Fine-Scale Volume Heterogeneity in a Mixed Sand/Mud Sediment Off Fort Walton Beach, FL

Abstract

As part of the effort to characterize the acoustic and physical properties of the seafloor during the high-frequency 2004 Sediment Acoustics Experiment (SAX04), fine-scale variability of sediment sound speed and density was measured in a medium quartz sand using diver cores and an in situ conductivity probe. This study has a goal of providing environmental input to high-frequency backscatter modeling efforts. Because the experiment was conducted immediately following exposure of the site to Hurricane Ivan, measurements revealed storm-generated sedimentary structure that included mud deposits and trapped sand pockets suspended in the mud. Fluctuations of sediment sound speed and density were measured downcore at 1- and 2-cm increments, respectively, with standard laboratory techniques. Sediment density was also measured on a very fine scale with an in situ conductivity probe [in situ measurement of porosity (IMP2)] and by means of computed tomography (CT) imaging of a diver core. Overlap between the locations of the diver cores and the conductivity probe measurements allowed an examination of multiple scales of sediment heterogeneity and a comparison of techniques.

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 2010
Accession Number
ADA528937

Entities

People

  • Allen H. Reed
  • Dajun Tang
  • Darrell R. Jackson
  • Kevin B. Briggs

Organizations

  • United States Naval Research Laboratory

Tags

Communities of Interest

  • Energy and Power Technologies
  • Sensors

DTIC Thesaurus Topics

  • Acoustic Measurement
  • Acoustic Properties
  • Acoustics
  • Backscattering
  • Conductivity
  • Data Sets
  • Detectors
  • Engineering
  • Grain Size
  • High Resolution
  • Measurement
  • Physical Properties
  • Physics Laboratories
  • Power Spectra
  • Scattering
  • Three Dimensional
  • X-Ray Computed Tomography

Readers

  • Acoustical Oceanography.
  • Coastal Oceanography
  • Geotechnical Engineering.