New Madrid seismic zone

Last updated

NMSZBig.gif
Reelfoot Rift and the New Madrid seismic zone in a 3D topographic image
NMSZ Erdbeben.jpg
Magnetic potential map of the Reelfoot Rift

The New Madrid seismic zone (NMSZ), sometimes called the New Madrid fault line (or fault zone or fault system), is a major seismic zone and a prolific source of intraplate earthquakes (earthquakes within a tectonic plate) in the Southern and Midwestern United States, stretching to the southwest from New Madrid, Missouri.

Contents

The New Madrid fault system was responsible for the 1811–1812 New Madrid earthquakes and has the potential to produce large earthquakes in the future. Since 1812, frequent smaller earthquakes have been recorded in the area. [1]

Earthquakes that occur in the New Madrid seismic zone potentially threaten parts of seven American states: Illinois, Missouri, Arkansas, Kentucky, Tennessee, and to a lesser extent Mississippi and Indiana. [2]

Location

The 150-mile (240 km)-long seismic zone, which extends into five states, stretches southward from Cairo, Illinois; through Hayti, Caruthersville, and New Madrid in Missouri; through Blytheville into Marked Tree in Arkansas. It also covers a part of West Tennessee near Reelfoot Lake, extending southeast into Dyersburg. It is southwest of the Wabash Valley seismic zone.

Geology

The geological structure of Reelfoot Rift, USGS, 1996 Reelfoot Rift diagram from USGS en.svg
The geological structure of Reelfoot Rift, USGS, 1996

The faults responsible for the NMSZ are embedded in a subsurface geological feature known as the Reelfoot Rift, which likely formed during the Cambrian Period. [3] The Reelfoot Rift was first described by Ervin and McGinnis (1975) and believed to be of late Precambrian age. [4] The rift failed to split the North American continent, but it has remained as an aulacogen (a scar or zone of weakness) deep underground. [3] [5]

This relative weakness is important, as it would allow the relatively small east–west compressive forces associated with the continuing westward continental drift of the North American plate to reactivate old faults around New Madrid, making the area unusually prone to earthquakes in spite of it being far from the nearest tectonic plate boundary. [6]

Since other ancient rifts are known to occur in North America, but not all are associated with modern earthquakes, other processes could be at work to locally increase mechanical stress on the New Madrid faults. [7] [8] Some form of heating in the lithosphere below the area has been suggested to be making deep rocks more plastic, which would concentrate compressive stress in the shallower subsurface area where the faulting occurs. [9] [10]

History

Earthquakes in the New Madrid and Wabash Valley seismic zones from 1974 to 2002, with magnitudes larger than 2.5 New Madrid and Wabash seizmic zones-USGS.png
Earthquakes in the New Madrid and Wabash Valley seismic zones from 1974 to 2002, with magnitudes larger than 2.5

The zone had four of the largest earthquakes in recorded North American history, with moment magnitudes estimated to be as large as 7 or greater, all occurring within a 3-month period between December 1811 and February 1812. Many of the published accounts describe the cumulative effects of all the earthquakes, known as the New Madrid Sequence, so finding the individual effects of each quake can be difficult. Magnitude estimates and epicenters are based on interpretations of historical accounts and may vary.

Prehistoric earthquakes

As uplift rates associated with large New Madrid earthquakes could not have occurred continuously over geological timescales without dramatically altering the local topography, studies have concluded that the seismic activity there cannot have gone on for longer than 64,000 years, making the New Madrid seismic zone a young feature, or that earthquakes and the associated uplift migrate around the area over time, or that the NMSZ has short periods of activity interspersed with long periods of dormancy. [11]

Archaeological studies have found from studies of sand blows and soil horizons that previous series of very large earthquakes have occurred in the NMSZ in recent prehistory. Based on artifacts found buried by sand blow deposits and from carbon-14 studies, previous large earthquakes like those of 1811–12 appear to have happened around AD 1450 and 900, [12] as well as around AD 300. Evidence has also been found for an apparent series of large earthquakes around 2350 BC. [13]

