The1755 Cape Ann earthquaketook place off the coast of the BritishProvince of Massachusetts Bay(present-day Massachusetts) on November 18. At between 6.0 and 6.3 on theRichter scale,it remains the largestearthquakein the history of Massachusetts. No one was killed, but it damaged hundreds of buildings in Boston and was felt as far north asNova Scotiaand as far south asSouth Carolina.[2]Sailors on a ship more than 200 miles (320 km) offshore felt the quake, and mistook it at first for their ship running aground. Many residents of Boston and the surrounding areas attributed the quake to God, and it occasioned a brief increase in religious fervor in the city. Modern studies estimate that if a similar quake shook Boston today, it would result in as much as$5 billion in damage and hundreds of deaths.[3]Some discussion has revolved around the idea that this may have been aremotely triggered eventfrom the1755 Lisbon earthquakeor its aftershocks.
   Cape Ann | |
| USGS-ANSS | ComCat |
|---|---|
| Local date | November 18, 1755 |
| Local time | 04:30 |
| Magnitude | 5.9Mw[1] |
| Epicenter | 42°42′N70°12′W/ 42.7°N 70.2°W |
| Areas affected | British America,Province of Massachusetts Bay |
| Max.intensity | MMI VIII (Severe) |
Epicenter
editThe earthquake took place on November 18, 1755, at approximately 4:30 AM local time. FuturePresident of the United StatesJohn Adams,then staying at his father's house inBraintree, Massachusetts,was awakened by the quake, which impressed him so much that he began a diary that night. He wrote that the quake "continued near four minutes" and that "[t]he house seemed to rock and reel and crack as if it would fall in ruins about us."[4]Its epicenter is believed to have been offshore, approximately 24 miles (39 km) east ofCape Ann.[3]The quake was felt as far north asHalifax,Nova Scotia,south to theChesapeake BayandSouth Carolina,and fromLake GeorgeandLake Champlainin the northwest to a ship 200 miles (320 km) off the east coast.[5][6]Sailors on the ship reported that the quake was so strong, they had feared that they had run aground.[5]The region experienced severalaftershocks,the first of which was a little more than an hour after the quake. Most of these aftershocks could not be felt in Boston, affecting only the northeastern coast of the colony.[6]
Modern research has estimated that the quake was between 6.0 and 6.3 on theRichter scale,and theUnited States Geological Surveylists it as the largest earthquake in the history of Massachusetts.[6]Scientists are unclear on the causes of this and other quakes in the northeastern United States. There are a number of oldfaultsin the region, but none of them is known still to be active.[3]It is possible that the Cape Ann earthquake may have been remotely triggered by a largerearthquake in Lisbon, Portugal,a few weeks prior, although there is not enough evidence to prove that they are linked.[7]
Damage
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Boston and Cape Ann were the most heavily damaged. In Boston, damage was concentrated in areas ofinfillnear the harbor; infill is less sturdy in earthquakes than solid land. From 1,300 to 1,600 chimneys in the city were damaged in some way, the gable ends of some houses collapsed, and a number of roofs were damaged by falling chimneys.[5]Stone chimneys and buildings were damaged in Falmouth (present-dayPortland, Maine),Springfield, Massachusetts,andNew Haven, Connecticut,as well. Some church steeples in Boston were damaged, ending up tilted from vertical.[3][6]Stone fencing in rural areas was damaged. Observers also reported that several springs dried up, new ones were created, and cracks appeared in the ground nearScituate,Lancaster,andPembroke.In this last town, observers noted water and fine sand coming from the crack.[5]Non-structural damage was minor; residents reported damage to china and glassware, and a distiller lost some of his product after a cistern was damaged.[6]The Cape Ann earthquake may also have created the first recordedtsunamiin U.S. history. Observers in theLeeward Islandsnearly 1,000 miles (1,600 km) south of Cape Ann, reported a receding of water followed by a large wave that lifted several boats ashore and left fish floundering on the beach.[8]
