wp-1-1: methodological improvements for 3d reconstructions contributors: pierre gouédard, philippe...
Post on 21-Dec-2015
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WP-1-1: Methodological improvements for 3D reconstructions
Contributors: Pierre Gouédard, Philippe Roux, Seiji Tsuno, Marc Wathelet
What has been done/initiated ?
ESG2006 noise blind test Estimation of dispersion curves is OK Interpretation of mode branches and inversion of Vs profiles are critical issues
Comparison between SPAC/FK et noise correlation techniques => performance and limits of these “competing” approaches => what kind of “correlation technique and array layout” to use for imaging subsurface shear-wave velocity
MASW measurements for getting information on the shallow layers (Vs, Qs) high frequency technique (10-80 Hz) complementary to noise array technique
Comparison between SPAC/FK and noise correlation
resolution limit D ~ max
aliasing limit 2d ~ min
resolution limit D ~ max
aliasing limit 2d ~ min
reliable
Mapping resolution and aliasing limits into f-c domain
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Isotropic noise directional noise
HRFK
CORR
Comparison SPAC/FK and noise correlation
• Similar performance at low frequency (controlled by array aperture)
• Better performance of noise correlation at high frequency (although a similar array layout, effective spatial aliasing is different)
• Noise correlation allows estimating both Rayleigh and Love waves dispersion curves (also for SPAC3C but not so straightforwardly for FK techniques)
• Future studies on performance of correlation techniques application of correlation to 2D structures (array aperture frequency range 2D site)