USGS-ANSS | ComCat |
---|---|
Local date | November 18, 1755 |
Local time | 04:30 |
Magnitude | 5.9 Mw [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) |
The 1755 Cape Ann earthquake took place off the coast of the British Province of Massachusetts Bay (present-day Massachusetts) on November 18. At between 6.0 and 6.3 on the Richter scale, it remains the largest earthquake in the history of Massachusetts. No one was killed, but it damaged hundreds of buildings in Boston and was felt as far north as Nova Scotia and as far south as South 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 a remotely triggered event from the 1755 Lisbon earthquake or its aftershocks.
The earthquake took place on November 18, 1755, at approximately 4:30 AM local time. Future President of the United States John Adams, then staying at his father's house in Braintree, 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 of Cape Ann. [3] The quake was felt as far north as Halifax, Nova Scotia, south to the Chesapeake Bay and South Carolina, and from Lake George and Lake Champlain in 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 several aftershocks, 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 the Richter scale, and the United States Geological Survey lists 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 old faults in 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 larger earthquake in Lisbon, Portugal, a few weeks prior, although there is not enough evidence to prove that they are linked. [7]
Boston and Cape Ann were the most heavily damaged. In Boston, damage was concentrated in areas of infill near 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-day Portland, Maine), Springfield, Massachusetts, and New 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 near Scituate, Lancaster, and Pembroke. 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 recorded tsunami in U.S. history. Observers in the Leeward Islands nearly 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]
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, including Jeremiah Newland's Verses Occasioned by the Earthquakes in the Month of November 1755 and Thomas Prince's Earthquakes the Works of God and Tokens of his Just Displeasure. Well before 1755, the new rational materialist ideas promulgated by Enlightenment scientists 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's Lecture on Earthquakes wrote:
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]
Since the 1755 earthquake, Boston and its surrounding towns have become a major metropolitan area. Much new construction has been built on infill, especially in the Back Bay area, 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 built from stone and brick, and are likely to collapse completely during a major earthquake. Given this, modern observers have expressed concern about the effects of another quake in such a major city. A 1990 study by the Massachusetts Emergency Management Agency estimated 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]
John Winthrop was an American mathematician, physicist and astronomer. He was the 2nd Hollis Professor of Mathematics and Natural Philosophy in Harvard College.
The 2006 Tonga earthquake occurred on 4 May at 04:26:35 local time with a moment magnitude of 8.0 and a maximum Mercalli intensity of VII. One injury occurred and a non-destructive tsunami was observed.
The 2006 Kīholo Bay earthquake occurred on October 15 at 07:07:49 local time with a magnitude of 6.7 and a maximum Mercalli intensity of VIII (Severe). The shock was centered 21 kilometers (13 mi) southwest of Puakō and 21 km (13 mi) north of Kailua-Kona, Hawaiʻi, just offshore of the Kona Airport, at a depth of 38.2 km (23.7 mi). It produced several aftershocks, including one that measured a magnitude of 6.1 seven minutes after the main shock. The Pacific Tsunami Warning Center measured a nondestructive tsunami of 4 in (100 mm) on the coast of the Big Island.
The 1992 Landers earthquake occurred on Sunday, June 28 with an epicenter near the town of Landers, California, in San Bernardino County. The shock had a moment magnitude of 7.3 and a maximum Mercalli intensity of IX (Violent).
The 1993 Scotts Mills earthquake, also known as the "Spring break quake", occurred in the U.S. state of Oregon on March 25 at 5:34 AM Pacific Standard Time. With a moment magnitude of 5.6 and a maximum perceived intensity of VII on the Mercalli intensity scale, it was the largest earthquake in the Pacific Northwest since the Elk Lake and Goat Rocks earthquakes of 1981. Ground motion was widely felt in Oregon's Willamette Valley, the Portland metropolitan area, and as far north as the Puget Sound area near Seattle, Washington.
The 1935 Temiskamingue earthquake occurred on November 1 with a moment magnitude of 6.1 and a maximum Mercalli intensity of VII. The event took place in the Western Quebec Seismic Zone in the Abitibi-Témiscamingue region of Quebec.
The 1999 Chamoli earthquake occurred on 29 March in the Chamoli district in the Indian state of Uttar Pradesh. Approximately 103 people died in the earthquake.
The 2002 Bou'in-Zahra earthquake occurred on 22 June 2002. The epicenter was near the city of Bou'in-Zahra in Qazvin Province, a region of northwestern Iran which is crossed by several major faults that is known for destructive earthquakes. The shock measured 6.5 on the Mwc scale, had a maximum Mercalli intensity of VIII (Severe), and was followed by more than 20 aftershocks. At least 230 people were killed and 1,500 more were injured.
