### Abstract

Direct path measurements of a single-bottom interacting path on a vertical array are used to probe the seabed structure. The phase of the cross-spectrum, commonly used in engineering acoustics, permits examination of the importance of subbottom paths. When the cross-spectral phase is linear with frequency it implies that source to receiver propagation is dominated by a single path. A linear cross-spectral phase would also satisfy the linear seabed reflection coefficient phase approximation sometimes employed in forward modeling and geoacoustic inversion approaches. Shallow water measurements of the cross-spectrum, however, evidence a strongly nonlinear phase, below about 1500 Hz at one site, and 600 Hz at another site, implying that: 1) the subbottom structure plays an important role (i.e., a seabed half-space approximation would be inappropriate); and 2) the linear reflection phase approximation would be violated at those frequencies.

Original language | English (US) |
---|---|

Article number | 5766773 |

Pages (from-to) | 248-258 |

Number of pages | 11 |

Journal | IEEE Journal of Oceanic Engineering |

Volume | 36 |

Issue number | 2 |

DOIs | |

State | Published - Apr 1 2011 |

### Fingerprint

### All Science Journal Classification (ASJC) codes

- Ocean Engineering
- Electrical and Electronic Engineering
- Mechanical Engineering

### Cite this

*IEEE Journal of Oceanic Engineering*,

*36*(2), 248-258. [5766773]. https://doi.org/10.1109/JOE.2011.2114111

}

*IEEE Journal of Oceanic Engineering*, vol. 36, no. 2, 5766773, pp. 248-258. https://doi.org/10.1109/JOE.2011.2114111

**Cross-spectral analysis of midfrequency acoustic waves reflected by the seafloor.** / Guillon, Laurent; Holland, Charles; Barber, Christopher.

Research output: Contribution to journal › Review article

TY - JOUR

T1 - Cross-spectral analysis of midfrequency acoustic waves reflected by the seafloor

AU - Guillon, Laurent

AU - Holland, Charles

AU - Barber, Christopher

PY - 2011/4/1

Y1 - 2011/4/1

N2 - Direct path measurements of a single-bottom interacting path on a vertical array are used to probe the seabed structure. The phase of the cross-spectrum, commonly used in engineering acoustics, permits examination of the importance of subbottom paths. When the cross-spectral phase is linear with frequency it implies that source to receiver propagation is dominated by a single path. A linear cross-spectral phase would also satisfy the linear seabed reflection coefficient phase approximation sometimes employed in forward modeling and geoacoustic inversion approaches. Shallow water measurements of the cross-spectrum, however, evidence a strongly nonlinear phase, below about 1500 Hz at one site, and 600 Hz at another site, implying that: 1) the subbottom structure plays an important role (i.e., a seabed half-space approximation would be inappropriate); and 2) the linear reflection phase approximation would be violated at those frequencies.

AB - Direct path measurements of a single-bottom interacting path on a vertical array are used to probe the seabed structure. The phase of the cross-spectrum, commonly used in engineering acoustics, permits examination of the importance of subbottom paths. When the cross-spectral phase is linear with frequency it implies that source to receiver propagation is dominated by a single path. A linear cross-spectral phase would also satisfy the linear seabed reflection coefficient phase approximation sometimes employed in forward modeling and geoacoustic inversion approaches. Shallow water measurements of the cross-spectrum, however, evidence a strongly nonlinear phase, below about 1500 Hz at one site, and 600 Hz at another site, implying that: 1) the subbottom structure plays an important role (i.e., a seabed half-space approximation would be inappropriate); and 2) the linear reflection phase approximation would be violated at those frequencies.

UR - http://www.scopus.com/inward/record.url?scp=79957873755&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=79957873755&partnerID=8YFLogxK

U2 - 10.1109/JOE.2011.2114111

DO - 10.1109/JOE.2011.2114111

M3 - Review article

VL - 36

SP - 248

EP - 258

JO - IEEE Journal of Oceanic Engineering

JF - IEEE Journal of Oceanic Engineering

SN - 0364-9059

IS - 2

M1 - 5766773

ER -