A bipolar electric anomaly, with precursory features for the great earthquakes, obtained in laboratory condition by the electrode potential study Valentin Constantin FURNIC Ă Romanian Academy, Institute of Geodynamics, 19-21 Jean-Louis Calderon St, Bucharest – 37, Romania, R - 020032, tel:0040213172126, fax:0040213172120, e-mail: furnica@geodin.ro Supposing that volumes of crust, on both sides of a seismic fault, take over the tectonic stress in a different manner, the electromagnetic fields of thermal nature emitted in the ultralow frequency domain (the Kirchhoff’s law*) will be polarized in different modes and could influence the functioning of a double galvanic cell situated at distance . For its design, considering the rational parameters law of the geometrical crystallography domain, and taking into account that the three cylindrical electrodes, spaced at several centimeters on the same direction, must be made from the same metal (brass) and must have identical masses, we consider that the electric potential differences could be obtained by influencing the free electron dissipation in the electrolytic solution, a square cross section being selected for the central reference electrode (null, N). Two digital HP E2378A multimeters (mV/dc, input impedance >1000 M Ω ) close the external electric circuits between left (L) and null (N) cylinders, respectively between right (R) and null (N) cylinders, immersed in 7.5 litres of sodic chloride solution. The SLD_1 transducer system (Salt – Levogyrate – Dextrogyrate - no.1) is situated on the first floor of a building, in the central zone of Bucharest, with high level of cultural electric noise, 120 km away from Vrancea epicentral area (Figure 1). Figure 1 Cylinders of electrodes: L (Left; G = 84,00 mm; Φ = 13,00 mm), N ( Null; G = 24,22 mm; Φ = 24,22 mm) and R (Right; G = 43,58 mm; Φ = 18,04 mm) where: G – generatrix; Ф – diameter 1
The internal energies of the L, R, and N cylinders, with identical masses but of different proportions, get at thermodynamic equilibrium the W L , W R and R W N values. Together in a common electrolyte solution, in stationary conditions, the three electrodes formed this way, will reach the V L , V R R and V N levels of self-potentials. Because, by construction W L >W N >W R , the electric current in the R external circuits, constitued of thin wires and digital voltmeters, will flow from the L electrode to the N electrode and from the N electrode to the R electrode. Keeping like common reference the electric potential of the N electrode, an invers connection at the measuring device for the N ↔ R pair will result, which leads to an opposite sign for the ∆ V readings (mV). W L > W N ⇒ V L – V N W N > W R ⇒ V N – V R R Δ V L = V L – V N - Δ V R = V N – V R ________________ ∆ V L + (- Δ V R ) = V R = V L – V R ⇒ DIF = Δ V L - Δ V R L – V N + V N – V R = V L –V R R R R The “DIF” signal (DIF = V L - V R ) seems to be determined only by the R potentials of L and R electrodes, but V N reference potential controls the values of ∆ V L and ∆ V R R potential differences. At about 90 days after starting moment of measurements, between 15 February and 15 July 2001, both signals, representing variations of the electrode potential differences, were affected by a bipolar anomaly (Figure 2). This effect, in the DIF signal (Figure 3) take a bay-like anomaly aspect, but more extended (December, 2000 – August, 2001). In this time interval, the seismic activity of Vrancea was represented by three seismic events greater than 4.0R, in a good connection with some morphological details of the complex electric signal (Figure 4). Figure 2 2
Figure 3 Figure 4 3
It has been found an evident correlation between the SLD_1 electric anomaly and maximum of phases due to movement of Moon around the Earth (lunar and solar eclipses) and of Earth’s movement around the Sun (vernal equinox - VE). The beginning of the warm season, when the daylight become longer, is marked by the peak of the anomaly’s positive pole, in the spring equinox date (March, 21, 2001). Also, the “tail” of the anomaly seems to be imposed by the effect of June-July, 2001 lunar and solar eclipses, when the most important earthquake of year has occurred (8.4M, Peru, 23.06.2001), Figure 5. Figure 5 4
Three months (March, April and May, 2001) of the anomaly total duration lack in seisms greater than 7.0M (Figure 2). Making evident this feature for the 1973 – 2008 time domain, was found that the 1990 – 2000 interval was not characterized by quiet periods, resulting that the possible cause could be of electric nature. The 7.2R great earthquake produced in Vrancea on 4 March 1977 followed after such kind of seismic gap (Figure 6). Figure 6 5
Conclusions 1. The SLD_1 long period electric anomaly is the most interesting aspect of “the electrode effect of the global tectonic activity” (Furnica, 2002) taking into account the results over eight years (November 2000 – August 2008, Figure 7) of uninterrupted recordings using the SLD_1 transducer, and we consider it being specific for systems of three collinear electrodes. 2. If this kind of bipolar electric anomaly is not typical for electrodes after some months of continuously functioning like a galvanic cell, we must consider it a geodynamic indicator with predictive value on short, medium and long term, being included in the category of long period seismoelectric signals related to the large and very large earthquakes. Figure 7 6
_______________ * Observing Kirchhoff’s law which settles that “each substance absorbs the radiations which it can emit in the same conditions of pressure and temperature” (Oncescu et al., 1971), and considering Boltzmann’s relationship (Landsberg, 1958): ∞ ∫ ε ν ν = σ 4 d T , T 0 where: - T - absolute temperature; - σ - a constant; E ( ) - Kirchhoff’s law; ν ε = = ν - , T f , T ν , T A ν , T - E ν,Τ - the emission power of the body; - A ν,Τ - the absorption power of the body. ______________ References: Furnica C.,V., 2002. Electrode effects of the global tectonic activity. Paper presented at the international symposium “25 years of research in Earth Physics”, Bucharest, 27 September 2002. Landsberg, G., S., 1958. Optica. Editura tehnic ă , Bucure ş ti, 662p. Oncescu, M., Petrescu-Prahova, M., Petrescu-Prahova, I. ş i Popescu, Tr., 1971. Fizica. Editura didactic ă ş i pedagogic ă , Bucure ş ti. *** (2000 - 2004): Anuarul astronomic. Editura Academiei. *** Romanian Earthquake Catalogue ROMPLUS, Catalogue under continuous update, first published as: Oncescu, M.C., Mârza, V.I., Rizescu, M., Popa, M., 1999, The Romanian Earthquake Catalogue between 984-1997, in Vrancea Earthquakes: Tectonics, Hazard and Risk Mitigation, F. Wenzel, D. Lungu (eds.) & O. Novak (co-ed), pp. 43-47, Kluwer Academic Publishers, Dordrecht, Netherlands *** http://wwwneic,cr.usgs.gov/neis/epic/epic_global.html – Earthquake search: global search 7
Recommend
More recommend
