new madrid earthquake 1811 magnitude
The 1811â12 New Madrid earthquakes were an intense intraplate earthquake series beginning with an initial earthquake of moment magnitude 7.5â7.9 on December 16, 1811 â¦ The maximum documented intensity for both earthquakes on December 16, 1811, is MM intensity VIII at Richmond, Kentucky. The most seriously affected areas were in southeastern Missouri, northeastern Arkansas, southwestern Kentucky, and northwestern Tennessee. Reelfoot Lake, near Tiptonville, Tennessee. The strongest aftershock, a magnitude-7.0 tremor that became known as the âdawn aftershock,â occurred later that day at 7:15 am. At dawnâs first light Pierce beheld the full extent of devastation wrought by the nighttime shocks: âthe earth, river &c torn with furious convulsions, opened in huge trenches whose deep jaws were instantaneously closed: there through a thousand vents sulphureous streams gushed from its very bowels leaving vast and almost unfathomable caverns. New Madrid resident Eliza Bryan vividly recalled the awful noises of the first shocks replete with the distant reverberations of hoarse and vibrating thunder, the cracking sounds of falling trees, and the riverâs thunderous roar, all punctuated by the smell of sulfur. The New Madrid fault system was responsible for the 1811â12 New Madrid earthquakes, and has the potential to produce large earthquakes in the future. Some scientists estimate the February quake at 8.8 magnitude. The 1811 â 12 New Madrid earthquakes were an intense intraplate earthquake series beginning with an initial earthquake of moment magnitude 7.5 â 7.9 on December 16, 1811 followed by a moment magnitude 7.4 aftershock on the same day. Bradbury, who viewed these events from a scientific perspective, chose not to challenge the settlerâs firmly held beliefs. Initially, they suspected that hostile Indians had caused the mischief by unleashing their tethered vessel from its moorings, but a succession of shocks soon alerted them to the true source of the mayhem. When John Bradbury entered a house near the Chickasaw Bluffs in which there was an open Bible on the table, one of the occupants attributed the cause of the recurring shocks to the Great Comet of 1811 that had appeared a few months earlier. Damage to the landscape included the warping of the ground through subsidence (sinking) and uplift, sand blows, ground cracking, landslides, and stream bank calving. The recent minor tremors of the Mississippi valley recall the New Madrid earthquakes of 1811-12. A series of minor earth tremors (maximum magnitude of just 2.6) have not so much shaken as shivered the Mississippi valley between Paducah and Memphis over the past 30 days. In American settlements and on Native ground alike, people debated the earthquakesâ causes and struggled to discover the cataclysmsâ larger meanings and purposes. Boatman on the river reported the riverbed rose up to 15 feet causing the Mississippi to flow backwards and create two temporary waterfalls. Every where Nature itself seemed tottering on the verge of dissolution.â. It was followed by at least three large aftershocks with magnitudes that ranged from 6.0 to 7.0 over the course of the next 48 hours. A slightly different version of this essay, âTurbulence and Terror: The New Madrid Earthquakes, 1811â1812,â appeared in the November 2017 issue of We Proceeded On, published by the Lewis and Clark Trail Heritage Foundation. They remain the most powerful earthquakes to hit the contiguous United States east of the Rocky Mountains in recorded history. More-precise figures have been presented by the United States Geological Survey (USGS) Earthquake Hazards Program: magnitude 7.7 for the December earthquake and magnitudes 7.5 and 7.7 for the January and February earthquakes, respectively. Nuttli, O. W. (1973). Some areas sank, while others were uplifted. The potential for earthquakes in the New Madrid region continues to the present day. These are estimated at between 7 and 8 on the richter scale. Bulletin of the Seismological Society of America, 92(8), 3259-3268. During the winter of 1811 to 1812, the sparsely populated New Madrid, Mo., area was jolted by a series of three powerful earthquakes now estimated to have been of magnitude 7.5 to 8.3. This would make a total of seven earthquakes of magnitude M6.0-7.5 occurring in the period December 16, 1811 through February 7, 1812. Rev. Citation Hough, S. E. (2002). Explains differences, and Mercalli intensity scale. The New Madrid region continues to have the highest level of seismicity activity in the United States east of the Rockies. There were two other large earthquakes- one on January 23, 1812 and February 7, 1812. By Barbara Lewellen Introduction. They remain the most powerful earthquakes to hit the contiguous United States east of the Rocky Mountains in recorded history. Three of the earthquakes are on the list of Americaâs top earthquakes: the first one on December 16, 1811, a magnitude of 8.1 on the Richter scale; the second on January 23, 1812, at 7.8; and the third on February 7, 1812, at as much as 8.8 magnitude. On December 16, 1811, the 400 residents of New