Authors / CoAuthors
Howard, F.J.F. | Thun, C.
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 grain size data and carbonate concentrations of the upper ~2cm of seabed sediment. Sediment samples were first wet sieved to determine the proportions of mud, sand and gravel as a percentage. By wet sieving fine particles are removed from the sand and gravel fractions, allowing an accurate measurement each component. The mud, sand, gravel percentages were also used to derive Folk sediment texture classifications for each sample (Folk, 1980). The grain size of the mud fraction (<63 m) was determined using a Mastersizer laser granulometer. Sediment > 63 um diameter were dried, and dry sieved at values between 4 and -4 phi corresponding to the Wentworth (1922) grain size boundaries between the major sediment classes. The samples were then submitted for measurement of carbonate content by mass using the carbonate digestion method described in Müller and Gastner (1971).
Product Type
dataset
eCat Id
89782
Contact for the resource
Custodian
Owner
Custodian
Cnr Jerrabomberra Ave and Hindmarsh Dr GPO Box 378
Canberra
ACT
2601
Australia
Keywords
-
- Data Package
- ( Theme )
-
- geological storage of CO2
- ( Theme )
-
- marine survey
- ( Theme )
-
- marine environmental baselines
- ( Theme )
-
- Exclusive Economic Zone
- ( Theme )
-
- sedimentology
-
- Australian EEZ
- Australian and New Zealand Standard Research Classification (ANZSRC)
-
- Marine Geoscience
-
- Published_External
Publication Date
2016-06-07T12:00:00
Creation Date
2015-01-01T00:00:00
Security Constraints
Legal Constraints
Status
Purpose
Maintenance Information
notPlanned
Topic Category
oceans
Series Information
Lineage
Version 1
Parent Information
Extents
[-14.29, -12.8678, 122.39, 124.6521]
Reference System
Spatial Resolution
Service Information
Associations
Source Information
Dataset collected in WGS84. Source extent for the metadata record however is in GDA94 to be consistent with other source extents for GA products. 122.38883 124.6521 -14.2865 -12.8678