Velocity and Attenuation Profiles in the Monterey Deep-Sea Fan
Abstract
Data obtained during a refraction experiment is used to estimate velocity and attenuation profiles in an area of thick sediments (2.5 -3 km). A vertical hydrophone array was deployed at mid-depth in 2800 meters of water. Estimates of velocity as a function of depth, and attenuation as a function of frequency and depth are obtained from an analysis of the pressure time series generated by the explosive charges and received at the array. To find the velocity profile, the sediment is modeled as a horizontally layered, laterally homogeneous medium. A least squares solution is found for the velocity gradients in each layer of the model. Velocity as a function of depth is obtained by integrating these gradients. A second method to infer velocity structure using linear programming takes upper and lower bounds on the input data and gives as a solution upper and lower bounds on the velocity profile. All velocity profiles consistent with the data lie within these bounds. Using a similar sediment model, a method of spectral ratios estimates attenuation in the sediment as a function of frequency and depth. Solving for each of the coefficients gives attenuation as a function of depth.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1987
- Accession Number
- ADA193235
Entities
People
- Richard K. Brienzo
Organizations
- Scripps Institution of Oceanography