Shear properties of ocean sediments determined from numerical modelling of Scholte wave data
Abstract
Recently it has become apparent that shear properties of ocean sediments are most easily determined from measured propagation characteristics of seismic interface waves. We use a newly developed numeri ca l model of wave propagation in horizontally stratified viscoelastic media to reconstruct from Scholte-wave records the shear-speed and shearattenuation profiles in the upper sediment layers of a shallow-water test area. For an unconsolidated sand-silt bottom we find the shear speed to increase with depth from 85 mls at the sea floor to 300 ml s a t 60 m depth. On the other hand, the shear attenuation at 3 Hz decreases with depth from 0.45 dB/A at the sea floor to 0.15 dB/A at 60 m depth, with an approximately quadratic frequency dependence.
Report Number
CP-37Source
In: Selected papers on ocean-seismo acoustics low-frequency underwater acoustics (SACLANTCEN Conference Proceedings CP-37), 1986, pp. 5-1 - 5-10.Date
1986/06Author(s)
Jensen, Finn B.
; Schmidt, Henrik