Houtman Sub-basin 2D Seismic Survey 2014, (GA-0349/Duke10046) - High Resolution Bathymetry Grids

Full description

Geoscience Australia conducted a marine seismic survey (GA-0349) over poorly defined areas of the Houtman sub-basin (part of the Perth basin) between 15th of November to the 23rd of January 2015. The aim was to acquire high quality, industry-standard precompetitive 2D seismic data, Multi-beam echo-sounder (MBES) off the coast of Western Australia. The new seismic data will supplement existing geological knowledge of the region, underpin petroleum prospectivity evaluation and support the discovery of new oil gas resources.

This dataset is not to be used for navigational purposes.

Lineage

Maintenance and Update Frequency: asNeeded

Statement: The Houtman 2D 2014 Seismic Survey, GA-0349 Duke/10046 was acquired by Geoscience Australia onboard the MV Duke from the 15th of November 2014 to the 23th of January 2015. The Chief scientist was Dr. Irina Borissova. This dataset was acquired by CGG onboard the MV Duke and processed in the office by Michele Spinoccia, using CARIS HIPS & SIPS ver 7.1.2. 1. First a vessel configuration file was created where the co-ordinates of the motion sensor and DGPS antenna and patch test offsets were recorded. 2. A new project was then created and the vessel configuration file was attached to the project file. 3. The raw swath sonar data, in raw.all format, for each line was then imported into the project and the vessel information assigned to the data. 4. The motion sensor, DGPS and heading data were then cleaned using a filter that averaged adjacent data to remove artefacts. 5. Different sound velocity profiles data for each block were attached to the corresponding raw swath sonar data files to correct the depths for changes in the speed of sound through the water column. 6. Then a new blank field area was defined that specified the geographic area of study and the co-ordinate system used. The co-ordinates for the study areas were WGS84 UTM-49S and 50S. 7. The data was cleaned by applying several filters that removed any remaining spikes in the bathymetry data using user defined threshold values. A visual inspection of the data for each line was then undertaken where artefacts and noisy data not removed by the filtering process were removed manually using Swath and subset editors modules of the Caris HIPS/SIPS software. 8. All the data for each bathymetric, motion sensor, DGPS, heading, tide and sound velocity profile data were merged to produce the final processed data file. A weighted grid of the processed data was then created for each Block. In GA the tide was applied to the grid to correct for tidal variations and velocity corrections were performed to correct for different artefacts and mismatches. 9. The processed data was finally exported as grids soundings or false colored images for presentation and reporting and as final processed data in ASCII XYZ as well as geotif formats of 15 and 25m resolution. 10-Using CARIS Base editor 4.0 the grids were exported as ESRI ASCII grid, then imported into ARC catalogue/info to create a raster file for the entire survey.