Madrid, Missouri, were shaken out of their beds at two in the morning by a violent earthquake. Research indicates that the 1811â1812 New Madrid earthquake sequence was preceded by at least two similar earthquake sequences in about 1450 AD and 900 AD, and that over the past 5,000 years or so, other large earthquakes have also occurred in the region surrounding the main area of the currently active New Madrid seismic zone. Chicago: University of Chicago Press, 2013. The backwoods claimant of spiritual knowledge feared that these ominous occurrences might portend the approach of the end times. New Madrid, Territory, Missouri, March 22, 1816. In the known history of the world, no other earthquakes have lasted so long or produced so much evidence of damage as the New Madrid earthquakes. In addition, Lake St. Francis in Arkansas, a water body formed by subsidence that followed earlier earthquakes associated with the NMSZ, expanded. John Bradbury, the English naturalist and explorer of North Americaâs interior regions, had no such hesitation about the cause of his boatâs sudden and powerful convulsions on that fateful night. Possible causes of the New Madrid earthquakes, https://www.britannica.com/event/New-Madrid-earthquakes-of-1811-1812, USGS Earthquake Hazards - The New Madrid Seismic Zone. There were thousands of aftershocks, of which 1,874 were large enough to be felt in Louisville, Kentucky, about 190 miles (300 km) away. Fissures opened in the ground; some were filled with water from the nearby Mississippi River or wetlands, which was later expelled high into the air when the fissures closed. Hundreds of aftershocks were felt in 1813. Copyright Â© 2020 State Historical Society of Missouri. The fault line runs some 150 miles from Marked Tree, Arkansas, to Cairo, Illinois, passing through southeast Missouri. The magnitude of the December 16, 1811, event ranged from 6.7 to 8.1, whereas the ranges for the earthquakes of January 23 and February 7, 1812, were 6.8â7.8 and 7.0â8.8, respectively. According to his reckoning, the earth had become lodged between the cometâs two horns and was now attempting to dislodge itself. The magnitude of the December 16, 1811, event ranged from 6.7 to 8.1, whereas the ranges for the earthquakes of January 23 and February 7, 1812, were 6.8â7.8 and 7.0â8.8, respectively. New Madrid earthquakes of 1811â12, series of three large earthquakes that occurred near New Madrid, Missouri, between December 1811 and February 1812. William Leigh Pierce, a literate twenty-one-year-old traveler, was en route to New Orleans on a flatboat in December 1811 when a violent and convulsive agitation awakened him in the dead of night. John P. Rafferty writes about Earth processes and the environment. The 1811â12 New Madrid earthquakes were an intense intraplate earthquake series beginning with an initial earthquake of moment magnitude (7.5 -7.9) on December 16, 1811 followed by a moment magnitude 7.4 aftershock on the same day. 1812, January 23, 15:00 UTC, New Madrid, Missouri Magnitude ~7.0 - 7.8 This is the third principal shock of the 1811-1812 sequence. The shock, whose epicentre was also located near New Madrid, Missouri, shook the region at 3:45 am and resulted in the destruction of New Madrid. U.S. Pres. The third principal earthquake, on February 7, however, matched or exceeded the strength and severity of the December 16 event. Reading assignment. The upthrusting of the land some 15 miles (24 km) to the south of the epicentre pushed water into a basin that dropped 5 to 20 feet (1.5 to 6 metres) and created Reelfoot Lake, which is located near Tiptonville, Tennessee. The main shock occurred at 9:15 am, and its magnitude was estimated at 7.5. The US government did not provide victims of the destructive earthquakes with relief until the War of 1812 had ended. In 2011 the results of a report prepared by the USGS noted that residents within an area of approximately 232,000 square miles (about 600,000 square km) experienced very strong ground shaking, and people living in an area of roughly 965,000 square miles (about 2,500,000 square km) experienced shaking that was intense enough to frighten them. It appears here by permission of the author and the original publisher. Large waves formed on the water that capsized numerous boats and thrust others onto the land. He serves currently as the editor of Earth and life sciences, covering climatology, geology, zoology, and other topics that relate to... Map of the New Madrid earthquakes of 1811â12. Many geologists now believe the largest New Madrid quakes of 1811-12 were high 7 magnitude instead of 8's. See Magnitude - replaces Richter scale. Reports indicate that between December 1811 and March 1812, there were over 2000 earthquakes and aftershocks along the New Madrid fault. This region had 4 major 8.0+ magnitude earthquakes from December 1811-February 1812, during the Dalton Minimum (which included the âYear Without a Summerâ of 1816), as well as during other periods of intense seismic activity during solar grand minima. Despite the strength of the tremors, only minor damage to human-made structures was reported: from collapsing chimneys, falling trees, and cracking timbers in houses. 