NHESS Natural Hazards and Earth System Sciences NHESS Nat. Hazards Earth Syst. Sci. 1684-9981 Copernicus Publications Göttingen, Germany 10.5194/nhess-4-663-2004 Principal component analysis of geoelectrical signals measured in the seismically active area of Basilicata Region (southern Italy) Telesca L. 1 Colangelo G. 1 Hattori K. 2 Lapenna V. 1 Istituto di Metodologie per l’Analisi Ambientale, CNR, Tito (PZ), Italy Marine Biosystems Research Center, Chiba University, Japan 01 11 2004 4 5/6 663 667 Copyright: © 2004 L. Telesca et al. 2004 This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 2.5 Generic License. To view a copy of this licence, visit https://creativecommons.org/licenses/by-nc-sa/2.5/ This article is available from https://nhess.copernicus.org/articles/4/663/2004/nhess-4-663-2004.html The full text article is available as a PDF file from https://nhess.copernicus.org/articles/4/663/2004/nhess-4-663-2004.pdf

Geoelectrical fluctuations are the end product of several geophysical phenomena. In particular geoelectrical signals measured in seismically active areas can be attributed to stress and strain changes, associated with earthquakes. The complexity of this problem has suggested the development of advanced statistical methods to investigate the heterogeneous nature of these fluctuations. In this paper we analysed the time dynamics of short-term variability of geoelectrical field measured at Giuliano station, located in Basilicata Region, one of the most seismically active areas of southern Italy. We applied the principal component analysis (PCA). The analysis has shown earthquake precursory patterns in the daily variation of the principal components, revealing that the PCA approach is promising for monitoring seismic areas.