About 80 kilometres (50 mi) southwest of the presently defined NMSZ, but close enough to be associated with the Reelfoot Rift, near Marianna, Arkansas, two sets of liquefaction features indicative of large earthquakes have been tentatively identified and dated to 3500 and 4800 BC. These features were interpreted to have been caused by groups of large earthquakes timed closely together. [14]

Dendrochronology (tree ring) studies conducted on the oldest bald cypress trees growing in Reelfoot Lake found evidence of the 1811–12 series in the form of fractures followed by rapid growth after their inundation, whereas cores taken from old bald cypress trees in the St. Francis sunklands showed slowed growth in the half century that followed 1812. These were interpreted as clear signals of the 1811–12 earthquake series in tree rings. As the tree ring record in Reelfoot Lake and the St. Francis sunk lands extend back to 1682 and 1321, respectively, Van Arsdale et al. interpret the lack of similar signals elsewhere in the chronology as evidence against large New Madrid earthquakes between those years and 1811. [15]

December 25, 1699

The first known written record of an earthquake felt in the NMSZ was from a French missionary traveling up the Mississippi with a party of explorers. At 1 pm on Christmas Day 1699, at a site near the present-day location of Memphis, the party was startled by a short period of ground shaking. [16]

The Great Earthquake at New Madrid, a 19th-century woodcut from Devens' Our First Century (1877) New Madrid Erdbeben.jpg
The Great Earthquake at New Madrid, a 19th-century woodcut from Devens' Our First Century (1877)

1811–12 earthquake series

At New Madrid, trees were knocked down and riverbanks collapsed. This event shook windows and furniture in Washington, DC, rang bells in Richmond, Virginia, sloshed well water and shook houses in Charleston, South Carolina, and knocked plaster off of houses in Columbia, South Carolina. In Jefferson, Indiana, furniture moved, and in Lebanon, Ohio, residents fled their homes. Observers in Herculaneum, Missouri, called it "severe" and said it had a duration of 10–12 minutes. [21]
Aftershocks were felt every 6-10 minutes, a total of 27, in New Madrid until what was called the Daylight Shock, which was of the same intensity as the first. Many of these were also felt throughout the eastern US, though with less intensity than the initial earthquake. [21]
A map of more than 4,000 earthquakes in the area since 1974 New Madrid Seismic Zone activity 1974-2011.svg
A map of more than 4,000 earthquakes in the area since 1974

1812–1900

Hundreds of aftershocks of the 1811–12 series followed over a period of several years. Aftershocks strong enough to be felt occurred until 1817. The largest earthquakes to have occurred since then were on January 4, 1843, and October 31, 1895, with magnitude estimates of 6.0 and 6.6, respectively. The 1895 event had its epicenter near Charleston, Missouri. The quake damaged virtually all the buildings in Charleston, created sand volcanoes by the city, cracked a pier on the Cairo Rail Bridge, and toppled chimneys in St. Louis, Missouri; Memphis, Tennessee; Gadsden, Alabama; and Evansville, Indiana. [22]

Modern activity

The largest NMSZ earthquake of the 20th century was a 5.4-magnitude quake on November 9, 1968, near Dale, Illinois. The quake damaged the civic building at Henderson, Kentucky, and was felt in 23 states. People in Boston said their buildings swayed. At the time of the quake, it was the biggest recorded quake with an epicenter in Illinois in that state's recorded history. [23] In 2008 in the nearby Wabash Valley seismic zone, a similar magnitude 5.4 earthquake occurred with its epicenter in Illinois near West Salem and Mount Carmel.

Instruments were installed in and around the area in 1974 to closely monitor seismic activity. Since then, more than 4,000 earthquakes have been recorded, most of which were too small to be felt. On average, one earthquake per year is large enough to be felt in the area.

