scholarly journals Surface wave tomography of the western United States from ambient seismic noise: Rayleigh wave group velocity maps

2007 ◽  
Vol 8 (8) ◽  
pp. n/a-n/a ◽  
Author(s):  
M. P. Moschetti ◽  
M. H. Ritzwoller ◽  
N. M. Shapiro
Keyword(s):  
United States ◽  
Surface Wave ◽  
Rayleigh Wave ◽  
Group Velocity ◽  
Seismic Noise ◽  
Western United States ◽  
Ambient Seismic Noise ◽  
Wave Group ◽  
Surface Wave Tomography ◽  
Wave Tomography

scholarly journals Surface wave tomography of China from ambient seismic noise correlation

2008 ◽  
Vol 9 (5) ◽  
pp. n/a-n/a ◽  
Author(s):  
Sihua Zheng ◽  
Xinlei Sun ◽  
Xiaodong Song ◽  
Yingjie Yang ◽  
Michael H. Ritzwoller
Keyword(s):  
Surface Wave ◽  
Seismic Noise ◽  
Ambient Seismic Noise ◽  
Noise Correlation ◽  
Surface Wave Tomography ◽  
Wave Tomography

scholarly journals Rayleigh wave group velocity distributions for East Asia using ambient seismic noise

2014 ◽  
Vol 41 (22) ◽  
pp. 8045-8052 ◽  
Author(s):  
Michael Witek ◽  
Suzan van der Lee ◽  
Tae-Seob Kang
Keyword(s):  
Rayleigh Wave ◽  
East Asia ◽  
Group Velocity ◽  
Seismic Noise ◽  
Ambient Seismic Noise ◽  
Wave Group

scholarly journals Source depopulation potential and surface-wave tomography using a crosscorrelation method in a scattering medium

Geophysics ◽  
2011 ◽  
Vol 76 (2) ◽  
pp. SA51-SA61 ◽  
Author(s):  
Pierre Gouédard ◽  
Philippe Roux ◽  
Michel Campillo ◽  
Arie Verdel ◽  
Huajian Yao ◽  
...  
Keyword(s):  
Surface Wave ◽  
Rayleigh Wave ◽  
Group Velocity ◽  
Mean Free Path ◽  
Dispersion Curves ◽  
Velocity Analysis ◽  
Surface Wave Tomography ◽  
Shallow Subsurface ◽  
Active Source ◽  
Wave Tomography

We use seismic prospecting data on a 40 × 40 regular grid of sources and receivers deployed on a 1 km × 1 km area to assess the feasibility and advantages of velocity analysis of the shallow subsurface by means of surface-wave tomography with Green’s functions estimated from crosscorrelation. In a first application we measure Rayleigh-wave dispersion curves in a 1D equivalent medium. The assumption that the medium is laterally homogeneous allows using a simple projection scheme and averaging of crosscorrelation functions over the whole network. Because averaging suppresses noise, this method yields better signal-to-noise ratio than traditional active-source approaches, and the improvement can be estimated a priori from acquisition parameters. We find that high-quality dispersion curves can be obtained even when we reduce the number of active sources used as input for the correlations. Such source depopulation can achieve significant reduction in the cost of active source acquisition. In a second application we compare Rayleigh-wave group velocity tomography from raw and reconstructed data. We can demonstrate that the crosscorrelation approach yields group velocity maps that are similar to active source maps. Scattering has an importance here as it may enhance the crosscorrelation performance. We quantify the scattering properties of the medium using mean free path measurements from coherent and incoherent parts of the signal. We conclude that for first-order velocity analysis of the shallow subsurface, the use of crosscorrelation offers a cost-effective alternative to methods that rely exclusively on active sources.

scholarly journals Crust and upper mantle structures of the Makran subduction zone in south-east Iran by seismic ambient noise tomography

2014 ◽  
Vol 6 (1) ◽  
pp. 1-34 ◽  
Author(s):  
M. Abdetedal ◽  
Z. H. Shomali ◽  
M. R. Gheitanchi
Keyword(s):  
Surface Wave ◽  
Rayleigh Wave ◽  
Group Velocity ◽  
Ambient Noise ◽  
Surface Wave Tomography ◽  
Seismic Ambient Noise ◽  
Velocity Anomaly ◽  
Empirical Green’S Functions ◽  
Wave Tomography ◽  
Cross Correlations

Abstract. We applied seismic ambient noise surface wave tomography to estimate Rayleigh wave empirical Green's functions from cross-correlations to study crust and uppermost mantle structure beneath the Makran region in south-east Iran. We analysed 12 months of continuous data from January 2009 through January 2010 recorded at broadband seismic stations. We obtained group velocity of the fundamental mode Rayleigh-wave dispersion curves from empirical Green's functions between 10 and 50 s periods by multiple-filter analysis and inverted for Rayleigh wave group velocity maps. The final results demonstrate significant agreement with known geological and tectonic features. Our tomography maps display low-velocity anomaly with south-western north-eastern trend, comparable with volcanic arc settings of the Makran region, which may be attributable to the geometry of Arabian Plate subducting overriding lithosphere of the Lut block. At short periods (<20 s) there is a pattern of low to high velocity anomaly in northern Makran beneath the Sistan Suture Zone. These results are evidence that surface wave tomography based on cross correlations of long time-series of ambient noise yields higher resolution group speed maps in those area with low level of seismicity or those region with few documented large or moderate earthquake, compare to surface wave tomography based on traditional earthquake-based measurements.

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