Strong bragg scattering of low-frequency sound from a line source in shallow water. I: One uniform surface wave

Charles Holland, Greg Muncill

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

A useful theoretical measure of acoustic interaction with the seafloor is the plane wave reflection coefficient (J?), which is commonly expressed as bottom loss (—20log ᴵ R ᴵ). Predictions indicate that when the seafloor is modeled as a refracting layer over a basement half-space, the bottom loss is proportional to frequency. Bottom loss measurements in the 50-1600-Hz b, however, frequently show a loss that is inversely proportional to frequency. For example, roughly one-third of a set of measured bottom loss data in the North Atlantic exhibit this anomalous frequency dependence. It is concluded that the anomalous frequency dependence is due to sedimentary fine-scale layering arising from turbidity currents. The evidence presented consists of (1) a high correlation between the anomalous bottom loss stations and the bounds of the abyssal plains and (2) favorable predictions between a model accounting for the layering and the measured data. The study area was the western North Atlantic including the Sohm, Hatteras, and Nares abyssal plains. A simple, approximate stochastic model of reflection from a quasiperiodic sedimentary sequence was developed that appears to account for the dominant physical mechanisms important in the reflection process in this type of physiographic province.

Original languageEnglish (US)
Pages (from-to)1609-1620
Number of pages12
JournalJournal of the Acoustical Society of America
Volume94
Issue number3
DOIs
StatePublished - Jan 1 1993

Fingerprint

shallow water
surface waves
low frequencies
acoustics
scattering
plains
wave reflection
turbidity
half spaces
predictions
basements
Water
Waves
Sound
plane waves
stations
reflectance
interactions

All Science Journal Classification (ASJC) codes

  • Acoustics and Ultrasonics
  • Arts and Humanities (miscellaneous)

Cite this

@article{333e47794a3849c88b3bbe912a1ea489,
title = "Strong bragg scattering of low-frequency sound from a line source in shallow water. I: One uniform surface wave",
abstract = "A useful theoretical measure of acoustic interaction with the seafloor is the plane wave reflection coefficient (J?), which is commonly expressed as bottom loss (—20log ᴵ R ᴵ). Predictions indicate that when the seafloor is modeled as a refracting layer over a basement half-space, the bottom loss is proportional to frequency. Bottom loss measurements in the 50-1600-Hz b, however, frequently show a loss that is inversely proportional to frequency. For example, roughly one-third of a set of measured bottom loss data in the North Atlantic exhibit this anomalous frequency dependence. It is concluded that the anomalous frequency dependence is due to sedimentary fine-scale layering arising from turbidity currents. The evidence presented consists of (1) a high correlation between the anomalous bottom loss stations and the bounds of the abyssal plains and (2) favorable predictions between a model accounting for the layering and the measured data. The study area was the western North Atlantic including the Sohm, Hatteras, and Nares abyssal plains. A simple, approximate stochastic model of reflection from a quasiperiodic sedimentary sequence was developed that appears to account for the dominant physical mechanisms important in the reflection process in this type of physiographic province.",
author = "Charles Holland and Greg Muncill",
year = "1993",
month = "1",
day = "1",
doi = "10.1121/1.408134",
language = "English (US)",
volume = "94",
pages = "1609--1620",
journal = "Journal of the Acoustical Society of America",
issn = "0001-4966",
publisher = "Acoustical Society of America",
number = "3",

}

Strong bragg scattering of low-frequency sound from a line source in shallow water. I : One uniform surface wave. / Holland, Charles; Muncill, Greg.

In: Journal of the Acoustical Society of America, Vol. 94, No. 3, 01.01.1993, p. 1609-1620.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Strong bragg scattering of low-frequency sound from a line source in shallow water. I

T2 - One uniform surface wave

AU - Holland, Charles

AU - Muncill, Greg

PY - 1993/1/1

Y1 - 1993/1/1

N2 - A useful theoretical measure of acoustic interaction with the seafloor is the plane wave reflection coefficient (J?), which is commonly expressed as bottom loss (—20log ᴵ R ᴵ). Predictions indicate that when the seafloor is modeled as a refracting layer over a basement half-space, the bottom loss is proportional to frequency. Bottom loss measurements in the 50-1600-Hz b, however, frequently show a loss that is inversely proportional to frequency. For example, roughly one-third of a set of measured bottom loss data in the North Atlantic exhibit this anomalous frequency dependence. It is concluded that the anomalous frequency dependence is due to sedimentary fine-scale layering arising from turbidity currents. The evidence presented consists of (1) a high correlation between the anomalous bottom loss stations and the bounds of the abyssal plains and (2) favorable predictions between a model accounting for the layering and the measured data. The study area was the western North Atlantic including the Sohm, Hatteras, and Nares abyssal plains. A simple, approximate stochastic model of reflection from a quasiperiodic sedimentary sequence was developed that appears to account for the dominant physical mechanisms important in the reflection process in this type of physiographic province.

AB - A useful theoretical measure of acoustic interaction with the seafloor is the plane wave reflection coefficient (J?), which is commonly expressed as bottom loss (—20log ᴵ R ᴵ). Predictions indicate that when the seafloor is modeled as a refracting layer over a basement half-space, the bottom loss is proportional to frequency. Bottom loss measurements in the 50-1600-Hz b, however, frequently show a loss that is inversely proportional to frequency. For example, roughly one-third of a set of measured bottom loss data in the North Atlantic exhibit this anomalous frequency dependence. It is concluded that the anomalous frequency dependence is due to sedimentary fine-scale layering arising from turbidity currents. The evidence presented consists of (1) a high correlation between the anomalous bottom loss stations and the bounds of the abyssal plains and (2) favorable predictions between a model accounting for the layering and the measured data. The study area was the western North Atlantic including the Sohm, Hatteras, and Nares abyssal plains. A simple, approximate stochastic model of reflection from a quasiperiodic sedimentary sequence was developed that appears to account for the dominant physical mechanisms important in the reflection process in this type of physiographic province.

UR - http://www.scopus.com/inward/record.url?scp=0027302797&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0027302797&partnerID=8YFLogxK

U2 - 10.1121/1.408134

DO - 10.1121/1.408134

M3 - Article

AN - SCOPUS:0027302797

VL - 94

SP - 1609

EP - 1620

JO - Journal of the Acoustical Society of America

JF - Journal of the Acoustical Society of America

SN - 0001-4966

IS - 3

ER -