Earthquake light

Last updated

An earthquake light also known as earthquake lightning or earthquake flash is a luminous optical phenomenon that appears in the sky at or near areas of tectonic stress, seismic activity, or volcanic eruptions. [1] There is no broad consensus as to the causes of the phenomenon (or phenomena) involved. The phenomenon differs from disruptions to electrical grids – such as arcing power lines – which can produce bright flashes as a result of ground shaking or hazardous weather conditions. [2] [3] [4]

Contents

Appearance

One of the first records of earthquake lights is from the 869 Jōgan earthquake, described as "strange lights in the sky" in Nihon Sandai Jitsuroku. [5] The lights are reported to appear while an earthquake is occurring, although there are reports of lights before or after earthquakes, such as reports concerning the 1975 Kalapana earthquake. [6] They are reported to have shapes similar to those of the auroras, with a white to bluish hue, but occasionally they have been reported having a wider color spectrum. The luminosity is reported to be visible for several seconds, but has also been reported to last for tens of minutes. Accounts of viewable distance from the epicenter varies: in the 1930 Idu earthquake, lights were reported up to 110 km (70 mi) from the epicenter. [7] Earthquake lights were reportedly spotted in Tianshui, Gansu, approximately 400 km (250 mi) north-northeast of the 2008 Sichuan earthquake's epicenter. [8]

During the 2003 Colima earthquake in Mexico, colorful lights were seen in the skies for the duration of the earthquake.[ citation needed ] During the 2007 Peru earthquake lights were seen in the skies above the sea and filmed by many people. [9] The phenomenon was also observed and caught on film during the 2009 L'Aquila [10] [11] and the 2010 Chile earthquakes. [12] The phenomenon was also reported around the North Canterbury earthquake in New Zealand, that occurred 1 September 1888. The lights were visible in the morning of 1 September in Reefton, and again on 8 September. [13]

More recent appearances of the phenomenon, along with video footage of the incidents, happened in Napa and Sonoma Counties in California on August 24, 2014, [14] and in Wellington, New Zealand, on November 14, 2016, where blue flashes like lightning were seen in the night sky, and recorded on several videos. [15] On September 8, 2017, many people reported such sightings in Mexico City after a 8.2 magnitude earthquake with epicenter 740 km (460 mi) away, near Pijijiapan in the state of Chiapas. [16]

Appearances of the earthquake light seem to occur when the quakes have a high magnitude, generally 5 or higher on the Richter scale. [14] There have also been incidents of yellow, ball-shaped lights appearing before earthquakes. [17]

Instances of this phenomenon appear in videos [18] taken seconds after a 7.1 magnitude earthquake in the city of Acapulco, Mexico, around 20:47 on 7 September 2021. The New York Times reported that "Videos from both Acapulco and Mexico City also showed the night sky lit up with electrical flashes as power lines swayed and buckled." [19]

A recent one was seen in Qinghai Province, China at 01:45 on 8 January 2022. Surveillance video of a local resident captured the moment. During the 2022 Fukushima earthquake the phenomena was captured on video from multiple angles. [20] A 2023 study found the earthquake light coincided with a magnetic disturbance detected by a geomagnetic observatory, and ruled out "the possibility of the flashes being caused by explosions in transformers or power supply facilities" by checking the maintenance reports of regional power stations, none of which had malfunctioned near the location of the observed light. [21]

This phenomenon was observed around 01:18 on 22 September 2022 when a magnitude 6.8 aftershock of the 2022 Michoacán earthquake struck. Social media users including Webcams de México posted videos of blue lights which seemed to be radiating upward. This was reported in Mexico News Daily and included one of the videos. [22]

During the 2023 Turkey–Syria earthquakes, multiple lights appeared continuously in Kahramanmaraş and Hatay provinces. [23] Later that year, blue light flashes were also seen in Agadir during the Marrakesh-Safi earthquake. [24]

Types

Simplified model of phole propagation within an interplate, orogenic tectonic setting in a subduction zone environment (i.e., Andean-type). The vertical scale (topographic relief) is exaggerated for clarity. +, positive holes; e', electrons. How EQL form.gif
Simplified model of phole propagation within an interplate, orogenic tectonic setting in a subduction zone environment (i.e., Andean‐type). The vertical scale (topographic relief) is exaggerated for clarity. +, positive holes; e′, electrons.