Potential for future earthquakes

In a report filed in November 2008, the U.S. Federal Emergency Management Agency warns that a serious earthquake in the NMSZ could result in "the highest economic losses due to a natural disaster in the United States," further predicting "widespread and catastrophic" damage across Alabama, Arkansas, Illinois, Indiana, Kansas, Kentucky, Mississippi, Missouri, Oklahoma, Texas, and particularly Tennessee, where a 7.7 magnitude quake would cause damage to tens of thousands of structures affecting water distribution, transportation systems, and other vital infrastructure. [24] The earthquake is expected to result in many thousands of fatalities, with more than 4,000 of the fatalities expected in Memphis alone.

The potential for the recurrence of large earthquakes and their effects today on densely populated cities in and around the seismic zone has generated much research devoted to understanding the NMSZ. By studying evidence of past quakes and closely monitoring ground motion and current earthquake activity, scientists attempt to understand their causes and recurrence intervals.

In October 2009, a team composed of University of Illinois and Virginia Tech researchers headed by Amr S. Elnashai, funded by the Federal Emergency Management Agency, considered a scenario where all three segments of the New Madrid fault ruptured simultaneously with a total earthquake magnitude of 7.7. The report found that there would be significant damage in the eight states studied – Alabama, Arkansas, Illinois, Indiana, Kentucky, Mississippi, Missouri, and Tennessee – with the probability of additional damage in states farther from the NMSZ. Tennessee, Arkansas, and Missouri would be most severely impacted, and Memphis and St. Louis would be severely damaged. The report estimated 86,000 casualties, including 3,500 fatalities, 715,000 damaged buildings, and 7.2 million people displaced, with two million of those seeking shelter, primarily due to the lack of utility services. Direct economic losses, according to the report, would be at least $300 billion. [25]

Iben Browning's 1990 prediction

Beginning in February 1989, self-proclaimed climatologist Iben Browning, who claimed to have predicted the 1980 eruption of Mount St. Helens and the 1989 Loma Prieta earthquake – predicted a 50% probability of a magnitude 6.5 to 7.5 earthquake in the New Madrid area sometime between December 1 and December 5, 1990. [26] [27] Browning appears to have based this prediction on particularly strong tidal forces being expected during that time, and his opinion that a New Madrid earthquake was "overdue;" however, seismologists generally agree that no correlation exists between tides and earthquakes. [27]

The United States Geological Survey (USGS) requested an evaluation of the prediction by an advisory board of earth scientists, who concluded, "the prediction does not have scientific validity." [27] Despite the lack of scientific support, Browning's prediction was widely reported in international media, causing public alarm. The period passed with no major earthquake activity in New Madrid or along the 120-mile (190 km) fault line. [27]

Uncertainty over recurrence potential

The lack of apparent land movement along the New Madrid fault system has long puzzled scientists. In 2009, two studies based on eight years of GPS measurements indicated that the faults were moving at no more than 0.2 mm (0.008 in.) per year. [28] This contrasts to the rate of slip on the San Andreas Fault, which averages up to 37 mm (1.5 in) per year across California. [29]

On March 13, 2009, a research group based out of Northwestern University and Purdue University, funded by the USGS, reported in Science and other journals that the New Madrid system may be "shutting down" and that tectonic stress may now be accumulating elsewhere. [28] Seth Stein, the leader of the research group, published these views in a book, Disaster Deferred, in 2008. Although some of these ideas have gained some acceptance among researchers, they have not been accepted by the National Earthquake Prediction Evaluation Council, which advises the USGS. [30] In the November 5, 2009, issue of Nature , researchers from Northwestern University and the University of Missouri said that due to the lack of fault movement, the quakes along the faults may only be aftershocks of the 1811–12 earthquakes. [31]