16 December 1811 (magnitude 7.5-7.9), epicenter in northeast Arkansas; 16 December 1811, aftershock (7.4), epicenter in northeast Arkansas. The relocated refugee Cherokee bands once again abandoned their farms, cattle, and property and headed farther west, where they encountered resistance from the nearby Osage population. He rushed on deck, where he and his anxious fellow passengers sought to determine the source of their peril. Magnitude estimates for each of the three events associated with the 1811â12 earthquake sequence vary widely, largely because they rely on historical accounts and analyses of the present-day landscape rather than data provided by modern seismic instrumentation. The 1811-1812 New Madrid earthquake sequence has been described in numerous ways: by Mitchell (1815) in terms of a series of disconnected historical vignettes, by Fuller (1912) in terms of far-field intensities and near-field geomorphic effects, by Nuttli (1973) anf magnitude, and by Johnston (1996c) in terms of seismic moment. âEarthquake Christiansâ who flocked to frontier revivals and swelled church membership rolls sometimes exhibited a curious amalgam of belief systems. The first earthquake was followed by 6 aftershocks in the range M5.5-6.3 in the first 2 days. At nearby Little Prairie the devastation was so severe that the entire population abandoned the town and headed northward, where the damage was rumored to have been less serious. The New Madrid Earthquakes. âSummary of 1811â1812 New Madrid Earthquakes Sequence.â https://earthquake.usgs.gov/earthquakes/events/1811-1812newmadrid/summary.php. Landslide trench and ridge in the Chickasaw Bluffs east of Reelfoot Lake, Tennessee, that resulted from the New Madrid earthquakes (1811â12). Get exclusive access to content from our 1768 First Edition with your subscription. They were among the most intense earthquakes in US history and by far the largest to occur east of the Rocky Mountains. Published March 13, 2020; Last updated March 19, 2020, Creative Commons Attribution-NonCommerical-ShareAlike 4.0 International (CC BY-NC-SA 4.0), The encyclopedia is freely provided with support from. Since the rocks in the eastern United States have few active faults to interrupt the propagation of seismic waves, ground vibrations from earthquakes generated in the region may travel thousands of miles. The frontier was not then California but the valley of the continent's greatest river, the Mississippi, and the sequence was the New Madrid earthquakes of the winter of 1811â1812. The January 23 event was the smallest of the three principal earthquakes. A number of earthquakes that happened near the town of New Madrid, in late 1811, and early 1812 are known as the 1811â12 New Madrid earthquakes today. Be on the lookout for your Britannica newsletter to get trusted stories delivered right to your inbox. Giant waves rose up and swept north, giving the impression that the river was actually flowing backwards. Attempts to link the bright and long-appearing comet of 1811 to the onset of the North American earthquakes were commonplace among Euro-American and Native American observers alike. When the nearly one hundred refugees reached New Madrid on Christmas Eve, they were dismayed to find its inhabitants camping in tents in open fields. Dear Sir: Since the area was sparsely populated there are few eye-witness accounts. River water disturbed by uplift and subsidence also washed out forested areas upstream. January 23, 1812, a magnitude 7.3 to 7.6 quake with an epicenter in the Missouri Bootheel struck at around 9:00 a.m. By signing up for this email, you are agreeing to news, offers, and information from Encyclopaedia Britannica. Penick, James Lal, Jr. Hancock, Jonathan Todd. The main shock that occurred at 2:15 am on December 16, 1811, was a result of slippage along the Cottonwood Grove Fault in northeastern Arkansas. James Madison is said to have felt the seismic waves arriving in Washington, D.C. Flatboat operators reported that the flow of the Mississippi River was suddenly reversed; however, scientific studies performed since that time note that the tremors produced northward-moving water waves that gave the illusion that the river reversed its course. When the quakes finally ended, the most adversely affected areas were in shambles: buildings collapsed, great fissures appeared in the earthâs surface, some land sank and other land uplifted, sand blows deposited subsurface sediment over large areas, rivers and streams altered their courses, the Mississippi briefly reversed its flow, large new lakes were formed, and entire forests were toppled. The â¦ Soil liquefaction caused large sand blows that fouled farmland in Missouri, Tennessee, and Arkansas. And far beyond, too: at magnitude 8.2 on the Richter scale, that earthquake reverberated over an area of more than 50,000 square miles, rattling windows as far away as Washington, D.C., and New Orleans. Over the years, estimates have placed the 1811-12 quakesâ magnitudes anywhere from under 7.0 to 8.5âan enormous range given that one additional unit â¦ Between December 16, 1811, and February 7, 1812, seven earthquakes of magnitude 6.0 to 7.5 on the Richter scale and numerous lesser aftershocks ravaged the affected area. The law limited such claimants to 640 acres of new land, and it prohibited them from relocating on mineral lands. of the 1811-1812 New Madrid earthquakes Susan E. Hough U.S. Geological Survey, Pasadena, California John G. Armbruster and Leonardo Seeber Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York Jerry F. Hough Department of Political Science, Duke University, Durham, North Carolina Abstract. Please read this article describing the 1811â1812 New Madrid earthquake sequence, then proceed with the rest of the lesson. It probably had a magnitude of 7.5-7.9 on the Richter scale. We reexamine original felt reports from the 1811-1812 New Madrid earthquakes â¦ Eyewitnesses reported that shaking from this temblor was severe, especially in New Bourbon, Missouri, but not as strong as the main shock. The epicentre of the aftershock is a matter of some debate; some Earth scientists noted that it was located in northeastern Arkansas, whereas others maintained that it was located in northwestern Tennessee near the southern end of the Reelfoot Fault, a large fault running northwest-southeast within the Reelfoot Rift. Although the relief measure had been designed to alleviate suffering in the devastated region, most Missourians believed that the lawâs principal beneficiaries had been the speculators. On land the impact of the earthquakes was no less horrific. The earthquakes and their aftershocks took place within a large region called the New Madrid Seismic Zone (NMSZ)âan area of high earthquake risk running from northeastern Arkansas and northwestern Tennessee to southeastern Missouri and southwestern Kentucky. The first earthquake of this series on December 16, 1811, was located in northeast Arkansas. Ground motions from the three principal events were felt in places as far away as Canada, New England, and the coast of South Carolina. By late spring the aftershocks had gradually diminished, but in the forlorn New Madrid district, only the hardiest souls remained. NEW MADRID EARTHQUAKE 1811-1812. Omissions? The Lost History of the New Madrid Earthquakes. Image credit: USGS. The active faults in the New Madrid Seismic Zone are difficult to assess because they are hidden beneath thick layers of soft river-deposited soils, but current US Geological Survey maps show it to be a high hazard zone comparable to those in California. Those initial tremors and the sporadic ones that followed for nearly two months reshaped the landscape, altered regional settlement patterns, and prompted unnerved residents to contemplate the mysterious forces of nature capable of wreaking so much havoc. In Louisville, Kentucky, a man who had homemade recording instruments reported a total of 1,874 shocks between December 11, 1811, and March 16, 1812. Magnitude: December 16, 1811: 2 A.M. 8.2: January 23, 1812: 8.1: February 7, 1812: 3:15 A.M. 8.3: The estimated locations of the epicenters of these earthquakes are shown below: Several towns, including New Madrid, shown on the above map were destroyed by the quakes. Our editors will review what youâve submitted and determine whether to revise the article. The temblors were felt far beyond New Madrid and its environs. Joseph Charless, the editor of the Missouri Gazette, momentarily thought that a volcanic eruption farther west might have been responsible for the clamor of windows, doors, and furniture in motion that interrupted his sleep. The waters of the Mississippi rose and fell like a great tide. Shortly after the earthquake began, ground shaking was felt as far away as Canada in the north and the Gulf Coast in the south. The location of this event is not well constrained, but the available accounts suggest an epicenter beyond the southern end of the New Madrid Seismic Zone. And finally, I have a letter Eliza Bryan wrote to Rev. In the spring of 1815, speculators poured into the New Madrid area seeking to purchase titles to damaged lands from unsuspecting residents before they learned about the new federal compensation law. The number of lives lost from the earthquakes remains unknown; however, scholars note that the number was probably not great, because the region had only a sparse rural population. All rights reserved. Some pursued the combative intertribal militancy favored by Tecumseh and the Shawnee Prophet Tenskwatawa, while others opted for more accommodationist strategies true to their own unique cultural frames of reference. In 1815, Congress belatedly authorized persons owning lands damaged by the New Madrid earthquakes to relocate at no charge on the same quantity of land on any US public lands available for sale. âA World Convulsed: Earthquakes, Authority and the Making of Nations in the War of 1812 Era.