Legacy
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Many Massachusetts residents of the time perceived the quake as punishment from God for immoral behavior.[8]In the days after the earthquake, special prayer services were held and civic authorities declared fast days. A number of sermons and other writings were published as a consequence, includingJeremiah Newland'sVerses Occasioned by the Earthquakes in the Month of November 1755andThomas Prince'sEarthquakes the Works of God and Tokens of his Just Displeasure.Well before 1755, the new rational materialist ideas promulgated byEnlightenmentscientists had begun to heavily influence the better-educated citizens of colonial America; therefore not all explanations of the event were theological.John Winthrop,a Harvard professor, proposed an alternate explanation having to do with heat and chemical vapors inside the surface of the earth.[6]John Adams, in comments in the margins of Winthrop'sLecture on Earthquakeswrote:
I am not able to satisfy myself, whether the very general if not universal apprehension that Thunder, Earthquakes, Pestilence, Famine &c. are designed merely as Punishments of sins and Warnings to forsake, is natural to Mankind, or whether it was artfully propagated, or whether it was derived from Revelation. An Imagination that those Things are of no Use in Nature but to punish and alarm and arouse sinners, could not be derived from real Revelation, because it is far from being true, tho few Persons can be persuaded to think so.[9]
Many of the buildings in modern Boston and its surroundings are built on infill, especially in theBack Bayarea, which may be prone to greater shaking and to compaction of the sand and gravel used as fill. Many older buildings in the Boston area are masonry, and may to collapse completely during a major earthquake. A 1990 study by theMassachusetts Emergency Management Agencyestimated potential financial losses at between $4 billion and $5 billion, and potential loss of life in the hundreds.[3]As a consequence, the state has updated building codes and zoning laws to require that new construction and additions in vulnerable areas be built to resist earthquakes.[3]
See also
editReferences
edit- ^Ebel, J.E. (2006)."The Cape Ann, Massachusetts earthquake of 1755: a 250th anniversary perspective".Seismological Research Letters.77(1).Seismological Society of America:74.Bibcode:2006SeiRL..77...74E.doi:10.1785/gssrl.77.1.74.
- ^Ballard C. Campbell, ed.American Disasters: 201 Calamities That Shook the Nation(2008) pp 28–30
- ^abcdefNewman, William A.; Holton, Wilfred E. (2006).Boston's Back Bay: The Story of America's Greatest Nineteenth-century Landfill Project.University Press of New England. pp.177–180.ISBN978-1-55553-651-0.
- ^Adams, John (18 November 1755)."November 1755 – from the Diary of John Adams".Founders Online – The Adams Papers.U.S. National Archives.Retrieved13 January2021.
We had a severe Shock of an Earthquake. It continued near four minutes. I was then at my Fathers in Braintree, and awoke out of my sleep in the midst of it. The house seemed to rock and reel and crack as if it would fall in ruins about us. Chimnies were shatter'd by it within one mile of my Fathers house.
- ^abcd"Cape Ann, Massachusetts".Historical Earthquakes.United States Geological Survey. Archived fromthe originalon 2009-05-08.Retrieved2009-10-17.
- ^abcdefEbel, John. E."The Cape Ann Earthquake of November 1755".The Massachusetts Historical Society.Retrieved2018-04-19.
- ^Hough, Susan Elizabeth;Bilham, Roger G. (2006).After the Earth Quakes: Elastic Rebound on an Urban Planet.Oxford University Press US. pp. 23–24.ISBN978-0-19-517913-2.
- ^abGunn, Angus M. (2007).Encyclopedia of Disasters: Environmental Catastrophes and Human Tragedies.Greenwood Publishing Group. pp. 81–82.ISBN978-0-313-34002-4.
- ^Adams, John (1758)."Marginalia in Winthrop's Lecture on Earthquakes, December 1758[?] – from the Diary of John Adams".Founders Online – The Adams Papers.U.S. National Archives.Retrieved13 January2021.