According to the USGS, a broad consensus exists that the possibility of major earthquakes in the NMSZ remains a concern, and that the GPS data do not provide a compelling case for lessening perceived earthquake hazards in the region. One concern is that the small earthquakes that still happen are not diminishing over time, as would be if they were aftershocks of the 1811–12 events; another is that the 4,500-year archaeological record of large earthquakes in the region is more significant than 10 years of direct strain measurement. The USGS issued a fact sheet in 2009 stating the estimate of a 7–10% chance of a New Madrid earthquake of magnitude comparable to one of the 1811–12 quakes within the next 50 years, and a 25–40% chance of a magnitude 6 earthquake in the same time frame. [32] In July 2014, the USGS increased the risk assessment for the New Madrid area. [33]

See also

Related Research Articles

<span class="mw-page-title-main">Earthquake</span> Sudden movement of the Earths crust

An earthquake – also called a quake, tremor, or temblor – is the shaking of the Earth's surface resulting from a sudden release of energy in the lithosphere that creates seismic waves. Earthquakes can range in intensity, from those so weak they cannot be felt, to those violent enough to propel objects and people into the air, damage critical infrastructure, and wreak destruction across entire cities. The seismic activity of an area is the frequency, type, and size of earthquakes experienced over a particular time. The seismicity at a particular location in the Earth is the average rate of seismic energy release per unit volume.

<span class="mw-page-title-main">Epicenter</span> Point on the Earths surface that is directly above the hypocentre or focus in an earthquake

The epicenter, epicentre, or epicentrum in seismology is the point on the Earth's surface directly above a hypocenter or focus, the point where an earthquake or an underground explosion originates.

<span class="mw-page-title-main">Intraplate earthquake</span> Earthquake that occurs within the interior of a tectonic plate

An intraplate earthquake occurs in the interior of a tectonic plate, in contrast to an interplate earthquake on the boundary of a tectonic plate. They are relatively rare compared to the more familiar interplate earthquakes. Buildings far from plate boundaries are rarely protected with seismic retrofitting, so large intraplate earthquakes can inflict heavy damage. Examples of damaging intraplate earthquakes are the devastating 2001 Gujarat earthquake, the 2011 Christchurch earthquake, the 2012 Indian Ocean earthquakes, the 2017 Puebla earthquake, the 1811–1812 New Madrid earthquakes, and the 1886 Charleston earthquake. An earthquake that occurs within a subducting plate is known as an intraslab earthquake.

<span class="mw-page-title-main">1811–1812 New Madrid earthquakes</span> Series of earthquakes during 1811-1812 impacting on Missouri USA

The 1811–1812 New Madrid earthquakes were a series of intense intraplate earthquakes beginning with an initial earthquake of moment magnitude 7.2–8.2 on December 16, 1811, followed by a moment magnitude 7.4 aftershock on the same day. Two additional earthquakes of similar magnitude followed in January and February 1812. They remain the most powerful earthquakes to hit the contiguous United States east of the Rocky Mountains in recorded history. The earthquakes, as well as the seismic zone of their occurrence, were named for the Mississippi River town of New Madrid, then part of the Louisiana Territory and now within the U.S. state of Missouri.

<span class="mw-page-title-main">Mississippi embayment</span> Low-lying basin filled with Cretaceous to recent sediments

The Mississippi embayment is a physiographic feature in the south-central United States, part of the Mississippi Alluvial Plain. It is essentially a northward continuation of the fluvial sediments of the Mississippi River Delta to its confluence with the Ohio River at Cairo, Illinois. The current sedimentary area was formed in the Cretaceous and early Cenozoic by the filling with sediment of a pre-existing basin. An explanation for the embayment's formation was put forward by Van Arsdale and Cox in 2007: movement of the Earth's crust brought this region over a volcanic "hotspot" in the Earth's mantle causing an upthrust of magma which formed the Appalachian-Ouachita range. Subsequent erosion caused a deep trough that was flooded by the Gulf of Mexico and eventually filled with sediment from the Mississippi River.

