Pre-earthquake signals – Part I: Deviatoric stresses turn rocks into a source of electric currents

Freund, Friedemann

doi:10.5194/nhess-7-535-2007

Cited by 67 publications

(61 citation statements)

References 57 publications

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“…Freund and Hermance [7][8][9], showed different sources of electrical charges generated by rocks. The first aim of this research is to find out the possible connections between the sunspot variations and their influence on the earthquakes.…”

Section: Introductionmentioning

confidence: 99%

Influences of Solar Cycles on Earthquakes

Tavares¹,

Azevedo²

2011

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This paper inspects possible influence of solar cycles on earthquakes through of statistical analyses. We also discussed the mechanism that would drive the occurrence of increasing of earthquakes during solar maxima. The study was based on worldwide earthquakes events during approximately four hundred years (1600-2010).The increase of earthquakes events followed the Maxima of Solar cycle, and also depends on the tectonic plate location. From 1600 until 1645 events increased during the Maxima in some of the tectonic plates as Pacific, Arabian and South America. The earthquakes analyzed during two grand solar minima, the Maunder (1645-1720) and the Dalton (1790-1820) showed a decrease in the number of earthquakes and the solar activity. It was observed during these minima a significant number of events at specific geological features. After the last minima (Dalton) the earthquakes pattern increased with solar maxima. The calculations showed that events increasing during solar maxima most in the Pacific, South America or Arabian until 1900. Since there were few records during these three centuries we needed additional analysis on modern data. We took the last four solar cycles events (1950-2010) and made similar calculations. The results agreed with the former calculations. It might be that the mechanism for the Sun-Earth connection relies on the solar wind speed. In both records (1600-1900) and (1950-2010) the results showed a significant increase in earthquakes events in some of the tectonic plates linked to solar maxima. The Solar wind energy striking the Earth's magnetosphere affects the entire environment because the pressure on the region increases and the magnetosphere shrinks sometimes four Earth's radii. This sudden compression causes earthquakes in specific plates. During the times of solar minima the pressure from the solar wind on the earth decreases, then the magnetosphere expands and earthquakes happen in a different pattern according to the geological feature on earth's surface less frequently. Solar driven events include coronal mass ejections (CME) and coronal holes, which are at a maximum during the descending phase of solar activity. The tectonic are important because there is heterogeneity in the crust and the tectonic stress depends on each region. The geo-effectiveness of solar wind from a coronal hole only depends on the position of the hole relative to the Earth and for the CMEs an additional factor is their velocity. The influence of these solar events could be detected from electromagnetic variations on the ground prior the earthquakes. The goal in this research was to show the solar events influenced the earthquakes and seismologic events following some special display and also how the Sun's activity played to make earthquakes increase. This paper discussed details of this mechanism, calculations and associated factors.

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Section: Introductionmentioning

confidence: 99%

Influences of Solar Cycles on Earthquakes

Tavares¹,

Azevedo²

2011

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“…These three simultaneous EM phenomena were compared with data collected over a 1-2-year period at the site. The data was also compared against accounts of air ionization reported to be associated with radon emission from the ground (Ouzounov, 2007), and a series of laboratory rock stressing experiments (Freund, 2006(Freund, , 2007a to determine if field data was consistent either of these accounts. We could not find a data set with preearthquake radon measurements taken near the Alum Rock epicenter to compare against our field data.…”

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confidence: 99%

“…It further examines these signatures in the context of a recent theory of pre-earthquake processes. One theory (Freund, 2006(Freund, , 2007a involves the generation of p-hole charge carriers during asymmetric rock stress, and the resulting underground currents and ULF magnetic fields. The theory also addresses the migration of the charge carriers to the surface where they change the local surface air conductivity and may create apparent IR heating signatures as observed by satellite instruments during the earthquake preparation process.…”

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confidence: 99%

Investigation of ULF magnetic pulsations, air conductivity changes, and infra red signatures associated with the 30 October Alum Rock M5.4 earthquake

Bleier

Dunson

Maniscalco

et al. 2009

Nat. Hazards Earth Syst. Sci.