Earthquake lights may be classified into two different groups based on their time of appearance: (1) preseismic earthquake light, which generally occur a few seconds to up to a few weeks prior to an earthquake, and are generally observed closer to the epicenter and (2) coseismic earthquake light, which can occur either near the epicenter ("earthquake‐induced stress"), or at significant distances away from the epicenter during the passage of the seismic wavetrain, in particular during the passage of S waves ("wave‐induced stress"). [25]

Earthquake light during the lower magnitude aftershock series seem to be rare. [25]

Possible explanations

Research into earthquake lights is ongoing; as such, several mechanisms have been proposed.

Some models suggest the generation of earthquake lights involve the ionization of oxygen to oxygen anions by breaking of peroxy bonds in some types of rocks (dolomite, rhyolite, etc.) by the high stress before and during an earthquake. [25] After the ionisation, the ions travel up through the cracks in the rocks. Once they reach the atmosphere these ions can ionise pockets of air, forming plasma that emits light. [26] Lab experiments have validated that some rocks do ionise the oxygen in them when subjected to high stress levels. Research suggests that the angle of the fault is related to the likelihood of earthquake light generation, with subvertical (nearly vertical) faults in rifting environments having the most incidences of earthquake lights. [27]

One hypothesis involves intense electric fields created piezoelectrically by tectonic movements of quartz-containing rocks such as granite. [28]

Another possible explanation is local disruption of the Earth's magnetic field and/or ionosphere in the region of tectonic stress, resulting in the observed glow effects either from ionospheric radiative recombination at lower altitudes and greater atmospheric pressure or as aurora. However, the effect is clearly not pronounced or notably observed at all earthquake events and is yet to be directly experimentally verified. [29]

During the American Physical Society's 2014 March meeting, research was provided that gave a possible explanation for the reason why bright lights sometimes appear during an earthquake. The research stated that when two layers of the same material rub against each other, voltage is generated. The researcher, Troy Shinbrot of Rutgers University, conducted experiments with different types of grains to mimic the crust of the Earth and emulated the occurrence of earthquakes. He reported that "when the grains split open, they measured a positive voltage spike, and when the split closed, a negative spike." The crack allows the voltage to discharge into the air which then electrifies the air and creates a bright electrical light when it does so. According to Shinbrot, they have produced these voltage spikes every single time with every material tested. While the reason for such an occurrence was not provided, Shinbrot referenced the phenomenon of triboluminescence. Researchers hope that by getting to the bottom of this phenomenon, it will provide more information that will allow seismologists to better predict earthquakes. [30] [31] [32]

Skepticism

In 2016, podcaster Brian Dunning said he was skeptical that the phenomenon even existed, citing a lack of direct evidence. There is also a "staggering volume of literature... hardly any of these papers agree on anything... I'm forced to wonder how many of these eager researchers are familiar with Hyman's Categorical Imperative 'Do not try to explain something until you are sure there is something to be explained'." [33]

In 2016, freelance writer Robert Sheaffer wrote that skeptics and science bloggers should be more skeptical of the phenomenon. Sheaffer on his Bad UFO blog shows examples of what people claim are earthquake lights, then he shows photos of iridescent clouds which appear to be the same. He states that "It's truly remarkable how mutable "earthquake lights" are. Sometimes they look like small globes, climbing up a mountain. Sometimes they look like flashes of lightning. Other times they look exactly like iridescent clouds. Earthquake lights can look like anything at all, when you are avidly seeking evidence for them." [34]

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">New Madrid seismic zone</span> Major seismic zone in the southern and midwestern United States

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

The Hessdalen lights are unidentified lights which have been observed in a 12-kilometre-long (7.5 mi) stretch of the Hessdalen valley in rural central Norway periodically since at least the 1930s.

The 1999 Hector Mine earthquake occurred in Southern California, United States, on October 16 at 02:46:50 PDT. Its moment magnitude was 7.1 and the earthquake was preceded by 12 foreshocks, the largest of which had a magnitude of 3.8. The event is thought to have been triggered by the 1992 Landers earthquake which occurred seven years earlier. It also deformed nearby faults vertically and horizontally. The earthquake's hypocenter was at a depth of 20 kilometers and its epicenter at 34.603° N 116.265° W.

