Seabed environments and shallow geology of the Leveque Shelf, Browse Basin, Western Australia - interpreted geomorphic map

Brief description

In May 2013, Geoscience Australia (GA) and the Australian Institute of Marine Science (AIMS) undertook a collaborative seabed mapping survey (GA0340/ SOL5754) on the Leveque Shelf, a distinct geological province within the Browse Basin, offshore Western Australia. The purpose of the survey was to acquire geophysical and biophysical data on seabed environments over a previously identified potential CO2 injection site to better understand the overlying seabed habitats and to assess potential for fluid migration to the seabed.

Mapping and sampling was undertaken across six areas using multibeam and single beam echosounders, sub-bottom profilers, sidescan sonar, underwater towed-video, gas sensors, water column profiler, grab samplers, and vibrocorer. Over 1070 km2 of seabed and water column was mapped using the multibeam and single beam echosounder, in water depths ranging between 40 and 120 m. The sub-surface was investigated using the multichannel and the parametric sub-bottom profilers along lines totalling 730 km and 1547 km in length respectively. Specific seabed features were investigated over 44 line km using the sidescan sonar and physically and sampled at 58 stations.

Integration of this newly acquired data with existing seismic data will provide new insights into the geology of the Leveque Shelf. This work will contribute to the Australian Government's National CO2 Infrastructure Plan (NCIP) by providing key seabed environmental and geological data to better inform the assessment of the CO2 storage potential in this area of the Browse Basin.

This catalogue entry refers to an interpreted geomorphic map, mapped at 1:10 000 scale. Geomorphic mapping was completed using a combination of semi-automated feature extraction and hand digitisation from bathymetry and backscatter grids collected during the survey along with their derivatives and reference to broader scale geomorphic maps (Heap and Harris, 2008).

Lineage

Maintenance and Update Frequency: asNeeded

Statement: This dataset was hand digitised using the Leveque Shelf, Browse Basin Marine Environemnetal Survey - High Resolution Bathymetry Grids. The criteria used to define each geomorphic unit is documented in the associated geomorphic mapping method document. This map was produced at a scale of 1:10 000.