â PhD diss., University of North Carolina at Chapel Hill, 2013. Although no instrumental data are availa Amid the deafening din of crashing trees, collapsing riverbanks, and screaming wild birds, he sought to reassure the frightened crewmen eager to abandon the boat for the perceived safety of the shore. Between December 16, 1811, and February 7, 1812, seven earthquakes of magnitude 6.0 to 7.5 on the Richter scale and numerous lesser aftershocks ravaged the affected area. Structural damage also occurred in St. Louis, Missouri, where several chimneys fell because of the ground vibration. American evangelicals employed earthquakes as signs of Godâs wrath for sinful behavior and a catalyst for Christian conversion and repentance. They were among the most intense earthquakes in US history and by far the largest to occur east of the Rocky Mountains. In the known history of the world, no other earthquakes have lasted so long or produced so much evidence of damage as the New Madrid earthquakes. Corrections? Huge cracks split the ground. New Madrid earthquakes of 1811â12 - New Madrid earthquakes of 1811â12 - Possible causes of the New Madrid earthquakes: Over the past 4,500 years, a number of major earthquakes of magnitude 7.0 to 8.0 occurred in the NMSZ. The exodus of the areaâs inhabitants alarmed territorial secretary Frederick Bates, who worried that with all of the adverse publicity about earthquakes, Indians, and epidemics, Missouri would in a few years âbe nothing but a place of exile for Robbers & Outlaws.â Bates exhibited no such concern for Native Americans previously displaced from their eastern homelands and now forced to move for a second time to escape their suddenly uninhabitable lands along the St. Francis River. No appreciable damage to residences was reported; however, landscape changes, similar to those that occurred during the December 16 event, are thought to have taken place. A second earthquake of the same size hit six hours later, again shaking the ground more than 1,000 miles away. St. Louis, farther removed from the epicenter, escaped with only toppled chimneys and a few cracked stone and brick walls. A second series of tremors started on January 23, 1812, and the final and most severe set of shocks followed on February 7. The December 1811 earthquakes were merely a prelude to what lay ahead. https://earthquake.usgs.gov/earthquakes/events/1811-1812newmadrid/summary.php. Updates? As the largest settlement in the sparsely populated region, the Mississippi River town of New Madrid in southeast Missouri gave its name to the quakes and the seismic zone that generated them. There also was an aftershock of magnitude 7.4 on the same day. The Mississippi Valley Earthquakes of 1811 and 1812: Intensities, Ground Motion, and Magnitudes. On the Mississippi River itself, the shaking calved the soil along riverbanks and caused trees lining the river to fall into the water. Native people generally viewed the tremors as signs of the Great Spiritâs displeasure with their impure ways of living and the continuing American encroachment on their lands, but they chose to respond in widely divergent ways. Bulletin of the Seismological Society of America, 63(1), 227â248. Valencius, Conevery Bolton. Like the main shock, however, seismic waves from this event were also felt in cities along the Eastern Seaboard. Magnitude Estimates of Two Large Aftershocks of the 16 December 1811 New Madrid Earthquake. ed. These events include clusters of large earthquakes that have been dated to 2350 bce, 900 ce, and 1450 ce. Another local citizen echoed her sentiments: âwe were awakened by a most tremendous noise, while the house danced about and seemed as if it would fall on our heads.â As the earthquakes persisted, the river townâs terrified inhabitants fled their rolling and jostling homes and established encampments on higher ground to avoid the dangers of flooding. Columbia: University of Missouri Press, 1981. They argue that the three, possibly four, M7â8 New Madrid earthquake sequences prior to 1811â1812 that occurred in about A.D. 1450, A.D. 900, and A.D. 300 (Tuttle et al., 2002) were transient in nature, andthusconflictwiththemodelusedinstandardhazardcal- culations. Lorenzo Dow in 1816, describing the earthquake as eye-witness. Of greater importance is the resulting legislation, Bill No. Following is a short summary of the New Madrid Earthquakes that occurred between December 16, 1811 to February 7, 1812. The three principal New Madrid mainshocks of 1811-1812 were followed by extensive aftershock sequences that included numerous felt events. 69, passed by the 13th Session of Congress on February 25, 1814, â¦ Three of the earthquakes are on the list of America's top earthquakes: the first one on December 16, 1811, a magnitude of 8.1 on the Richter scale; the second on January 23, 1812, at 7.8; and the third on February 7, 1812, at as much as 8.8 magnitude. Third principal earthquake, on February 7, 1812 and February 7 however! Aftershock, a magnitude-7.0 tremor that became known as the âdawn aftershock, a magnitude-7.0 tremor became! To determine the source of their peril that day at 7:15 am present day the smallest the. As eye-witness US know if you have suggestions to improve this article ( requires )... Magnitude Estimates of two large aftershocks of the three principal earthquakes December earthquakes... 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