The Virginia seismic zones in the U.S. state of Virginia include the Giles County seismic zone and the Central Virginia seismic zone. Earthquakes in the state are irregular and rarely reach over 4.5 in magnitude.

<span class="mw-page-title-main">Wabash Valley seismic zone</span> Tectonic region in the Midwestern United States

The Wabash Valley seismic zone is a tectonic region located in the Midwestern United States, centered on the valley of the lower Wabash River, along the state line between southeastern Illinois and southwestern Indiana.

The 1998 Pymatuning earthquake occurred in the U.S. state of Pennsylvania on September 25 at 19:52 UTC. With a magnitude of 5.2 mbLg, it was the largest recorded earthquake in Pennsylvania's history.

<span class="mw-page-title-main">1931 Valentine earthquake</span> Most powerful earthquake in Texas history

In the early morning hours of August 16, 1931, a powerful earthquake occurred in West Texas with a maximum Mercalli intensity of VIII (Severe). Estimates of its magnitude range between 5.8 and 6.4 mb, making it the most powerful earthquake ever recorded in Texas history. Its epicenter was near the town of Valentine, Texas; there, the earthquake caused damage to many homes and buildings. The earthquake may have been caused by movement along oblique-slip faulting in West Texas, the most seismically active region in the state. Shaking from the earthquake was perceptible within a 400 mi (640 km) radius of the epicenter, affecting four U.S. states and northern Mexico. Several foreshocks and aftershocks accompanied the primary temblor, with the aftershocks continuing until at least November 3, 1931. The main earthquake caused no fatalities, though several people sustained minor injuries; the damage in Valentine amounted to $50,000–$75,000.

<span class="mw-page-title-main">Ramapo Fault</span> System of faults in the northeast United States

The Ramapo Fault zone is a system of faults between the northern Appalachian Mountains and Piedmont areas to the east. Spanning more than 185 miles (298 km) in New York, New Jersey, and Pennsylvania, it is perhaps the best known fault zone in the Mid-Atlantic region, and some small earthquakes have been known to occur in its vicinity. Recently, public knowledge about the fault has increased, especially after the 1970s, when the fault's proximity to the Indian Point nuclear plant in New York was noted.

<span class="mw-page-title-main">1968 Illinois earthquake</span> Largest recorded earthquake in Illinois, US

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 1867 Manhattan earthquake struck Riley County, Kansas, in the United States on April 24, 1867, at 20:22 UTC, or about 14:30 local time. The strongest earthquake to originate in the state, it measured 5.1 on a seismic scale that is based on an isoseismal map or the event's felt area. The earthquake's epicenter was near the town of Manhattan.

<span class="mw-page-title-main">1916 Irondale earthquake</span> Earthquake in Alabama on October 18, 1916

The 1916 Irondale earthquake struck in the north-central region of the U.S. state of Alabama on October 18. The strongest earthquake in state history, it registered an estimated Richter scale magnitude of 5.1 and resulted in minor damage. Damage was limited to Shelby and Jefferson counties and reached its maximum severity near the epicenter in the city of Irondale, including cracked windows, fallen chimneys, and dried-up wells. While there were no fatalities, the earthquake spawned widespread panic, prompting alarmed workers to evacuate tall buildings.

<span class="mw-page-title-main">2011 Oklahoma earthquake</span> 2011 earthquake near Prague, Oklahoma

The 2011 Oklahoma earthquake was a 5.7 magnitude intraplate earthquake which occurred near Prague, Oklahoma on November 5 at 10:53 p.m. CDT in the U.S. state of Oklahoma. The epicenter of the earthquake was in the vicinity of several active wastewater injection wells. According to the United States Geological Survey (USGS), it was the most powerful earthquake ever recorded in Oklahoma until the 2016 Oklahoma earthquake. The previous record was a 5.5 magnitude earthquake that struck near the town of El Reno in 1952. The quake's epicenter was approximately 44 miles (71 km) east-northeast of Oklahoma City, near the town of Sparks and was felt in the neighboring states of Texas, Arkansas, Kansas and Missouri and even as far away as Tennessee and Wisconsin. The quake followed several minor quakes earlier in the day, including a 4.7 magnitude foreshock. The quake had a maximum perceived intensity of VIII (Severe) on the Mercalli intensity scale in the area closest to the epicenter. Numerous aftershocks were detected after the main quake, with a few registering at 4.0 magnitude.

