Estimating the Rayleigh-wave impulse response between seismic stations with the cross terms of the Green tensor

• Published in: Geophysical research letters Vol. 38; no. 16
• Main Authors: van Wijk, Kasper, Mikesell, T. Dylan, Schulte-Pelkum, Vera, Stachnik, Josh
• Format: Journal Article
• Language: English
• Published: Washington, DC Blackwell Publishing Ltd 01.08.2011; American Geophysical Union; John Wiley & Sons, Inc
• Subjects: ambient noise tomography; Earth sciences; Earth, ocean, space; Estimates; Exact sciences and technology; Impulse response; Mathematical analysis; Noise; Rayleigh waves; Seismic engineering; Seismic phenomena; Seismology; Stations; Surface waves; Tensors; cross-correlation; Rayleigh waves; windows; subsurface; tensor; Velocity dispersion; phase velocity; batholiths; Earth; seismic stations; surface waves; Pulse response; tomography; signal-to-noise ratio; noise; vertical component
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/2011GL047442

The development of ambient noise tomography has provided a powerful tool to investigate the Earth's subsurface with increased resolution. Most commonly, surface‐wave tomography is performed on inter‐station estimates of the vertical component of Rayleigh waves, stemming from crosscorrelations of ocean‐generated noise. Here, we estimate the cross terms of the Rayleigh‐wave Green tensor, and show this is less sensitive to signal not in‐line with the seismic stations. We illustrate this result with the Batholiths temporary seismic deployment, showing estimates of the Rayleigh wave with a higher signal‐to‐noise ratio and a consequently better phase‐velocity dispersion curve. This approach provides an opportunity for reliable ambient noise crosscorrelations over shorter time windows and more closely spaced stations in the future. Key Points Ambient noise correlations can suffer from artefacts Our new method reduces these artefacts significantly We illustrate our ideas in passive data from the Batholiths experiment