Ambient noise surface wave tomography across Europe: Rayleigh wave group and phase speed measurements.

摘要

We present ambient noise tomography results of Rayleigh wave group and phase velocities obtained from empirical Green's functions produced by cross-correlating long ambient noise sequences between available station pairs across Europe. Cross-correlations are stacked over the entire time-series and are used to obtain group and phase velocity dispersion curves from 5-100 sec period. Measurement uncertainties based on seasonal variations are estimated from temporal subsets of the data. We construct tomographic maps from 10-60 sec period, which are interpreted in the context of the characteristics of the crust and upper mantle throughout Europe. We improve upon the initial results obtained in Europe by Yang et al. (2007) by including longer time series, a larger dataset, and phase as well as group speed measurements. Our dataset results in geographically expanded regions of high path density and resolution, especially across France, the Iberian Peninsula, the Mediterranean, Eastern Europe, and Turkey.