<span class="mw-page-title-main">Oklahoma earthquake swarms (2009–present)</span> Series of earthquakes in central Oklahoma, southern Kansas, and northern Texas

The Oklahoma earthquake swarms are an ongoing series of human activity-induced earthquakes affecting central Oklahoma, southern Kansas, northern Texas since 2009. Beginning in 2009, the frequency of earthquakes in the U.S. state of Oklahoma rapidly increased from an average of fewer than two 3.0+ magnitude earthquakes per year since 1978 to hundreds each year in the 2014–17 period. Thousands of earthquakes have occurred in Oklahoma and surrounding areas in southern Kansas and North Texas since 2009. Scientific studies attribute the rise in earthquakes to the disposal of wastewater produced during oil extraction that has been injected more deeply into the ground.

<span class="mw-page-title-main">2018 Hawaii earthquake</span> 6.9-magnitude earthquake in Hawaii

On May 4, 2018, an earthquake with a magnitude of Mw 6.9 struck Hawaii island in the Hawaii archipelago at around 12:33 p.m. local time. The earthquake's epicenter was near the south flank of Kīlauea, which has been the site of seismic and volcanic activity since late April of that year. According to the United States Geological Survey the quake was related to the new lava outbreaks at the volcano, and it resulted in the Hilina Slump moving about two feet. It was the largest earthquake to affect Hawaii since the 1975 earthquake, which affected the same region, killing two people and injuring another 28.

<span class="mw-page-title-main">2021 Chignik earthquake</span> 7th largest earthquake in the US

An earthquake occurred off the coast of the Alaska Peninsula on July 28, 2021, at 10:15 p.m. local time. The large megathrust earthquake had a moment magnitude of 8.2 according to the United States Geological Survey (USGS). A tsunami warning was issued by the National Oceanic and Atmospheric Administration (NOAA) but later cancelled. The mainshock was followed by a number of aftershocks, including three that were of magnitude 5.9, 6.1 and 6.9 respectively.

The 1870 Charlevoix earthquake occurred on 20 October in the Canadian province of Quebec. It had a moment magnitude of 6.6 Mw  and a Modified Mercalli intensity rating of X (Extreme). The town of Baie-Saint-Paul was seriously damaged by the event, with the loss of six lives. Effects from the earthquake were felt as far as Virginia and along the New England coast of the United States.

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.

