Multiple Scatter Theory of Ocean Sediments II
Abstract
It is postulated that a laminar sand bed may be modeled as an ensemble of randomly layered poroelastic material. The thickness of each layer was related to the associated grain size and porosity by a conservation of mass relationship. The effect of lateral variations in grain size were simulated by performing a coherent ensemble average of results from several realizations of the randomly stratified medium. Poroelastic medium parameters were chosen to represent water saturated sand. The mean and standard deviation of the grain size distribution were chosen to match existing experimental data. Specifically, the sand bed was modeled as bounded by a homogeneous water halfspace above, and a homogeneous poroelastic halfspace of equivalent average porosity below. Reflected and transmitted signals were computed. Coherent and random components of the reflected signal were calculated. The coherent parts were directly related to the reflected and the transmitted waves. Results show significant differences between the modeled sand bed and an equivalent uniform Biot medium. The fast wave attenuation shows strong anisotropy. The slow wave is only detectable in the sand bed at shallow grazing angles.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 16, 1998
- Accession Number
- ADA335476
Entities
People
- Nicholas P. Chotiros
Organizations
- University of Texas at Austin