Dispersion of interface waves in sediments with power-law shear speed profiles. II. Experimental observations and seismo-acoustic inversions.

摘要: The propagation of seismic interface waves is investigated in soft marine sediments which the density constant, shear modulus small, and profile speed c(s) versus depth z power-law form (z) = c0z(v), c0 v are constants (0< < 1). Both phase V group U scale with frequency as f(v/(v -1)) they obey simple relation U= (1 - v) V. These relations derived a way using ray theory WKB method; companion paper [O. A. Godin D. M. F. Chapman, J. Acoust. Soc. Am. 110, 1890 (2001)] rigorously derives same result from solutions to equations motion. scaling shown exist experimental data sets wave speed. Approximate analytical formulas for dispersion (phase frequency) enable direct inversion parameters data. In cases there multi-mode data, water-sediment ratio can be determined well. applies vertically polarized (P-SV) modes well horizontally (SH) (that is, Love waves).