Please use this identifier to cite or link to this item:
http://hdl.handle.net/2122/2818
Authors: | Bianco, F.* Del Pezzo, E.* Castellano, M.* Ibanez, J.* Di Luccio, F.* |
Title: | Separation of intrinsic and scattering seismic attenuation in the Southern Apennine zone, Italy | Journal: | Geophysical Journal International | Series/Report no.: | 150 | Publisher: | RAS | Issue Date: | 2002 | Keywords: | absorption scattering seismic coda |
Subject Classification: | 04. Solid Earth::04.06. Seismology::04.06.09. Waves and wave analysis | Abstract: | Scattered waves observed at the seismographs of the National Italy’s seismic network have been used to investigate the intrinsic dissipation and scattering properties of the lithosphere under the Southern Apennines, Italy. First, we investigate the coda-Q properties, then we apply theMLTWanalysis in the hypothesis of velocity and scattering coefficient constant with depth, and finally we interpret these results with the aid of numerical simulations in a medium with depth dependent velocity and scattering coefficient. Results obtained in the hypothesis of a uniform model show that a low scattering-Q−1 and a relatively higher intrinsic-Q−1 characterize the lithosphere of the Southern Apennines. Numerical simulations of the seismogram energy envelopes were performed hypothesizing a strongly scattering crust and trasparent upper mantle, both with reasonable intrinsic dissipation coefficients. In these symplifying assumptions the theoretical curves calculated for the homogeneous model fit to the synthetic envelopes with scattering attenuation coefficients always greater than the synthetic values. This results lead to the consideration that scattering-Q−1 obtained using MLTW analysis under the assumption of uniform medium are overestimated. The values of the scattering-Q−1 estimated for Apennines at low frequency (1–2 Hz) in the hypothesis of uniform medium are of the same order of those obtained in several areas around the world. The estimates obtained for frequencies ranging from 2 to 12 Hz are very low if compared with those obtained in the same hypothesis for other areas around the world. Coda Q−1 closely resembles intrinsic Q−1. |
Appears in Collections: | Article published / in press |
Files in This Item:
File | Description | Size | Format | Existing users please Login |
---|---|---|---|---|
GJI_1696.pdf | Main article | 540.34 kB | Adobe PDF |
Page view(s)
164
checked on Apr 24, 2024
Download(s)
21
checked on Apr 24, 2024