Open AccessObservations of short period seismic scattered waves by small seismic arrays
Author(s) -
Edoardo Del Pezzo,
Mario La Rocca,
Rosalba Maresca,
M. Simini
Publication year - 1997
Publication title -
annals of geophysics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.394
H-Index - 60
eISSN - 2037-416X
pISSN - 1593-5213
DOI - 10.4401/ag-3852
Subject(s) - coda , seismogram , seismology , geology , rayleigh scattering , scattering , volcano , polarization (electrochemistry) , azimuth , rayleigh wave , seismic wave , geophysics , surface wave , physics , optics , chemistry
The most recent observations of well correlated seismic phases in the high frequency coda of local earthquakes recorded throughout the world are reported. In particular the main results, obtained on two active volcanoes, Teide and Deception, using small array are described. The ZLC (Zero Lag Cross-correlation) method and polarization analysis have been applied to the data in order to distinguish the main phases in the recorded seismograms and their azimuths and apparent velocities. The results obtained at the Teide volcano demonstrate that the uncorrelated part of the seismograms may be produced by multiple scattering from randomly distributed heterogeneity, while the well correlated part, showing SH type polarization or the possible presence of Rayleigh surface waves, may be generated by single scattering by strong scatterers. At the Deception Volcano strong scattering, strongly focused in a precise direction, is deduced from the data. In that case, all the coda radiation is composed of surface waves