Authors / CoAuthors
Siwabessy, P.J.W.
Abstract
This resource contains a multibeam backscatter grid for the greater Darwin Harbour region as part of a baseline seabed mapping program of Darwin Harbour and Bynoe Harbour. This project was funded through offset funds provided by an INPEX-led Ichthys LNG Project to the Northern Territory Government’s Department of Environment and Natural Resources (NTG-DENR) with co-investment from Geoscience Australia (GA) and the Australian Institute of Marine Science (AIMS). The intent of this program is to improve knowledge of the marine environments in the Darwin and Bynoe Harbour regions by collating and collecting baseline data that enable the creation of thematic habitat maps and information to underpin marine resource management decisions. The backscatter grid was derived from a compilation of multiple surveys undertaken by GA, AIMS and NTG-DENR between 2011 and 2017, including GA0333 (Siwabessy et al., 2015), GA0341 (Siwabessy et al., 2015), GA0351/SOL6187 (Siwabessy et al., 2016), GA4452/SOL6432 (Siwabessy et al., 2017), GA0356 (Radke et al., 2017), and GA0358 and GA0359 (Radke et al., 2018), adding to those from a previous survey GA0333 collected by GA, AIMS and NTG-DENR.
Product Type
dataset
eCat Id
127102
Contact for the resource
Point of contact for the resource
Point of contact
Point of contact
Cnr Jerrabomberra Ave and Hindmarsh Dr GPO Box 378
Canberra
ACT
2601
Australia
Keywords
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- Backscatter
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- Marine Environmental Baselines
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- Marine Survey
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- Exclusive Economic Zone
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- Published_External
Publication Date
2020-01-15T02:58:52
Creation Date
Security Constraints
Legal Constraints
Status
completed
Purpose
Maintenance Information
asNeeded
Topic Category
geoscientificInformation
Series Information
Lineage
This backscatter grid composed of multibeam sonar data from multiple surveys GA4425 in 2010, GA0333 in 2011, GA0351/SOL6187 in 2015, GA4452/SOL6432 in 2016, GA0361 in 2017 and GA0362 in 2017 and 2018. The first two surveys were acquired by Geoscience Australia (GA), Australian Institute of Marine Science (AIMS), Northern Territory Government’s Department of Environment and Natural Resources (NTG-DENR) and Darwin Port Authority using GA’s Kongsberg EM3002D multibeam echosounder from aboard MV Matthew Flinders and the last four surveys by GA, AIMS and NTG-DENR using GA’s Kongsberg EM2040C Dual multibeam echosounder from aboard RV Solander for the first two and using GA’s Kongsberg EM3002D from aboard MV Reelax and RV Capricornus for the last two respectively. These data were processed on the National Computational Infrastructure (NCI) supercomputer at the Australian National University using the CMST-GA MB Process v15.04.04.0 (64) toolbox software co-developed by the Centre for Marine Science and Technology (CMST) at Curtin University and GA (described in Gavrilov et al., 2005; Parnum and Gavrilov, 2011). The process involved removal of the system transmission loss, removal of the system model, calculation of the incidence angle, correction of the beam pattern, calculation of the angular backscatter response within a sliding window of 100 pings with a 50% overlap in a 1° bin, removal of the angular dependence, and restoration to the backscatter intensity at an angle of 40° (Siwabessy et al., 2015; 2016; 2017; 2018). The final processed data were gridded to 1 m horizontal resolution, then exported as gridded surface and converted to backscatter maps for further analysis in ArcGIS.
Parent Information
Extents
[-12.77, -12.1, 130.25, 131]
Reference System
WGS 84 / UTM zone 52S (EPSG:32752)
Spatial Resolution
1m
Service Information
Associations
Downloads and Links
Source Information