We analyze time series of Strombolian volcanic tremor, focusing our attention on the frequency band [0.1-0.5] Hz (very long period (VLP) tremor). Although this frequency band is largely affected by noise, we evidence two significant components by using Independent Component Analysis with the frequencies, respectively, of ∼0.2 and ∼0.4 Hz. We show that these components display wavefield features similar to those of the high frequency Strombolian signals (>0.5Hz). In fact, they are radially polarised and located within the crater area. This characterization is lost when an enhancement of energy appears. In this case, the presence of microseismic noise becomes relevant. Investigating the entire large data set available, we determine how microseismic noise influences the signals. We ascribe the microseismic noise source to Scirocco wind. Moreover, our analysis allows one to evidence that the Strombolian conduit vibrates like the asymmetric cavity associated with musical instruments generating self-sustained tones.

Statistical analysis of Stromboli VLP tremor in the band [0.1-0.5] Hz: some consequences for vibrating structure / DE LAURO, E; DE MARTINO, S; Falanga, M; Palo, M. - In: NONLINEAR PROCESSES IN GEOPHYSICS. - ISSN 1023-5809. - 13:(2006), pp. 393-400. [10.5194/npg-13-393-2006]

Statistical analysis of Stromboli VLP tremor in the band [0.1-0.5] Hz: some consequences for vibrating structure

PALO M
2006

Abstract

We analyze time series of Strombolian volcanic tremor, focusing our attention on the frequency band [0.1-0.5] Hz (very long period (VLP) tremor). Although this frequency band is largely affected by noise, we evidence two significant components by using Independent Component Analysis with the frequencies, respectively, of ∼0.2 and ∼0.4 Hz. We show that these components display wavefield features similar to those of the high frequency Strombolian signals (>0.5Hz). In fact, they are radially polarised and located within the crater area. This characterization is lost when an enhancement of energy appears. In this case, the presence of microseismic noise becomes relevant. Investigating the entire large data set available, we determine how microseismic noise influences the signals. We ascribe the microseismic noise source to Scirocco wind. Moreover, our analysis allows one to evidence that the Strombolian conduit vibrates like the asymmetric cavity associated with musical instruments generating self-sustained tones.
2006
Statistical analysis of Stromboli VLP tremor in the band [0.1-0.5] Hz: some consequences for vibrating structure / DE LAURO, E; DE MARTINO, S; Falanga, M; Palo, M. - In: NONLINEAR PROCESSES IN GEOPHYSICS. - ISSN 1023-5809. - 13:(2006), pp. 393-400. [10.5194/npg-13-393-2006]
File in questo prodotto:
File Dimensione Formato  
npg-13-393-2006.pdf

non disponibili

Dimensione 649.71 kB
Formato Adobe PDF
649.71 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11588/873139
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 19
  • ???jsp.display-item.citation.isi??? 18
social impact