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Abstract. Several electromagnetic signal types were observed prior to and immediately after 30 October 2007 (Local Time) M5.4 earthquake at Alum Rock, Ca with an epicenter ∼15 km NE of San Jose Ca. The area where this event occurred had been monitored since November 2005 by a QuakeFinder magnetometer site, unit 609, 2 km from the epicenter. This instrument is one of 53 stations of the QuakeFinder (QF) California Magnetometer NetworkCalMagNet. This station included an ultra low frequency (ULF) 3-axis induction magnetometer, a simple air conductivity sensor to measure relative airborne ion concentrations, and a geophone to identify the arrival of the P-wave from an earthquake. Similar in frequency content to the increased ULF activity reported two weeks prior to the Loma Prieta M7.0 quake in 1989 (Fraser-Smith, 1990, 1991, the QF station detected activity in the 0.01-12 Hz bands, but it consisted of an increasing number of short duration (1 to 30 s duration) pulsations. The pulsations peaked around 13 days prior to the event. The amplitudes of the pulses were strong, (3-20 nT), compared to the average ambient noise at the site, (10-250 pT), which included a component arising from the Bay Area Rapid Transit (BART) operations. The QF station also detected different pulse shapes, e.g. negative or positive only polarity, with some pulses including a combination of positive and negative. Typical pulse counts over the previous year ranged from 0-15 per day, while the count rose to 176 (east-west channel) on 17 October, 13 days prior to the quake. The air conductivity sensor saturated for over 14 h during the night and morning prior to the quake, which occurred at 20:29 LT. Anomalous IR signatures were also Correspondence to: T. Bleier (tbleier@quakefinder.com) observed in the general area, within 50 km of the epicenter, during the 2 weeks prior to the quake. These three simultaneous EM phenomena were compared with data collected over a 1-2-year period at the site. The data was also compared against accounts of air ionization reported to be associated with radon emission from the ground (Ouzounov, 2007), and a series of laboratory rock stressing experiments (Freund, 2006(Freund, , 2007a to determine if field data was consistent either of these accounts. We could not find a data set with preearthquake radon measurements taken near the Alum Rock epicenter to compare against our field data. However, based on the Alum Rock data set example and another data set at Parkfield, the field tests are at least consistent with the lab experiments showing currents, magnetic field disturbances, air conductivity changes, and IR signatures. This is encouraging, but more instrumented earthquake examples are needed to prove a repeating pattern for these types of pre-earthquake EM signatures.

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“…Those models include positive hole charge carriers (Freund 2007;Freund et al 2009;Freund and Pilorz 2012), the piezoelectric effect of quartz (Nitsan 1977), the electrokinetic effect due to water filtration (Ishido and Mizutani 1981), pressure stimulated currents (Varotsos and Alexopoulos 1984b) arising from the (re)orientation of electric dipoles due to lattice defects (Londos et al 1996) formed mainly in the ionic constituents of rocks, and so forth. Of the many kinds of earthquake precursors, earthquake forecasting using geoelectromagnetic fields is claimed to have some promising potential (Varotsos and Alexopoulos 1984a, b;Kawase et al 1993;Varotsos et al 1993Varotsos et al , 2006aVarotsos et al , b, 2008Varotsos et al , 2009Varotsos et al , 2011aVarotsos et al , 2013Uyeda et al 2000Uyeda et al , 2002Eftaxias et al 2004Eftaxias et al , 2007Eftaxias et al , 2013Telesca et al 2004Telesca et al , 2005Telesca et al , 2008Telesca et al , 2009Orihara et al 2009Orihara et al , 2012Eftaxias 2010;Ramirez-Rojas et al 2013;Chen and Chen 2016).…”

Section: Introductionmentioning

confidence: 99%

Using geoelectric field skewness and kurtosis to forecast the 2016/2/6, ML 6.6 Meinong, Taiwan Earthquake

Chen¹,

Chen²,

Ouillon³

et al. 2017

Terr. Atmos. Ocean. Sci.

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The earthquake-alarm model developed by Chen and Chen (Nat. Hazards 2016) is investigated to validate its forecasting performance for the 2016/2/6, M L 6.6 Meinong, Taiwan earthquake. This alarm model is based on geoelectric field skewness and kurtosis anomalies. The model parameters, such as the detection range and predicted time window, allow us to estimate the empirical relationships between geoelectric anomalies and large earthquakes. As a result, the skewness and kurtosis anomalies are shown to appear before the Meinong earthquake on the four neighboring stations (LIOQ, WANL, KAOH, and CHCH). According to the model analysis a time lag exists between anomaly clusters and earthquakes, depending on local geological features, as well as the durations over which anomalies are continuously observed, which might also display time dependence. In conclusion, this alarm model is able to correlate earthquakes and geoelectrical anomalies, with promising usefulness in forecasting large earthquakes.

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Pre-earthquake signals – Part I: Deviatoric stresses turn rocks into a source of electric currents

Cited by 67 publications

References 57 publications

Influences of Solar Cycles on Earthquakes

Influences of Solar Cycles on Earthquakes

Investigation of ULF magnetic pulsations, air conductivity changes, and infra red signatures associated with the 30 October Alum Rock M5.4 earthquake

Using geoelectric field skewness and kurtosis to forecast the 2016/2/6, ML 6.6 Meinong, Taiwan Earthquake

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