Authors / CoAuthors
Siwabessy, J.
Abstract
Geoscience Australia (GA) conducted a marine survey (GA0345/GA0346/TAN1411) of the north-eastern Browse Basin (Caswell Sub-basin) between 9 October and 9 November 2014 to acquire seabed and shallow geological information to support an assessment of the CO2 storage potential of the basin. The survey, undertaken as part of the Department of Industry and Science's National CO2 Infrastructure Plan (NCIP), aimed to identify and characterise indicators of natural hydrocarbon or fluid seepage that may indicate compromised seal integrity in the region. The survey was conducted in three legs aboard the New Zealand research vessel RV Tangaroa, and included scientists and technical staff from GA, the NZ National Institute of Water and Atmospheric Research Ltd. (NIWA) and Fugro Survey Pty Ltd. Shipboard data (survey ID GA0345) collected included multibeam sonar bathymetry and backscatter over 12 areas (A1, A2, A3, A4, A6b, A7, A8, B1, C1, C2b, F1, M1) totalling 455 km2 in water depths ranging from 90 - 430 m, and 611 km of sub-bottom profile lines. Seabed samples were collected from 48 stations and included 99 Smith-McIntyre grabs and 41 piston cores. An Autonomous Underwater Vehicle (AUV) (survey ID GA0346) collected higher-resolution multibeam sonar bathymetry and backscatter data, totalling 7.7 km2, along with 71 line km of side scan sonar, underwater camera and sub-bottom profile data. Twenty two Remotely Operated Vehicle (ROV) missions collected 31 hours of underwater video, 657 still images, eight grabs and one core. This catalogue entry refers to p-rock (probability of rock) grids produced from the angular response curves from the multibeam backscatter data. The extraction of angular response curves from the raw Simrad multibeam data was achieved using the multibeam backscatter CMST-GA MB Process v10.10.17.0 toolbox software co-developed by the Centre for Marine Science and Technology (CMST) at Curtin University of Technology and Geoscience Australia (described in Gavrilov et al., 2005a, 2005b; Parnum, 2007). A number of corrections were introduced to the data and the angular response curves were produced as the average response curve within the adopted sliding windows in which port and starboard swath were processed separately as part of the process of the removal of the backscatter angular dependence. Angular backscatter response curves were compared to the reference response of rock/hard bottom (inferred grabs and cores) using the Kolmogorov-Smirnov goodness of fit to estimate the probability (p-value) of rock (p-rock). Finally, the IDW interpolation technique was used to produce a continuous layer of the p-value of hard bottom for each study area.
Product Type
dataset
eCat Id
83920
Contact for the resource
Custodian
Owner
Custodian
Cnr Jerrabomberra Ave and Hindmarsh Dr GPO Box 378
Canberra
ACT
2601
Australia
Keywords
- ( Theme )
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- Exclusive Economic Zone
- ( Theme )
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- backscatter
- ( Theme )
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- marine environmental baselines
- ( Theme )
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- marine survey
- ( Theme )
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- geological storage of CO2
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- Australian EEZ
- Australian and New Zealand Standard Research Classification (ANZSRC)
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- Marine Geoscience
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- Published_External
Publication Date
2016-06-06T14:00:00
Creation Date
2015-01-01T00:00:00
Security Constraints
Legal Constraints
Status
Purpose
Maintenance Information
asNeeded
Topic Category
oceans
Series Information
Record
Lineage
Version 1
Parent Information
Extents
[-14.2865, -12.8678, 122.3883, 124.6521]
Reference System
Spatial Resolution
Service Information
Associations
Downloads and Links
Source Information
Datasets collected and in WGS84 UTM 51 S, extent indicator for the metadata record however is in GDA94 to be consistent with other national scale metadata records. The multibeam bathymetry was acquired by the following survey: - Processing software: CMST-GA MB Process v14.10.04.0 - Survey Name: Browse Basin 2014 Marine Survey (GA0345/TAN1411) - Vessel Name: RV Tangaroa - Institution: Geoscience Australia - Country: Australia - Operator: NIWA - Multibeam system: Kongsberg EM302 - Year of installation: Unknown - Nominal sonar frequency: 30 kHz - Number of beams: 288 beams - Max number of soundings: 432 - Beamwidth across track: Unknown - Beamwidth along track: Unknown - Pulse length: variable - Selectable depth range: Unknown - Vessel speed: 7 - 8 knots - Start Date: 09/10/2014 - End Date: 11/11/2014 - Start Port: Darwin - End Port: Darwin - Number of grids: 12 - Total surface coverage: 455 Km2 - Vertical Datum: MSL - Horizontal Datum: WGS84-51S - Survey leaders: Chris Nicholson - Data acquired and processed by: NIWA, Justy Siwabessy - Grids resolution: 10m - This dataset consist of the following files: + Georeferenced colour tif image in 10m resolution, shaded with sun azimuth 45 degrees + ESRI ascii (*.asc) in 10m resolution + ASCII xyz (*.txt) in 10m resolution + ESRI Raster in 10m resolution + KMZ file 122.3883 124.6521 -14.2865 -12.8678