Constraints on Crustal Structure from Long Period Pressure and Displacement Measurements on the Deep Seafloor
Abstract
Accurate estimates of seafloor shear and compressional velocities are essential for modelling long range acoustic propagation within the ocean. Compressional wave velocities have been measured using seismic refraction techniques for decades, however shallow seafloor structure is poorly resolved with sources and receivers located near the sea surface. Shear velocity is poorly known at all depths; since the ocean does not support shear propagation, only converted waves are observable at the sea surface. At MPL we have developed instrumentation capable of measuring the very small seafloor deformations resulting from very low frequency surface gravity waves (infragravity waves). By measuring a number of sites we will study the elastic changes associated with aging of the oceanic crust. We investigated the inverse problem associated with this technique which allows a quantitative connection between measured seafloor transfer functions and the elastic properties of the shallow crust. Ocean-bottom microseismicity, Seafloor shear and compressional velocities, Seafloor compliance.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1993
- Accession Number
- ADA269931
Entities
People
- Spahr C. Webb
Organizations
- Scripps Institution of Oceanography