The 1968 Illinois earthquake was the largest recorded earthquake in the U.S. Midwestern state of Illinois. Striking at 11:02 a.m. on November 9, it measured 5.3 on the Richter scale. Although no fatalities occurred, the event caused considerable structural damage to buildings, including the toppling of chimneys and shaking in Chicago, the region's largest city. The earthquake was one of the most widely felt in U.S. history, largely affecting 23 states over an area of 580,000 sq mi (1,500,000 km2). In studying its cause, scientists discovered the Cottage Grove Fault in the Southern Illinois Basin.
The 1985 Rapel Lake earthquake occurred on 8 April at 21:56:59 local time with a moment magnitude of 7.2 and a maximum perceived intensity of VI (Strong). The shock was centered 75 kilometres (47 mi) southwest of Santiago, Chile, with a focal depth of 37.8 km (23 mi).
On August 23, 2011, a magnitude 5.8 earthquake hit the Piedmont region of the U.S. state of Virginia at 1:51:04 p.m. EDT. The epicenter, in Louisa County, was 38 mi (61 km) northwest of Richmond and 5 mi (8 km) south-southwest of the town of Mineral. It was an intraplate earthquake with a maximum perceived intensity of VIII (Severe) on the Mercalli intensity scale. Several aftershocks, ranging up to 4.5 Mw in magnitude, occurred after the main tremor.
The 1980 Eureka earthquake occurred on November 8 at 02:27:34 local time along the northern coastal area of California in the United States. With a moment magnitude of 7.3 and a maximum Mercalli intensity of VII, this strike-slip earthquake was the largest to occur in California in 28 years. Although damage was considered light, several loss estimates equaled or exceeded $2 million, and six injuries resulted when two vehicles came down with the partial collapse of a highway overpass on US 101 in Fields Landing. The north coast of California experiences frequent plate boundary earthquakes near the Mendocino Triple Junction and intraplate events also occur within the Gorda Plate.
The geology of New Hampshire is similar to that of the rest of New England in comprising a series of metamorphosed sedimentary and volcanic rocks of Late Proterozoic to Devonian age, intruded by many plutons and dikes ranging in age from Late Proterozoic to early Cretaceous. New Hampshire is known as "the Granite State", but less than half is underlain by granite; much of it is schist or gneiss, both of which are metamorphic rocks.
The 1936 State Line earthquake struck at 23:08 Pacific time on July 15, 1936. The earthquake had an estimated magnitude of 5.8 and a maximum Mercalli intensity of VII. The epicenter was near the Oregon/Washington state line approximately 6 miles (9.7 km) northwest of Milton-Freewater, Oregon and southwest of Walla Walla, Washington and was felt throughout the Pacific Northwest, including as far away as Bonners Ferry, Idaho near the Canadian border and by seismographs as far away as San Diego, California.
The 2003 Fiordland earthquake struck the remote region of Fiordland in the South Island of New Zealand on 22 August 2003, at 12:12 am NZST. The epicentre was 12 kilometres (7.5 mi) deep, and was thought to be near Secretary Island at the entrance to Doubtful Sound. At 7.2 Ms magnitude, it was one of the largest quakes in the country for some time, and was the largest shallow quake since the 1968 Inangahua earthquake. There was an aftershock two hours later at 2:12 am, followed over several days by frequent small tremors; two months after the earthquake, there had been 8,000 aftershocks.
The 1921 Sevier Valley earthquake was a series of three earthquakes. The primary quake was a magnitude Mw6.3 earthquake that occurred on Thursday, 29 September 1921 at approximately 7:12 AM MT in Elsinore, Utah, United States. The first aftershock occurred in the evening on the same day, and a second aftershock occurred two days later on 1 October. No people were killed in the quake or in the subsequent aftershocks.
The 1895 Charleston earthquake, also known as the Halloween earthquake, occurred on October 31, at 05:07 CST near Charleston, Missouri. It had an estimated moment magnitude of 5.8–6.6 and evaluated Modified Mercalli intensity of VIII (Severe). The earthquake caused substantial property damage in the states of Missouri, Illinois, Ohio, Alabama, Iowa, Kentucky, Indiana, and Tennessee. Shaking was widespread, being felt across 23 states and even in Canada. At least two people died and seven were injured.
The 1992 Joshua Tree earthquake occurred at 9:50:25 p.m. PDT on April 22 in Southern California. The magnitude 6.2 earthquake struck under the Little San Bernardino Mountains, near the town of Joshua Tree, California. Though no deaths were reported, the earthquake caused 32 injuries. A maximum Mercalli intensity of VII was observed in Joshua Tree and caused light to moderate damage. The event preceded the Landers and Big Bear earthquakes by two months but is now recognized as the beginning of a series of major earthquakes that culminated in two events on June 28, 1992.
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.