KN145L4 Perth Canyon Bathymetry 1994 (1179/19940008S)

Full description

The KN145L4 bathymetry survey was acquired by the Woods Hole Oceanographic Institution onboard the Woods Hole Oceanographic Institution (WHOI) Research Vessel Knorr from the 19 November to 22 November 1994 using the SeaBeam 2112 sonar system. The bathymetry dataset was acquired while the Research Vessel Knorr was surveying the Perth Canyon in Australia.

This dataset contains the 128-210m resolution, 32-bit geotiffs of the KN145L4 survey produced from the processed SeaBeam system using the CARIS HIPS and SIPS software.

Appropriate acknowledgment must be given to both the Dr. (Purdy, G. M.) (http://www.marine-geo.org/tools/search/entry.php?id=KN145L4#datasets) and to the Marine Geoscience Data System (www.marine-geo.org).

Not to be used for navigational purposes

Lineage

Maintenance and Update Frequency: asNeeded

Statement: The KN145L4, was acquired by the Columbia University onboard the Woods Hole Oceanographic Institution onboard the Woods Hole Oceanographic Institution (WHOI) Research Vessel Knorr during the period of the 19 November to 22 November 1994. The Chief Scientist onboard during the transit was Dr. Mike Purdy. This dataset was acquired and processed onboard by Woods Hole Oceanographic Institution (WHOI) and further processing was conducted in Geoscience Australia by Michele Spinoccia, using CARIS HIPS & SIPS ver 7.1.2. For any metadata questions, please download the Metadata.txt file with the dataset. Processing: 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 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-UTMXXS. 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 32bit geotiff format at the optimum resolution the data can provide.

Notes

Purpose
To derive seabed information for the purpose of supporting the sustainable use of our marine environment and jurisdiction; strengthening our resilience to natural hazards and enabling location-based decisions and actions through best practice digital mapping, Earth observations and precise positioning.