Oceanic Shoals Commonwealth Marine Reserve - High Resolution Multibeam Acoustic Backscatter Grids  

Authors / CoAuthors

Siwabessy, J. | Picard, K.

Abstract

This resource contains bathymetry and backscatter data for the Oceanic Shoals Commonwealth Marine Reserve (CMR) in the Timor Sea collected by Geoscience Australia during September and October 2012 on RV Solander (survey GA0339/SOL5650). The survey used a Kongsberg EM3002 300 kHz multibeam sonar system mounted in single head configuration to map four areas, covering a combined area of 507 square kilometres. Data are gridded to 2 m spatial resolution. The Oceanic Shoals Commonwealth Marine Reserve survey was undertaken as an activity within the Australian Government's National Environmental Research Program Marine Biodiversity Hub and was the key component of Research Theme 4 - Regional Biodiversity Discovery to Support Marine Bioregional Plans. Hub partners involved in the survey included the Australian Institute of Marine Science, Geoscience Australia, the University of Western Australia, Museum Victoria and the Museum and Art Gallery of the Northern Territory. Data acquired during the survey included: multibeam sonar bathymetry and acoustic backscatter; sub-bottom acoustic profiles; physical samples of seabed sediments, infauna and epibenthic biota; towed underwater video and still camera observations of seabed habitats; baited video observations of demersal and pelagic fish, and; oceanographic measurements of the water column from CTD (conductivity, temperature, depth) casts and from deployment of sea surface drifters. Further information on the survey is available in the post-survey report published as Geoscience Australia Record 2013/38 (Nichol et al. 2013).

Product Type

dataset

eCat Id

79007

Contact for the resource

Keywords

• Marine DataBackscatter Grid

( Theme )

• backscatter

( Theme )

• geoscience

( Theme )

• marine environmental baselines

( Theme )

• multibeam

( Theme )

• NERP Marine Biodiversity Hub

( Theme )

• marine

( Theme )

• NERP

• AU-WA

Australian and New Zealand Standard Research Classification (ANZSRC)

• Environmental Sciences

• Published_External

Publication Date

2014-01-01T00:00:00

Creation Date

Security Constraints

Australian Government Security ClassificationSystem    

Classification - unclassified

Legal Constraints

Creative Commons Attribution-NonCommercial 4.0 International Licence    

Access - license

Use - license

Status

Purpose

Maintenance Information

asNeeded

Topic Category

geoscientificInformation

Series Information

Lineage

The backscatter data were processed using CMST-GA MB Process v10.10.17.0 software. The fully processed backscatter strengths were corrected for transmission loss and insonification area. The process within the toolbox also involved removal of the system transmission loss, removal of the system model, calculation of the incidence angle and removal of the angular dependence. The grid values are basically the average values of the processed backscatter point data within each grid cell of predefined size, normalised to the backscatter strength at an angle of 25 degrees.

Parent Information

Extents

[-12.23, -11.31, 126.89, 127.48]

Reference System

Spatial Resolution

Service Information

Associations

Downloads and Links

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Source Information

Data was sourced from the NERP Marine Biodiversity Hub. The Marine Biodiversity Hub is supported through funding from the Australian Government's National Environmental Research Program (NERP), administered by the Department of Sustainability, Environment, Water, Population and Communities (DSEWPAC). Processing software: CMST-GA MB Process v10.10.17.0 Survey Name: Oceanic Shoals Marine Surveys GA-0339/SOL5650 Vessel: RV Solander Country: Australia Operator: AIMS Bathymetric system used: Kongsberg EM3002 Year of installation: 2012 Nominal sonar frequency: 300 kHz Number of beams: 160 beams Beamwidth across track: 1.5 degrees Beamwidth along track : 1.5 degrees Pulse length: Variable, operator selectable Depth range: 40 - 190 m Vessel speed: 8 - 10 knots Start date of survey: 12 September 2012 End date of survey: 06 October 2012 Institution: AIMS & Geoscience Australia Start port: Broome End port: Broome Survey leaders: Scott Nichol Data acquired and processed by: Justy Siwabessy, Kim Picard, Ian Atkinson Grids resolution: 2m Number of grids: 4 This dataset consists of the following files: - Georeferenced colour tif images in 2m resolution, shaded with sun azimuth 45 degrees - ASCII xyz (*.txt) grids in 2m resolution in UTM52S WGS84 - ESRI ascii (*.asc) grids in 2m resolution in UTM52S WGS84 - ESRI Rasters in 2m resolution - KMZ files