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On amplitude information carried by the ambient seismic field

German A. Prieto, Marine A. Denolle, Jesse F. Lawrence, & Gregory C. Beroza

Under Review 2010, SCEC Contribution #1461

The use of the ambient seismic field (ASF) to extract Earth’s response has received significant attention in the last few years. Multiple studies demonstrate the utility of the ASF for resolving high-resolution velocity models in various locations. In this paper we discuss the amplitude information carried by the ASF. Amplitude information includes both amplification effects due to elastic structure, such as low velocity sedimentary basins, and attenuation effects in buildings or in the crust and upper mantle. As has been suggested by other authors, amplitude measurements may be biased due to a nonuniform ambient field; however, we find very similar results for different time intervals in both cases (amplification and attenuation) suggesting that this bias may not be as large as feared. We suggest that amplitude measurements may also be used for seismic monitoring, and may be particularly valuable due to the enhanced sensitivity of attenuation to fluids and/or temperature fluctuations.

Prieto, G. A., Denolle, M. A., Lawrence, J. F., & Beroza, G. C. (2010). On amplitude information carried by the ambient seismic field. Comptes rendus geoscience: Imaging and Monitoring with Seismic Noise, (under review).