1811 and 1812, which changed the region’s landscape and shook church bells in towns as far away as Boston.
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