On measuring surface wave phase velocity from station-station cross-correlation of ambient signal
Research output: Contribution to journal › Journal article › Research › peer-review
We apply two different algorithms to measure surface wave phase velocity, as a function of frequency, from seismic ambient noise recorded at pairs of stations from a large European network. The two methods are based on consistent theoretical formulations, but differ in the implementation: one method involves the time-domain cross-correlation of signal recorded at different stations; the other is based on frequency-domain cross-correlation, and requires finding the zero-crossings of the real part of the cross-correlation spectrum. Furthermore, the time-domain method, as implemented here and in the literature, practically involves the important approximation that interstation distance be large compared to seismic wavelength. In both cases, cross-correlations are ensemble-averaged over a relatively long period of time (1 yr). We verify that the two algorithms give consistent results, and infer that phase velocity can be successfully measured through ensemble-averaging of seismic ambient noise, further validating earlier studies that had followed either approach. The description of our experiment and its results is accompanied by a detailed though simplifed derivation of ambient-noise theory, writing out explicitly the relationships between the surface wave Green's function, ambient-noise cross-correlation and phase and group velocities
Original language | English |
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Journal | Geophysical Journal International |
Volume | 192 |
Issue number | 1 |
Pages (from-to) | 346-358 |
Number of pages | 13 |
ISSN | 0956-540X |
DOIs | |
Publication status | Published - 26 Mar 2013 |
Externally published | Yes |
- Crustal structure, Interferometry, Seismic tomography, Theoretical seismology, Time-series analysis
Research areas
ID: 188757187