Pre-earthquake signals: Underlying physical processes

Freund, Friedemann

doi:10.1016/j.jseaes.2010.03.009

Cited by 244 publications

(172 citation statements)

References 138 publications

(169 reference statements)

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“…In contrast, normal levels of radon in cities caused through common atmospheric meteorological inversions are about 10 times higher than those likely from earthquakes (Ikeya and Whitehead, 2013). Different analytical treatment, (Freund, 2011) also concludes radon is not a factor in EQL. Thus, although ionizing events are occurring, the radiation dose is not critical.…”

Section: Radiation Dose?mentioning

confidence: 97%

“…It is calculated that this creates an intense positive electric field at the surface, air breakdown/positive ionization, then dissipation of the charge (e.g. Freund (2011) and references therein). The recombination could give rise to the blue/white flashes observed, and UV.…”

Section: Mechanismsmentioning

confidence: 99%

“…Most show a white spherical ground-based core surrounded by radiating blue-white light, fading the further it is from the core. There are now thought to be numerous valid records throughout history (Derr, 1973), (Stothers, 2004), (Thériault, St-Laurent, Freund, and Derr, 2014), though the origin is still argued, (Straser, 2007), (Fidani, 2010), (Fidani, 2012), (Freund, 2011), and may be multiple.…”

Section: Introductionmentioning

confidence: 99%

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Origin of Earthquake Light Associated with Earthquakes in Christchurch, New Zealand, 2010-2011

Whitehead

Ulusoy

2015

Earth sci. res. j.

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Earthquake light (EQL) mainly blue-white flashes from the ground, was observed coseismically during a New Zealand M7.1 earthquake, (4.47 am 4-Sep-2010 local time). A local production mechanism is most probable. The blue-white flash observations support the Freund et al. mechanism, i.e. shockwave disturbance creating electronic "holes" from ruptured peroxy bonds in quartz, and subsequent surface positive charge from the ground, followed by light emission during neutralization. Examination of video records shows the flash median length is about half a second and needs to be differentiated from the light during electricity supply short circuits. Observed ground-level white colors appear to result from very intense non-specific air ionization. Blue colors seem to be nitrogen emission with a short lifetime, succeeded by green oxygen emissions with longer lifetime followed by much lower intensity red. These were created by transient low-to-moderate voltages and probably include significant UV production. The maximum likely radiation dose is small, restricted to the skin, and equivalent at most to a few months natural background radiation. Calculations confirm the release of 222 Rn is not the major mechanism for creating earthquake light, and would contribute minimal radiation dose. Other unique observations are: streamers of light changing from blue to green as they passed from west to east, vertical sheets of blue-green light from cracks in an asphalt road surface, created by local shockwaves and shearing forces, daylight observation by fishermen of rapid linear undersea travel of blue light seconds before a 2011 M6.0 aftershock, and a mid-day green-blue glow over nearby hills containing a fault zone, shortly before the further destructive M6.3 earthquake, (12.51 pm 22-Feb-2011).Las luces de terremoto o EQL (del inglés "Earth Quake Light") son principalmente azul blancas y fueron cosísmicamente observadas durante un terremoto de magnitud 7.1 en Nueva Zelanda (4:47 a.m., 4 de septiembre de 2010, hora local). Es muy probable que el fenómeno haya sido producto de un mecanismo local. Las observaciones del destello azul blanco coinciden con el mecanismo de Freund y otros, esto es, la alteración de un movimiento sísmico que crea "agujeros" electrónicos a partir de lazos de ácido peroxi rotos en cuarzos, con carga positiva superficial consecuente del suelo, y seguida por la emisión de luz durante la neutralización. La revisión de grabaciones de video muestra que la duración del destello es de cerca de medio segundo y debe ser diferenciado de la luz generada por los cortos circuitos del fluido eléctrico. Los colores blancos observados a nivel del terreno parecen resultar de una intensa ionización aérea no específica. Los colores azules serían emisiones de nitrógeno con un corto período de duración, sucedidas por emisiones de oxígeno verde de mayor duración y seguidas por un rojo mucho menos intenso. Estos colores fueron creados por voltajes transitorios de bajo a moderados y probablemente incluyen una producción significativ...

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Section: Radiation Dose?mentioning

confidence: 97%

Section: Mechanismsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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Origin of Earthquake Light Associated with Earthquakes in Christchurch, New Zealand, 2010-2011

Whitehead

Ulusoy

2015

Earth sci. res. j.

