Fractal characteristics of the natural ULF emissions in relation to geomagnetic activity

Author

Smirnova, N.A. ; Yakovitskaya, I.V. ; Hayakawa, Russia M. ; Itoh, T.

Author_Institution

Inst. of Phys., St. Petersburg State Univ., Russia

fYear

2005

fDate

21-24 June 2005

Firstpage

243

Lastpage

247

Abstract

Fractal analysis of the ULF emissions registered at low-latitude observatory Guam (Φ_m=9°N, Λ_m=225°) has been performed. Dynamics of scaling characteristics (spectral exponents β and fractal dimensions D0) has been analyzed depending on the level of geomagnetic activity and in relation to the nearby earthquake of August 8, 1993. It is found that the spectrum of ULF emissions exhibits power law behavior S(f)∞f-β which is typical for fractal (self-affine) time series. It is also revealed that spectral exponent β varies in the range β=0.7-2.5 in correlation with Kp-index of geomagnetic activity, and manifests a downward tendency when approaching the earthquake date. The results obtained are discussed on the basis of the SOC (self-organized criticality) approach to study the ULF emission source dynamics.

Keywords

earthquakes; fractals; geomagnetic variations; seismic waves; self-organised criticality; spectral analysis; time series; earthquake; fractal characteristics; geomagnetic activity; low-latitude Guam observatory; natural ULF emission; power law behavior; scaling characteristics dynamic; self-organized criticality; spectral exponent; time series; Earthquakes; Fractals; Geomagnetism; Magnetic analysis; Magnetic materials; Magnetic separation; Magnetosphere; Observatories; Physics; Signal analysis;

fLanguage

English

Publisher

ieee

Conference_Titel

Electromagnetic Compatibility and Electromagnetic Ecology, 2005. IEEE 6th International Symposium on

Print_ISBN

0-7803-9374-0

Type

conf

DOI

10.1109/EMCECO.2005.1513114

Filename

1513114