Earth-prints repository, logo   DSpace

About DSpace Software
|earth-prints home page | roma library | bologna library | catania library | milano library | napoli library | palermo library
Please use this identifier to cite or link to this item:

Authors: Palo, M.*
Cusano, P.*
Title: Wavefield decomposition and phase space dynamics of the seismic noise at Volcan de Colima, Mexico: evidence of a two-state source process
Title of journal: Nonlinear Processes in Geophysics
Series/Report no.: /20 (2013)
Publisher: Copernicus Publications
Issue Date: 18-Jan-2013
DOI: 10.5194/npg-20-71-2013
Keywords: Time series analysis
Colima volcano
Phase space
Independent Component Analysis
volcanic tremor
microseismic noise
Abstract: We analyse the seismic noise recorded at the Colima Volcano (Mexico) in the period December 2005–May 2006 by four broadband three-component seismic stations. Specifically, we characterize the spectral content of the signal and follow its time evolution along all the data set. Moreover, we infer the properties of the attractor in the phase space by false nearest neighbours analysis and Grassberger–Procaccia algorithm, and adopt a time-domain decomposition method (independent component analysis) to find the basic constituents (independent components) of the system. Constraints on the seismic wavefield are inferred by the polarization analysis. We find two states of the background seismicity visible in different time-intervals that are Phase A and Phase B. Phase A has a spectrum with two peaks at 0.15 Hz and 0.3 Hz, with the latter dominating, an attractor of correlation dimension close to 3, three quasi-monochromatic independent components, and a relevant fraction of craterpointing polarization solutions in the near-field. In Phase B, the spectrum is preserved but with the highest peak at 0.15 Hz, the attractor has a correlation dimension close to 2, two independent components are extracted, and the polarization solutions are dominated by Rayleigh waves incoming from the southwest direction. We depict two sources acting on the background seismicity that are the microseismic noise loading on the Pacific coastline and a low-energy volcanic tremor. A change in the amplitude of the macroseismic noise can induce the switching from a state of the system to the other.
Appears in Collections:04.06.08. Volcano seismology
Papers Published / Papers in press

Files in This Item:

File Description SizeFormatVisibility
Palo&Cusano2013NPG.pdfArticle34.93 MBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Share this record




Stumble it!



Valid XHTML 1.0! ICT Support, development & maintenance are provided by CINECA. Powered on DSpace Software. CINECA