References

  1. ↑ "Center for Earthquake Research and Information at the University of Memphis". University of Memphis.
  2. ↑ Stelzer, C. D. (December 15, 1999). "On Shaky Ground". Riverfront Times. Retrieved October 16, 2017.
  3. 1 2 Csontos, Ryan; Van Arsdale, Roy; Waldron, Brian (2008). "Reelfoot rift and its impact on Quaternary deformation in the central Mississippi River valley". Geosphere. 4 (1): 145–158. Bibcode:2008Geosp...4..145C. doi: 10.1130/GES00107.1 .
  4. ↑ Ervin, C. Patrick; McGinnis, L. D. (1975). "Reelfoot Rift: Reactivated Precursor to the Mississippi Embayment". GSA Bulletin. 86 (9): 1287–1295. Bibcode:1975GSAB...86.1287E. doi:10.1130/0016-7606(1975)86<1287:RRRPTT>2.0.CO;2 . Retrieved October 22, 2021.
  5. ↑ Hildenbrand, Thomas G.; Langenheim, Victoria E.; Schweig, Eugene; Stauffer, Peter H.; Hendley II, James W. (1996). "Uncovering Hidden Hazards in the Mississippi Valley" (PDF). U.S. Geological Survey Fact Sheet 200-96. United States Geological Survey. Retrieved October 22, 2021.
  6. ↑ "USGS Earthquake Hazards Program, Earthquake Report: Kentucky". National Earthquake Information Center. June 6, 2003. Archived from the original on April 20, 2006.
  7. ↑ Grollimund, Balz; Zoback, Mark D. (February 2001). "Did deglaciation trigger intraplate seismicity in the New Madrid seismic zone?". Geology. 29 (2): 175–178. Bibcode:2001Geo....29..175G. doi:10.1130/0091-7613(2001)029<0175:DDTISI>2.0.CO;2.
  8. ↑ Pollitz, Fred F.; Kellogg, Louise; Bürgmann, Roland (December 2001). "Sinking Mafic Body in a Reactivated Lower Crust: A Mechanism for Stress Concentration at the New Madrid Seismic Zone". Bulletin of the Seismological Society of America. 91 (6): 1882–1897. Bibcode:2001BuSSA..91.1882P. doi:10.1785/0120000277.
  9. ↑ Liu, L.; Zoback, M. D. (1997). "Lithospheric strength and intraplate seismicity in the New Madrid seismic zone". Tectonics. 16 (4): 585–595. Bibcode:1997Tecto..16..585L. doi:10.1029/97TC01467. S2CID   129287433.
  10. ↑ Forte, A. M.; Mitrovica, J. X.; R. Moucha; N. A. Simmons; S. P. Grand (2007). "Descent of the ancient Farallon slab drives localized mantle flow below the New Madrid seismic zone" (PDF). Geophys. Res. Lett. 34 (4): L04308. Bibcode:2007GeoRL..34.4308F. doi:10.1029/2006GL027895. S2CID   10662775. Archived from the original (PDF) on July 6, 2011.
  11. ↑ Pratt, Thomas L (April–June 1994). "How old is the New Madrid Seismic Zone?" (PDF). Seismological Research Letters. 65 (2): 172–179. Bibcode:1994SeiRL..65..172P. doi:10.1785/gssrl.65.2.172. Archived from the original (PDF) on December 10, 2013.
  12. ↑ Tuttle, Martitia P.; Schweig, Eugene S.; John D. Sims; Lafferty, Robert H.; Wolf, Lorraine W.; Hayes, Marion L. (August 2002). "The Earthquake Potential of the New Madrid Seismic Zone". Bulletin of the Seismological Society of America. 92 (6): 2080–2089. Bibcode:2002BuSSA..92.2080T. doi:10.1785/0120010227.
  13. ↑ Tuttle, Martitia P.; Schweig, III, Eugene S.; et al. (July–August 2005). "Evidence for New Madrid Earthquakes in A.D. 300 and 2350 B.C". Seismological Research Letters. 76 (4): 489–501. Bibcode:2005SeiRL..76..489T. doi:10.1785/gssrl.76.4.489.
  14. ↑ Tuttle, MP; Al-Shukri, H; Mahdi, H (2006). "Very Large Earthquakes Centered Southwest of the New Madrid Seismic Zone 5,000–7,000 Years Ago". Seismological Research Letters. 77 (6): 755. Bibcode:2006SeiRL..77..755T. doi:10.1785/gssrl.77.6.755.
