|
|
|
|
| |
|
| |
|
|
| Guillon, Laurent; Lurton, Xavier. |
| Signals received by low-frequency multibeam echosounders are strongly affected by sound penetration inside the upper sediment layers and by backscattering from buried layers down to depths of a few meters; this may lead to serious ambiguities and misinterpretations of experimental data. These phenomena are modeled here using a concept of equivalent input backscattering strength (EIBS), based on a combination of classical models of local backscattering strength and propagation inside fluid layered media. The local backscattering strength at a buried interface is expressed first to account for the impedance adaptation due to the overlying layers, for the angular refraction effects due to the velocity profile, and for the layered structure of the underlying... |
| Tipo: Text |
Palavras-chave: Sound propagation; Sediment structure; Multibeam sonar; Echosounding; Backscatter; Acoustic properties; Sediment properties. |
| Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/publication-729.pdf |
| |
|
| |
|
|
| De Mello, C.; López-Orrego, G.. |
| Se analizaron los datos hidroacústicos obtenidos con la ecosonda multihaz Simrad EM-302 a bordo del B/O Miguel Oliver en la campaña 01-2010 durante enero-febrero de 2010. El objetivo fue mapear el fondo oceánico de parte de la plataforma y talud de la Zona Económica Exclusiva (ZEE) uruguaya. El procesamiento fue realizado mediante los softwares libres MB-System y GRASS GIS. Con los datos corregidos se obtuvieron grillas de 3 X 3 m para describir las formaciones del fondo y de 1/8mn x 1/8mn para realizar un mapa topográfico y otro batimétrico (con isóbatas cada 100 m) de toda el área de estudio. Se realizó además una base de datos de las principales formaciones observadas (elevaciones y depresiones) conteniendo imágenes, posición y dimensiones (altura... |
| Tipo: Preprint |
Palavras-chave: Multibeam sonar; Seafloor mapping; Submarine canyons; Coral reefs. |
| Ano: 2011 |
URL: http://hdl.handle.net/1834/4376 |
| |
|
|
| López-Orrego, Guzmán; De Mello, Camila; Marín, Yamandú. |
| We analyzed the acoustic data obtained with a multibeam echosounder during an oceanographic survey abroad the “R/V Miguel Oliver” in january-february of 2010. The aim was mapping the sea floor of the continental slope of the uruguayan Exclusive Economic Zone (EEZ). The acoustic data were processed with MB-System software, and then incorporated into a Geographic Information System (Quantum GIS). We obtained 3 m for 3 m grid files to describe small submarine structures (mounds and pockmarks), and also a topographic map of the entire area to describe large submarine structures (submarine canyons and landslides). When we analyzed the topography of the entire area we identified 4 submarine canyons and the beginning of a fifth in the south end. We also observed... |
| Tipo: Proceedings Paper |
Palavras-chave: Multibeam sonar; Seafloor mapping; Submarine canyons; Coral reefs. |
| Ano: 2011 |
URL: http://hdl.handle.net/1834/4336 |
| |
|
|
|
