East Coast Earthquake: Magnitude 4.6
Felt intensely in New England, a magnitude 4.6 earthquake struck near Hollis, Maine at 7:12 PM local time, October 16, about 85 miles north of Boston. The earthquake rippled out from the epicenter, which was very shallow at 5km (about 3 miles under the earth’s surface), which was a reason why the earthquake was felt widely throughout the region.
Calls are streaming in to news centers and other stations from alarmed residents. For the moment, it feels like California in the northeast…
There have been reports that phone lines in Maine are down. (update: probable cause due to heavy call traffic)
Residents all across Maine, New Hampshire, Massachusetts, Rhode Island and other New England states report that their homes were shaking. New reports from as far away as Pennsylvania.
A spokeswoman for the Maine Emergency Management Agency, said her dogs started barking several seconds before the quake.
The Seabrook Station nuclear plant, about 63 miles away in New Hampshire, declared an unusual event — the lowest of four emergency classifications, but said it was not affected. The plant has been offline for refueling.
Experts say the region’s geology can make the effects felt in an area up to 10 times larger than quakes of similar size on the West Coast.
Maine Earthquake Shake Map
People in New England, and in its geological extension southward through Long Island, have felt small earthquakes and suffered damage from infrequent larger ones since colonial times. Moderately damaging earthquakes strike somewhere in the region every few decades, and smaller earthquakes are felt roughly twice a year. The Boston area was damaged three times within 28 years in the middle 1700’s, and New York City was damaged in 1737 and 1884. The largest known New England earthquakes occurred in 1638 (magnitude 6.5) in Vermont or New Hampshire, and in 1755 (magnitude 5.8) offshore from Cape Ann northeast of Boston. The Cape Ann earthquake caused severe damage to the Boston waterfront. The most recent New England earthquake to cause moderate damage occurred in 1940 (magnitude 5.6) in central New Hampshire.
How about that… earthquakes can strike literally anywhere, and is all the more reason to Be Prepared, no matter where you live.
Update: USGS later downgraded the earthquake to a 4.0, which is very typical behavior for the agency. Having followed their reporting for years, I know that it is extremely rare for them to upgrade a magnitude, but very common to bring it lower, perhaps to bring down the anxiety of the masses, or perhaps due to a very consistent error or problem in their method of recording initial magnitude.