Maine has recorded 500-plus earthquakes. But you wouldn’t know it with most of them. – The Boston Globe

Many New Englanders were jolted Monday morning when they felt their homes and offices rattle and heard a brief rumble as a 3.8-magnitude earthquake off the coast of Maine startled communities up to 250 miles away.

The US Geological Survey said this quake, whose epicenter was about 7 miles from southern Maine’s coastal town of York, was the strongest earthquake to strike the Northeast since last April’s 4.8 shaker in northern New Jersey, which was also felt across must of Southern New England, including Boston.

Leslie Sonder, an associate professor of Earth sciences at Dartmouth College, said although today’s quake was 10 times smaller in amplitude and 30 times less in energy than the New Jersey earthquake, we could still feel the tremor because of our region’s rock composition formed over the span of a billion years.

“The cold rock structure underlying the East Coast means that seismic waves are transmitted much more efficiently,” said Sonder. “As a result, vibrations from even small earthquakes are felt over much larger areas than they would be in western states such as California.”

Maine, like the other New England states, is no stranger to earthquakes. Quakes actually occur multiple times per month in our region. Minor earthquakes, generally a magnitude 2 or lower on the Richter scale, which measures the strength of earthquakes, are barely noticeable as we go about our day, according to experts. There have been hundreds of these low-end shakes on record.

“The Weston Observatory records about three to five minor earthquakes per month, but once you get to the magnitude of 3, we usually capture one per year,” said John Ebel, a senior research scientist at Weston Observatory at Boston College. “(Today’s) event was closer to a 4.0 magnitude, which happens about one in five years,” which goes for any earthquake at a strength of 3 or higher on the Richter scale.

Since 1900, there have been more than 500 earthquakes recorded across the state of Maine or within instrument range, according to the USGS. Most of them range from a 1 to 3 magnitude.

“When you get to or above a 5.0 magnitude, which happens about every 100 years, that’s where damage occurs,” added Ebel. “In 1755, we had a 6.2 earthquake by Cape Ann, Mass. which did a lot of damage.”

The largest earthquake ever recorded in or off the coast of Maine was in 1907, where a 5.7-magnitude quake occurred in extreme Downeast Maine, within Passamaquoddy Bay.

However, there has been a notable cluster of earthquakes whose epicenters have lied between Cape Ann off the North Shore, stretching to southern Maine, where the earthquake on Monday occurred. Experts suggest that the strike-slip fault across a several fault lines in the Gulf of Maine may indicate that they’re becoming more fragile, with the developing concentration of epicenters focusing south of Portland and off the New Hampshire and Massachusetts coast.

Ken Mahan can be reached at ken.mahan@globe.com. Follow him on Instagram @kenmahantheweatherman.