Opinion/Al Southwick: Could an earthquake really rock New England? We are 265 years overdue
On Nov. 8, a 3.6 magnitude earthquake struck Buzzard’s Bay off the coast of New Bedford. Reverberations were felt up to 100 miles away, across Massachusetts, Rhode Island, and parts of Connecticut and New York. News outlets scrambled to interview local residents who felt the ground shake their homes. Seismologists explained that New England earthquakes, while uncommon and usually minor, are by no means unheard of.
The last bad one we had took place on Nov. 18, 1755, a date long remembered.
It’s sometimes called the Boston Earthquake and sometimes the Cape Ann Earthquake. Its epicenter is thought to have been in the Atlantic Ocean about 25 miles east of Gloucester. Estimates say that it would have registered between 6.0 and 6.3 on the modern Richter scale. It was an occasion to remember as chronicled by John E. Ebel, director of the Weston observatory of Boston College:
“At about 4:30 in the morning on 18 November, 1755, a strong earthquake rocked the New England area. Observers reported damage to chimneys, brick buildings and stone walls in coastal communities from Portland, Maine to south of Boston … Chimneys were also damaged as far away as Springfield, Massachusetts, and New Haven, Connecticut. The earthquake was felt at Halifax, Nova Scotia to the northeast, Lake Champlain to the northwest, and Winyah, South Carolina to the southwest. The crew of a ship in deep water about 70 leagues east of Boston thought it had run aground and only realized it had felt an earthquake after it arrived at Boston later that same day.
“The 1755 earthquake rocked Boston, with the shaking lasting more than a minute. According to contemporary reports, as many as 1,500 chimneys were shattered or thrown down in part, the gable ends of about 15 brick buildings were broken out, and some church steeples ended up tilted due to the shaking. Falling chimney bricks created holes in the roofs of some houses. Some streets, particularly those on manmade ground along the water, were so covered with bricks and debris that passage by horse-drawn carriage was impossible. Many homes lost china and glassware that was thrown from shelves and shattered. A distiller’s cistern filled with liquor broke apart and lost its contents.”
We don’t have many details of the earthquake’s impact here, there being no newspaper in Worcester County at that time. We do know that one man, Christian Angel, working in a “silver” mine in Sterling, was buried alive when the ground shook. He is the only known fatality in these parts. We can assume that, if the quake shook down chimneys in Springfield and New Haven, it did even more damage hereabouts. We can imagine the cries of alarm and the feeling of panic as trees swayed violently, fields and meadows trembled underfoot and pottery fell off shelves and crashed below.
The Boston Earthquake was an aftershock from the gigantic Lisbon Earthquake that had leveled Lisbon, Portugal, a few days before. That cataclysm, estimated as an 8 or 9 on the modern Richter scale, was the most devastating natural catastrophe to hit western Europe since Roman times. The first shock struck on Nov. 1, at about 9 in the morning.
According to one account: ”Suddenly the city began to shudder violently, its tall medieval spires waving like a cornfield in the breeze … In the ancient cathedral, the Basilica de Santa Maria, the nave rocked and the massive chandeliers began swinging crazily. . . . Then came a second, even more powerful shock. And with it, the ornate façade of every great building in the square … broke away and cascaded forward.”
Until that moment, Lisbon had been one of the leading cities in western Europe, right up there with London and Paris. With 250,000 people, it was a center of culture, financial activity and exploration. Within minutes it was reduced to smoky, dusty rubble punctuated by human groans and screams. An estimated 60,000 to 100,000 lost their lives.
Since then, New England has been mildly shaken by quakes from time to time. One series of tremors on March 1, 1925, was felt throughout Worcester County, from Fitchburg to Worcester, and caused a lot of speculation.
What if another quake like that in 1755 hit New England today? What would happen? That question was studied 15 years ago by the Massachusetts Civil Defense Agency. Its report is sobering:
“The occurrence of a Richter magnitude 6.25 earthquake off Cape Ann, Massachusetts … would cause damage in the range of 2 to 10 billion dollars … in the Boston metropolitan area (within Route 128) due to ground shaking, with significant additional losses due to secondary effects such as soil liquefaction failures, fires and economic interruptions. Hundreds of deaths and thousands of major and minor injuries would be expected … Thousands of people could be displaced from their homes … Additional damage may also be experienced outside the 128 area, especially closer to the earthquake epicenter.”
So even if we don’t worry much about volcanoes, we know that hurricanes and tornadoes are always possible. As for earthquakes, they may not happen in this century or even in this millennium, but it is sobering to think that if the tectonic plates under Boston and Gloucester shift again, we could see a repeat of 1755.
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