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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.

Last week, the Maine Dept. of Marine Resources advised lobstermen that 90 or more North Atlantic right whales were feeding within Jeffreys Basin, in the Gulf of Maine, in an area overlapped with lobster gear. They remain there this weekend, and DMR Commissioner Patrick Keliher  issued another advisory Jan. 24. It follows:

“A large number of endangered North Atlantic right whales remain off the western edge of Jeffreys Ledge.  As many as 90 individual right whales have been identified in this area over the past couple of weeks.    

“The most recent information suggests the whales may be feeding within Jeffreys Basin and the largest overlap of gear and whales appears to be in depths greater than 300 feet. I am strongly urging any lobster fisherman with trap gear set in greater than 300 feet of water inside the following area of Zone G to remove gear completely or drop one endline in order to reduce the number of vertical lines being fished. The identified area, as shown in the attached graphic, includes bottom in 300+ feet of water east of Boon Island Light and west of Jeffreys Ledge. 

“As I stated last week, there is potential for any entanglement that might occur to be linked not just to the Maine fishery, but potentially to an individual fisherman. One entanglement will eventually lead to additional federal restrictions, including closed areas and limiting the use of traditional gear (i.e. rope).  

“Let me be clear, this is not mandatory, this would be a voluntary action on your part – however failure of the industry to self-regulate your activity could be costly in the long run. I urge fishermen to work together to reduce the amount of gear and endlines in the area in order to protect both the right whales as well as the future of the Maine lobster fishery.  

“The Maine Marine Patrol, NOAA Law Enforcement and the US Coast Guard will not be enforcing state or federal regulations requiring two endlines for trap gear being fished in the Jefferys Ledge area described above.  Again, please drop one endline to reduce the risk to right whales.  To minimize potential for lost gear, NOAA will notify the mobile gear fleet through VMS that fixed gear fishermen may be using only one endline in this area. 

“Boats of any size can injure or kill a whale if a collision occurs. A voluntary slow zone of 10 knots remains in effect for this area.  Right whales can be difficult to see on the surface so do not assume that if you do not see a right whale, it is not there; there are large surface active groups in the area. Vessels transiting the area at night should be extremely careful as a collision with a right whale will not only injure the whale but also puts your safety at risk. Do not assume a right whale will avoid your vessel.  

“I will continue to monitor this situation and will reach out to you as we have additional information.”