+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Quantitative characterisation of seafloor substrate and bedforms using advanced processing of multibeam backscatter; application to Cook Strait, New Zealand

Quantitative characterisation of seafloor substrate and bedforms using advanced processing of multibeam backscatter; application to Cook Strait, New Zealand

Continental Shelf Research 31.2, Suppl.

A comprehensive EM300 multibeam echo-sounder dataset acquired from Cook Strait, New Zealand, is used to develop a regional-scale objective characterisation of the seafloor. Sediment samples and high-resolution seismic data are used for ground-truthing. SonarScope(R) software is used to process the data, including signal corrections from sensor bias, specular reflection compensation and speckle noise filtering aiming at attenuating the effects of recording equipment, seafloor topography, and water column. The processing is completed by correlating a quantitative description (the Generic Seafloor Acoustic Backscatter-GSAB model) with the backscatter data. The calibrated Backscattering Strength (BS) is used to provide information on the physical characteristics of the seafloor. The imagery obtained from the BS statistical compensation is used for qualitative interpretation only; it helps characterizing sediment facies variations as well as geological and topographic features such as sediment waves and erosional bedforms, otherwise not recognised with the same level of detail using conventional surveying. The physical BS angular response is a good indicator of the sediment grain size and provides a first-order interpretation of the substrate composition. BS angular response for eight reference areas in the Narrows Basin are selected and parameterised using the GSAB model, and BS angular profiles for gravelly, sandy, and muddy seafloors are used as references for inferring the grain size in the reference areas. We propose to use the calibrated BS at 45 degrees incidence angle (BS(45) ) and the Specular-To-Oblique Contrast (STOC) as main global descriptors of the seafloor type. These two parameters enable global backscatter studies by opposition to compensated imagery whose intensity is not comparable from one zone to the other. The results obtained highlight the interest of BS measurements for seafloor remote sensing in a context of habitat-mapping applications.

Please choose payment method:

(PDF emailed within 0-6 h: $19.90)

Accession: 037137549

Download citation: RISBibTeXText

DOI: 10.1016/j.csr.2010.06.001

Related references

Acoustical characterisation of seafloor sediments and its relationship to active sedimentary processes in Cook Strait, New Zealand. New Zealand Journal of Geology and Geophysics 35(3): 289-300, 1992

Regional substrate classification of Cook Strait, New Zealand, from textural image analysis of backscatter data. Bulletin of the Geological Society of Finland (Painettu) 83.Special Issue 1: 61, 2011

Imaging active and relict seafloor methane seep sites; a comparison of seafloor 3D seismic reflectivity and multibeam sonar backscatter intensity at Omakere Ridge, Hikurangi margin, New Zealand. American Geophysical Union Fall Meeting, 2011

Seafloor classification of the mound and channel provinces of the Porcupine Seabight; an application of the multibeam angular backscatter data. International Journal of Earth Sciences 96(1): 11-20, 2007

Unsupervised fuzzy classification and object-based image analysis of multibeam data to map deep water substrates, Cook Strait, New Zealand. Continental Shelf Research 31(11): 0-1247, 2011

Initial results from seafloor characterization of Arctic and Antarctic margins using multibeam backscatter. Oulu, Finland (FIN): University of Oulu, 2012

Seafloor stability along the Cook Strait power cable corridor. Water Quality Centre Publication 21(Pages 565-570, 1991

Re-examination of sand ridges on the middle and outer New Jersey shelf based on combined analysis of multibeam bathymetry and backscatter, seafloor grab samples and chirp seismic data. Special Publication of the International Association of Sedimentologists 44: 121-142, 2012

Characterisation of seafloor substrates using EM300 backscatter strength. 2003

Seafloor characterisation and habitat mapping using backscatter reflectivity data. Newsletter - New Zealand Geophysical Society 72(Pages 18-24, 2006

Procellariiformes in Cook Strait, New Zealand. Emu, 69: 155-160, 1969

New Zealand coelenterates. Ctenophores from Cook Strait. Victoria Univ Coll Zool Publ 3: 1-11, 1950

The holothurian fauna of Cook Strait, New Zealand. Zool Publ Victoria Univ Wellington 36: 1-38, 1963

Some additional New Zealand cephalopods from Cook Strait. Zool Publ Victoria Univ 25: 1-12, 1959

Cook Strait, New Zealand; a new frontier basin. Petroleum Exploration Society of Australia Special Publication 1(Pages 159-166, 2001