The 2006 Gulf of Mexico earthquake occurred in the eastern Gulf of Mexico on September 10 at 10:56 AM Eastern Daylight Time. The intraplate earthquake measured 5.9 on the moment magnitude scale and its epicenter was located about 250 miles (400 km) west-southwest of Anna Maria, Florida. The event was felt throughout much of the Gulf Coast of the United States and was the second earthquake of magnitude 5 or greater in the Gulf during 2006. Felt intensities, as measured on the Mercalli intensity scale, were as high as IV (Light) in Florida, with parts of Georgia at III (Weak).

A cryoseism, ice quake or frost quake, is a seismic event caused by a sudden cracking action in frozen soil or rock saturated with water or ice, or by stresses generated at frozen lakes. As water drains into the ground, it may eventually freeze and expand under colder temperatures, putting stress on its surroundings. This stress builds up until relieved explosively in the form of a cryoseism. The requirements for a cryoseism to occur are numerous; therefore, accurate predictions are not entirely possible and may constitute a factor in structural design and engineering when constructing in an area historically known for such events. Speculation has been made between global warming and the frequency of cryoseisms.

A quake is the result when the surface of a planet, moon or star begins to shake, usually as the consequence of a sudden release of energy transmitted as seismic waves, and potentially with great violence. The types of quakes include earthquake, moonquake, marsquake, venusquake, sunquake, starquake, and mercuryquake. They can also all be referred to generically as earthquakes.

<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.

<span class="mw-page-title-main">2010 Baja California earthquake</span> Earthquake in Mexico

The 2010 Baja California earthquake occurred on April 4 with a moment magnitude of 7.2 and a maximum Mercalli intensity of VII. The shock originated at 15:40:41 local time south of Guadalupe Victoria, Baja California, Mexico.

The 2011 Guerrero earthquake struck with a moment magnitude of 5.7 in southern Mexico at 08:24 local time on 5 May. It was positioned west of Ometepec, Guerrero, with a focal depth of 24 km (14.9 mi), and was lightly felt in many adjacent areas.

<span class="mw-page-title-main">2007 Alderney UFO sighting</span> Reported UFO sighting

In the afternoon of 23 April 2007, Ray Bowyer, a pilot flying south towards the island of Alderney in the English Channel sighted unidentified flying objects. He reported the sighting to an air traffic controller who told him that a second pilot had seen something similar. In Bowyer's report to the British Civil Aviation Authority he said he saw two bright, stationary objects. Two passengers on Bowyer's aircraft said that they saw unusual coloured lights at the same time. Proposed explanations for the sighting have included earthquake lights and sun dogs.

The 2011 Kütahya earthquake struck near a populous region of western Turkey at 23:15 EEST (20:15 UTC) on 19 May with a moment magnitude of 5.8 and a maximum Mercalli intensity of VII. With an epicenter just to the east of Simav, it occurred at an estimated depth of 9.1 kilometers (5.7 mi), resulting in strong shaking in much of Kütahya.

<span class="mw-page-title-main">2011 Virginia earthquake</span> Earthquake in Virginia, U.S.

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.

<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.

The 2011 Zumpango earthquake occurred at 19:47 local time on 10 December with a moment magnitude of 6.5 and a maximum Mercalli intensity of VII. Its epicenter was located in the city Zumpango, Guerrero, roughly equidistant between the metropolitan areas of Mexico City and Acapulco. The quake was felt in Guerrero, Michoacán, Mexico State, Mexico City and Puebla.

The 2013 Saravan earthquake occurred with a moment magnitude of 7.7 at 15:14 pm IRDT (UTC+4:30) on 16 April. The shock struck a mountainous area between the cities of Saravan and Khash in Sistan and Baluchestan province, Iran, close to the border with Pakistan, with a duration of about 25 seconds. The earthquake occurred at an intermediate depth in the Arabian plate lithosphere, near the boundary between the subducting Arabian plate and the overriding Eurasian plate at a depth of about 80 km.

<span class="mw-page-title-main">2017 Puebla earthquake</span> Mw7.1 earthquake in Mexico

The 2017 Puebla earthquake, also known as 19S, struck at 13:14 CDT on 19 September 2017 with an estimated magnitude of 7.1 Mw and strong shaking for about 20 seconds. Its epicenter was about 55 km (34 mi) south of the city of Puebla, Mexico. The earthquake caused damage in the Mexican states of Puebla and Morelos and in the Greater Mexico City area, including the collapse of more than 40 buildings. 370 people were killed by the earthquake and related building collapses, including 228 in Mexico City, and more than 6,000 were injured.

