Articles | Volume 13, issue 1
Nat. Hazards Earth Syst. Sci., 13, 187–191, 2013
Nat. Hazards Earth Syst. Sci., 13, 187–191, 2013

Review article 29 Jan 2013

Review article | 29 Jan 2013

On the multi-fractal characteristics of the ULF geomagnetic field before the 1993 Guam earthquake

F. Masci F. Masci
  • Istituto Nazionale di Geofisica e Vulcanologia, L'Aquila, Italy

Abstract. Ida et al. (2005) document significant changes in the multi-fractal parameters of the ULF geomagnetic field H component starting about one month before the 1993 Guam earthquake. According to the authors, these multi-fractal signatures can be considered as precursory signals of the Guam earthquake. As a consequence, they conclude that the multi-fractal analysis may have an important role in the development of short-term earthquake prediction capabilities. Since this and other similar reports have motivated the idea that earthquake prediction based on electromagnetic precursory signals may one day become a routine technique, the presumed precursors need to be validated through independent datasets. In this review the seismogenic origin of the multi-fractal magnetic signatures documented by Ida et al. (2005) before the 8 August 1993 Guam earthquake is seriously put into question. By means of the geomagnetic ΣKp index, it is demonstrated that these multi-fractal parameter changes are normal signals induced by the variation of the global geomagnetic activity level.