Small earthquake rumbles Concord area Wednesday, latest in a series
March 07. 2018 8:13PM
Union Leader Staff
A small earthquake rattled the Concord area early Wednesday, according to the U.S. Geological Survey. There have been more than a half-dozen since last summer.
The quake, which rumbled through about 5:07 a.m. with a magnitude of 2.4, was centered 3.7 miles deep and about two miles northeast of Contoocook, the USGS said.
The latest temblor follows several recent quakes in the Granite State.
The morning of Thursday, Feb. 15, a magnitude 2.7 earthquake was felt throughout southeastern New Hampshire, which the USGS said was centered to the west of Exeter. A magnitude 2 earthquake was felt the morning of Tuesday, Feb. 13, centered about 1.2 miles from Sanbornton. A 1.6-magnitude earthquake was felt along the Maine-NH border on Wednesday, Jan. 25.
Officials from the New Hampshire Homeland Security and Emergency Management said that while there have been no reports of damage or injuries, residents should be prepared for future quakes.
“This quake serves as a reminder to all of us: an earthquake can occur at any time with no warning. Put your emergency plan together now and practice it regularly,” said HSEM Director Perry Plummer.
According to the USGS, New Hampshire has endured hundreds of earthquakes throughout its history.
On Nov. 9, 1810, Exeter was rattled by a magnitude-6 earthquake, accompanied by a noise like a 'great explosion' directly beneath the area. Windows were broken in Portsmouth.
The Concord region experienced several shocks between 1872 and 1891. Two moderate earthquakes, the first on Nov. 18, 1872, and the second on Dec. 19, 1882, were felt there. The first one lasted 10 seconds and was felt up in Laconia, while the 1882 tremor shook buildings in Dover and Pittsfield.
According to the USGS, the two largest quakes in New Hampshire history occurred four days apart in 1940, Dec. 20 and 24, both centered in Ossipee. Both quakes measured 5.5 on the Richter Scale. Tamworth sustained the most damage, mostly to older homes and chimneys. Reports stated well water was muddy for several days, and minor damage such as cracked walls, broken water pipes, fallen plaster, and broken furniture also occurred.
The Ossipee Mountains are a ring dike, the remnants of an ancient stratovolcanic from Earth's Cretaceous period 145 million years ago. Such volanos are characterized by steep sides and a towering conical shape, Mount Etna in Sicily and Mount Fuji in Japan are examples.
One of the earliest documented earthquakes in New Hampshire was in 1663. Believed to have originated in the St. Lawrence River fault zone, it reportedly was powerful enough to collapse chimneys.