  15. ↑ Van Arsdale, RB; Stahle, DW; MK Cleaveland; MJ Guccione (June 1998). "Earthquake signals in tree-ring data from the New Madrid seismic zone and implications for paleoseismicity". Geology. 26 (6): 515–518. Bibcode:1998Geo....26..515V. doi:10.1130/0091-7613(1998)026<0515:ESITRD>2.3.CO;2.
  16. ↑ Feldman, Jay (2005). When the Mississippi Ran Backwards : Empire, Intrigue, Murder, and the New Madrid Earthquakes. Free Press. ISBN   978-0-7432-4278-3.
  17. 1 2 3 4 5 6 "Summary of 1811-1812 New Madrid Earthquakes Sequence". Earthquake Hazards Program. United States Geological Survey. Archived from the original on September 8, 2017. Retrieved September 8, 2017.
  18. 1 2 3 4 "Report of the Independent Expert Panel on New Madrid Seismic Zone Earthquake Hazards" (PDF). United States Geological Survey. Archived from the original (PDF) on September 8, 2017. Retrieved September 8, 2017.
  19. 1 2 3 Johnston & Schweig, A. C, E. S (1996). "The Enigma of the New Madrid Earthquakes of 1811-1812". Annual Review of Earth and Planetary Sciences. 24: 339–384. Bibcode:1996AREPS..24..339J. doi:10.1146/annurev.earth.24.1.339. S2CID   16780063.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  20. ↑ "Historic Earthquakes". Earthquake Hazards Program. United States Geological Survey. Archived from the original on July 12, 2012.
  21. 1 2 Fuller, Myron (1912), The New Madrid Earthquake (PDF), United States Geological Survey
  22. ↑ "Historic Earthquakes: Near Charleston, Mississippi County, Missouri". United States Geological Survey. Archived from the original on July 7, 2012. Retrieved September 23, 2009.
  23. ↑ "Historic Quakes: Southern Illinois 1968 11 09 17:01:40.5 UTC". United States Geological Survey. Archived from the original on July 8, 2012. Retrieved September 23, 2009.
  24. ↑ "Government warns of "catastrophic" U.S. quake". Reuters. November 20, 2008. Retrieved October 16, 2017.
  25. ↑ "Impact of New Madrid Seismic Zone Earthquakes on the Central USA" Mid-American Earthquake Center Report 09-03. Urbana, IL: Mid-America Earthquake Center. University of Illinois at Urbana-Champaign.
  26. ↑ Fowler, Glenn (July 20, 1991). "Iben Browning, 73; Researcher Studied Climate and Quakes". The New York Times. Retrieved July 2, 2011.
  27. 1 2 3 4 Spence, William J.; Herrmann, R. B.; Johnston, A. C.; Reagor, B. G. (1993). "Responses to Iben Browning's Prediction of a 1990 New Madrid, Missouri, Earthquake". Dept. of the Interior, U.S. Geological Survey. Archived from the original on April 18, 2015. Retrieved July 22, 2011.
  28. 1 2 Gardner, Elizabeth K. (2009). "New Madrid fault system may be shutting down" . Retrieved October 16, 2017.
  29. ↑ Thatcher, Wayne "Present-Day Crustal Movements and the Mechanics of Cyclic Deformation" in "The San Andreas Fault System, California." USGS Professional Paper 1515. Robert E. Wallace, editor. 1990. Retrieved December 6, 2013.
  30. ↑ Monastersky, Richard. "Nature News: Seth Stein: The Quake Killer" Nature (9 November 2011)
  31. ↑ "Earthquakes Actually Aftershocks Of 19th Century Quakes; Repercussions Of 1811 And 1812 New Madrid Quakes Continue To Be Felt". Science Daily . Retrieved November 4, 2009.
  32. ↑ Earthquake Hazard in the New Madrid Seismic Zone Remains a Concern USGS (2009). Retrieved 12/6/13
  33. ↑ Petersen, Mark D.; Moschetti, Morgan P.'; Powers, Peter M.' et al. (July 17, 2014) "Documentation for the 2014 Update of the United States National Seismic Hazard Maps" United States Geological Survey

Further reading

36°35′N89°35′W / 36.58°N 89.59°W / 36.58; -89.59

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.