An earthquake struck the Mexican state of Oaxaca at 10:29 local time on June 23, 2020, with a magnitude of 7.4 Mw. The epicenter was 19 miles (31 km) from San Miguel del Puerto and 7.5 miles (12.1 km) south-southwest of Santa María Zapotitlán. The quake was felt by an estimated 49 million people in Mexico and Guatemala, with some tremors felt as far away as 640 kilometers (400 mi). Thousands of houses in Oaxaca were damaged and 10 deaths were reported. A tsunami warning was issued for southern Mexico, El Salvador, Guatemala, and Honduras.

The 1968 Borrego Mountain earthquake occurred on April 8, at 18:28 PST in the geologically active Salton Trough of Southern California. The Salton Trough represents a pull-apart basin formed by movements along major faults. This region is dominated by major strike-slip faults one of them being the San Jacinto Fault which produced the 1968 earthquake. The mainshock's epicenter was near the unincorporated community of Ocotillo Wells in San Diego County. The moment magnitude (Mw ) 6.6 strike-slip earthquake struck with a focal depth of 11.1 km (6.9 mi). The zone of surface rupture was assigned a maximum Modified Mercalli intensity (MMI) of VII.

A moment magnitude Mw 7.0 or 7.1 earthquake occurred near the city of Acapulco in the Mexican state of Guerrero at 20:47 local time on 7 September with an estimated intensity of VIII (Severe) on the MMI scale. The earthquake killed 13 people and injured at least 23 others. At least 1.6 million people in Mexico were affected by the earthquake which resulted in localized severe damage. The earthquake occurred on the anniversary of the 2017 Chiapas earthquake which measured Mw 8.2. It was also the largest earthquake in Mexico since the 2020 Oaxaca earthquake.

