Magnetic transfer function entropy and the 2009 <i>M</i><sub>w</sub> = 6.3 L'Aquila earthquake (Central Italy)
-
Published:2012-07-23
Issue:4
Volume:19
Page:401-409
-
ISSN:1607-7946
-
Container-title:Nonlinear Processes in Geophysics
-
language:en
-
Short-container-title:Nonlin. Processes Geophys.
Author:
Cianchini G.,De Santis A.,Barraclough D. R.,Wu L. X.,Qin K.
Abstract
Abstract. With the aim of obtaining a deeper knowledge of the physical phenomena associated with the 2009 L'Aquila (Central Italy) seismic sequence, culminating with a Mw = 6.3 earthquake on 6 April 2009, and possibly of identifying some kind of earthquake-related magnetic or geoelectric anomaly, we analyse the geomagnetic field components measured at the magnetic observatory of L'Aquila and their variations in time. In particular, trends of magnetic transfer functions in the years 2006–2010 are inspected. They are calculated from the horizontal to vertical magnetic component ratio in the frequency domain, and are very sensitive to deep and lateral geoelectric characteristics of the measurement site. Entropy analysis, carried out from the transfer functions with the so called transfer function entropy, points out clear temporal burst regimes of a few distinct harmonics preceding the main shock of the seismic sequence. A possible explanation is that they could be related to deep fluid migrations and/or to variations in the micro-/meso-fracturing that affected significantly the conductivity (ordered/disordered) distribution in a large lithospheric volume under the seismogenic layer below L'Aquila area. This interpretation is also supported by the analysis of hypocentres depths before the main shock occurrence.
Publisher
Copernicus GmbH
Reference35 articles.
1. Armadillo, E., Bozzo, E., Cerv, V., De Santis, A., Di Mauro, D., Gambetta, M., Meloni, A., Pek, J., and Speranza, F.: Geomagnetic depth sounding in the Northern Appennines (Italy), Earth Planet. Space, 53, 385–396, 2001. 2. Banks, R.: Data processing and interpretation in geomagnetic deep sounding, Phys. Earth Planet Int., 7, 339–348, 1973. 3. Banks, R.: Geomagnetic deep sounding, in: Encyclopedia of Geomagnetism and Paleomagnetism, edited by: Gubbins, D. and Herrero-Bervera, E., 307–310, 2007. 4. Basili, R., Valensise, G., Vannoli, P., Burrato, P., Fracassi, U., Mariano, S., Tiberti, M. M., and Boschi, E.: The Database of Individual Seismogenic Sources (DISS), version 3: summarizing 20 years of research on Italy's earthquake geology, Tectonophysics, 453, 20–43, https://doi.org/10.1016/j.tecto.2007.04.014, 2008. 5. Bonafede, M., Ferrari, C., Maccaferri, F., and Stefánsson, R.: On the preparatory processes of the M6.6 earthquake of June 17th 2000, in Iceland, Geoph. Res. Lett., 34, L24305, https://doi.org/10.1029/2007GL031391, 2007.
Cited by
7 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献
|
|