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“…With the development of Earth observation technologies and anomaly recognition methods (e.g., Wu et al, 2012;Qin et al, 2013), non-thermal anomalous variations in geochemical and electromagnetic signals from different spheres of the planet Earth may indicate complex geosphere coupling effects during the slow preparation phase of earthquakes. During the past decades, several mechanisms or hypotheses for interpreting thermal anomalies have been proposed; examples include the positive hole (P-hole) effect (Freund, 2011), transient electric field (Liperovsky et al, 2008a), frictional heat of faults (Geng et al, 1998;Wu et al, 2006), and the greenhouse effect caused by Earth degassing (Tronin et al, 2002). A unified lithosphere-atmosphere-ionosphere coupling (LAIC) model was proposed to explain the inherent links among different parameters (Liperovsky et al, 2008b;Pulinets and Ouzounov, 2011;Pulinets, 2012).…”

Section: Introductionmentioning

confidence: 99%

Geosphere coupling and hydrothermal anomalies before the 2009 <i>M</i><sub>w</sub> 6.3 L'Aquila earthquake in Italy

Zheng

Santis

et al. 2016

Nat. Hazards Earth Syst. Sci.

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Abstract. The earthquake anomalies associated with the 6 April 2009 M w 6.3 L'Aquila earthquake have been widely reported. Nevertheless, the reported anomalies have not been so far synergically analyzed to interpret or prove the potential lithosphere-coversphere-atmosphere coupling (LCAC) process. Previous studies on b value (a seismicity parameter from Gutenberg-Richter law) are also insufficient. In this work, the spatiotemporal evolution of several hydrothermal parameters related to the coversphere and atmosphere, including soil moisture, soil temperature, near-surface air temperature, and precipitable water, was comprehensively investigated. Air temperature and atmospheric aerosol were also statistically analyzed in time series with ground observations. An abnormal enhancement of aerosol occurred on 30 March 2009 and thus proved quasi-synchronous anomalies among the hydrothermal parameters from 29 to 31 March in particular places geo-related to tectonic thrusts and local topography. The three-dimensional (3-D) visualization analysis of b value revealed that regional stress accumulated to a high level, particularly in the L'Aquila basin and around regional large thrusts. Finally, the coupling effects of geospheres were discussed, and a conceptual LCAC mode was proposed to interpret the possible mechanisms of the multiple quasi-synchronous anomalies preceding the L'Aquila earthquake. Results indicate that CO 2 -rich fluids in deep crust might have played a significant role in the local LCAC process.

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“…For example, special ionizers were tested that employ the stimulation of plants placed in a salt solution with high electric voltage [20], and their influence and effect on the tracheas of laboratory (sewer-) rats were evaluated, together with an analysis of the state of their blood. Measuring the concentration of air ions is widely applied in monitoring the degree of air pollution, hygiene checks at workplaces, health therapy -speleotherapy [21]- [23], in the study of electric phenomena in the atmosphere and, topically, in forecasting earthquakes [24], [25] or other weather anomalies. Aplin [26] describes the effects of atmospheric electricity on its surroundings and the manner it is generated in the troposphere.…”

Section: Introductionmentioning

confidence: 99%

Measuring Light Air Ions in a Speleotherapeutic Cave

Roubal

Bartušek

Szabó

et al. 2017

Measurement Science Review

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The paper deals with a methodology proposed for measuring the concentration of air ions in the environment of speleotherapeutic caves, and with the implementation of the AK-UTEE-v2 ionmeter. Speleotherapy, in the context of its general definition, is the medical therapy that utilizes the climate of selected caves to treat patients with health problems such as asthma. These spaces are characterized by the presence of high air humidity and they make extreme demands on the execution of the measuring device, the Gerdien tube (GT in the following) in particular, and on the amplifier electronics. The result is an automated measuring system using a GT with low-volume air flow, enabling long-term measuring of air ion concentration and determination of spectral ion characteristics. Interesting from the instrumentation viewpoint are the GT design, active shielding, and execution of the electrometric amplifier. A specific method for the calculation of spectral ion characteristics and the mode of automatic calibration were proposed and a procedure of automatic measurement in the absence of attendants was set up. The measuring system is designed for studying and long-term monitoring of the concentration of light negative ions in dependence on climatic conditions and on the mobility of ions occurring in the cave.

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Pre-earthquake signals: Underlying physical processes

Cited by 244 publications

References 138 publications

Origin of Earthquake Light Associated with Earthquakes in Christchurch, New Zealand, 2010-2011

Origin of Earthquake Light Associated with Earthquakes in Christchurch, New Zealand, 2010-2011

Geosphere coupling and hydrothermal anomalies before the 2009 <i>M</i><sub>w</sub> 6.3 L'Aquila earthquake in Italy

Measuring Light Air Ions in a Speleotherapeutic Cave

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Pre-earthquake signals: Underlying physical processes

Cited by 244 publications

References 138 publications

Origin of Earthquake Light Associated with Earthquakes in Christchurch, New Zealand, 2010-2011

Origin of Earthquake Light Associated with Earthquakes in Christchurch, New Zealand, 2010-2011

Geosphere coupling and hydrothermal anomalies before the 2009 &lt;i&gt;M&lt;/i&gt;&lt;sub&gt;w&lt;/sub&gt; 6.3 L'Aquila earthquake in Italy

Measuring Light Air Ions in a Speleotherapeutic Cave

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Product

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Geosphere coupling and hydrothermal anomalies before the 2009 <i>M</i><sub>w</sub> 6.3 L'Aquila earthquake in Italy