References

  1. ↑ Whitehead, Neil Evan; Ulusoy, Ü. (17 December 2015). "Origin of Earthquake Light Associated with Earthquakes in Christchurch, New Zealand, 2010–2011" (PDF). Earth Sciences Research Journal. 19 (2): 113–120. doi:10.15446/esrj.v19n2.47000.
  2. ↑ "What are earthquake lights? | U.S. Geological Survey". United States Geological Survey. Retrieved 17 January 2023.
  3. ↑ Bressan, David. "'Light Shows' Filmed During Mexico Quake Are Neither Earthquake Lights Nor UFOs". Forbes. Retrieved 2023-01-17.
  4. ↑ "Power Flashes: Arcing power lines during storm events". stormhighway.com. Retrieved 2023-01-17.
  5. ↑ Clarke, Richard A.; Eddy, R. P. (2017). Warnings: Finding Cassandras to stop catastrophe. Harper Collins. p. 77.
  6. ↑ "November 29, 1975 Kalapana Earthquake". Hvo.wr.usgs.gov. Retrieved 2010-09-13.
  7. ↑ Lane, F. W. The Elements Rage (David & Charles 1966), pp. 175–76
  8. ↑ Paul Simons (2008-03-15). "Glowing lights around an earthquake's epicenter". The Times. London. Archived from the original on October 8, 2008. Retrieved 2008-05-20.
  9. ↑ "Study homes in on the cause of earthquake light". Physicsworld.com. 2014-01-14. Retrieved 2016-05-05.
  10. ↑ Fidani, C. (2010). "The earthquake lights (EQL) of the 6 April 2009 Aquila earthquake, in Central Italy". Natural Hazards and Earth System Sciences. 10 (5): 967–78. Bibcode:2010NHESS..10..967F. doi: 10.5194/nhess-10-967-2010 .
  11. ↑ Fidani, C. (March 2012). "Statistical and spectral properties of the L'Aquila EQL in 2009". Bollettino di Geofisica Teorica ed Applicata. 53 (1): 135–46. doi:10.4430/bgta0034. Archived from the original on 2015-05-19.
  12. ↑ "Registran enormes luces en el cielo durante terremoto de 88 grados de magnitud que destruyo Chile" [Recorded huge lights in the sky during the earthquake of 8.8 magnitude that destroyed Chile] (in Spanish). Peru Online. February 28, 2010. Archived from the original on March 1, 2010.
  13. ↑ Hutton (1888). "The Earthquake in the Aimuri". Transactions and Proceedings of the Royal Society of New Zealand. 21: 269–353.
  14. 1 2 Carter, Lori (25 August 2014). "Did you see flashes? Yep, an earthquake can create 'em (w/video)". Press Democrat. Press Democrat. Retrieved 9 September 2014.
  15. ↑ "Wellington's sky turns blue at midnight as quakes collide, produce rare tectonic plate phenomenon". 1News.co.nz. 1News. November 14, 2016. Retrieved August 15, 2022.
  16. ↑ "¿Qué eran las luces que se vieron durante el sismo?" [What were the lights that were seen during the earthquake?]. El Universal (in Spanish). Retrieved 8 September 2017.
  17. ↑ Howard, Brian Clark. "Bizarre Earthquake Lights Finally Explained". National Geographic . Archived from the original on January 9, 2014. Retrieved 25 August 2014.
  18. ↑ "Videos: Rare earthquake lights on Acapulco Mexico". Axency.com. 8 September 2021. Retrieved 13 September 2021.
  19. ↑ Lopez, Oscar (2021-09-08). "Major Quake Shakes Acapulco, Mexico City". The New York Times. ISSN   0362-4331 . Retrieved 2021-09-08.
  20. ↑ "'Earthquake light' appears in sky above Japanese city – video". The Guardian. 16 March 2022. Retrieved 7 May 2022.
  21. ↑ Xie, Busheng; Wu, Lixin; Mao, Wenfei; Wang, Ziqing; Sun, Licheng; Xu, Youyou (21 October 2023). "Horizontal Magnetic Anomaly Accompanying the Co-Seismic Earthquake Light of the M7.3 Fukushima Earthquake of 16 March 2022: Phenomenon and Mechanism". Remote Sensing . 15 (20): 5052. Bibcode:2023RemS...15.5052X. doi: 10.3390/rs15205052 . ISSN   2072-4292.
  22. ↑ Davies, Peter (2022-09-22). "6.9 magnitude earthquake rocks Michoacán; 2 deaths reported". Mexico News Daily. Retrieved 2022-09-23.
  23. ↑ "Dashcam footage captures moment fresh earthquake hits Turkey – video". The Guardian. 20 February 2023.
  24. ↑ "Mysterious blue light flashes moments before Morocco earthquake". Al Bawaba. 10 September 2023.
  25. 1 2 3 4 Thériault, Robert; St-Laurent, France; Freund, Friedemann T.; Derr, John S. (2014-01-01). "Prevalence of Earthquake Lights Associated with Rift Environments". Seismological Research Letters. 85 (1): 159–178. Bibcode:2014SeiRL..85..159T. doi:10.1785/0220130059. ISSN   0895-0695.
  26. ↑ Stromberg, Joseph (2014-01-02). "Why Do Lights Sometimes Appear in the Sky During An Earthquake?". Smithsonian Magazine. Retrieved 2021-10-11.
  27. ↑ Thériault, Robert; St-Laurent, France; Freund, Friedemann T.; Derr, John S. (2014). "Prevalence of Earthquake Lights Associated with Rift Environments". Seismological Research Letters. 85 (1). Seismological Society of America: 159–78. Bibcode:2014SeiRL..85..159T. doi:10.1785/0220130059. ISSN   0895-0695.
  28. ↑ Takaki, Shunji; Ikeya, Motoji (1998). "A Dark Discharge Model of Earthquake Lightning". Japanese Journal of Applied Physics. 37 (9A): 5016–20. Bibcode:1998JaJAP..37.5016T. doi:10.1143/JJAP.37.5016. S2CID   119878878.
  29. ↑ "'Restless Earth' May Give Advance Notice of Large Earthquakes" (Press release). NASA. December 7, 2001. Archived from the original on March 16, 2010. Retrieved January 4, 2014.
  30. ↑ Choi, Charles (26 February 2014). "Mysterious Flashing 'Earthquake Lights' Maybe Explained". livescience. Retrieved 9 September 2014.
  31. ↑ Kim, Meeri. "Experiments at Rutgers lend credence to existence of 'earthquake lights'". The Washington Post. Retrieved 9 September 2014.
  32. ↑ Luntz, Stephen (7 March 2014). "Clue To Mysterious Lights That Appear Before Earthquakes". Iflscience!. Retrieved 9 September 2014.
  33. ↑ Dunning, Brian. "Skeptoid #534: Earthquake Lights: Do They Exist?". Skeptoid . Retrieved 1 September 2016.
  34. ↑ Sheaffer, Robert (7 January 2014). "Skeptics and Claims of "Earthquake Lights"". Bad UFOs: Skepticism, UFOs, and The Universe. Blogger. Retrieved 6 September 2016.
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.