Flinders Commonwealth Marine Reserve - Shelf Bathymetry Data  

Authors / CoAuthors

Atkinson, I. | Carey, M. | Francis, M. | Huang, Z. | Kool, J. | Nichol, S. | Siwabessy, J. | Wilson, O.

Abstract

This resource contains multibeam sonar bathymetry data for the continental shelf area of Flinders Commonwealth Marine Reserve, northeast Tasmania. Multibeam data were collected by Geoscience Australia and University of Tasmania in May 2011 (survey GA0331) and June-July 2012 (survey GA0337) on RV Challenger. The survey used a Kongsberg EM3002 300 kHz multibeam sonar system mounted in single head configuration to broadly classify the seabed into hard (bedrock reef), soft (sedimentary) and mixed substrate types at select locations across the shelf. The 2011 survey involved reconnaissance mapping along a series of cross-shelf transects, covering a total of 767 line km. For the 2012 survey, multibeam data (bathymetry and backscatter) were collected at 40 pre-determined stations, each covering an area approximately 200 x 200 m. The location of stations was selected using a Generalised Random Tessellation Stratified (GRTS) sampling design that ensured an even spatial distribution of sites. Multibeam data was also collected along transits between GRTS stations (410 line km) and across a 30 km2 area of the outer shelf, incorporating areas of low profile reef, sandy shelf and three shelf-incising canyon heads. Bathymetry data are gridded to 2 m spatial resolution. The 2012 survey also included seabed observations at the 40 GRTS stations using a drop camera and collection of sediment samples at 31 stations using a Shipek grab. The Flinders CMR survey was a pilot study undertaken in 2012 as part of the National Marine Biodiversity Hub's National Monitoring Evaluation and Reporting Theme. The aim of this theme is to develop a blueprint for the sustained monitoring of the South-east Commonwealth Marine Reserve Network, specifically; 1) to contribute to an inventory of demersal and epibenthic conservation values in the reserve and 2) to test methodologies and deployment strategies in order to inform future survey design efforts. Several gear types were deployed; including multibeam sonar, shallow-water (less than 150m) Baited Remote Underwater Video Systems (BRUVS), deep- water BRUVS (to 600 m), towed video and digital stereo stills. Embargo statement: Resource embargoed pending completion of NERP research. Release date 31 December 2014. Attribution statement: Data was sourced from the NERP Marine Biodiversity Hub. The Marine Biodiversity Hub is supported through funding from the Australian Government's National Environmental Research Program (NERP), administered by the Department of Sustainability, Environment, Water, Population and Communities (DSEWPAC). Dataset name: National Environmental Research Program (NERP) Marine Biodiversity Hub, 2012, Flinders Commonwealth Marine Reserve Shelf Backscatter

Product Type

dataset

eCat Id

75617

Contact for the resource

Keywords

• Marine DataBathymetry Grid

( Theme )

• bathymetry

( Theme )

• continental shelf

( Theme )

• NERP Marine Biodiversity Hub

( Theme )

• marine

( Theme )

• NERP

• AU-TAS

Australian and New Zealand Standard Research Classification (ANZSRC)

• Earth Sciences

• Published_Internal

Publication Date

2012-01-01T00:00:00

Creation Date

Security Constraints

Australian Government Security ClassificationSystem    

Classification - unclassified

Legal Constraints

Creative Commons Attribution 4.0 International Licence    

Access - license

Use - license

Status

Purpose

Maintenance Information

notPlanned

Topic Category

oceans

Series Information

Lineage

Multibeam data was processed through Caris HIPS/SIPS version 7. An existing vessel configuration file specific to RV Challenger was used with a modification to the patch test offsets. A new project was then created and the vessel configuration file was attached to the project file. The raw swath sonar data, in *.all format, for each line was then imported into the project and the vessel information assigned to the data. The motion sensor, DGPS and heading data were then cleaned using a filter that averaged adjacent data to remove artifacts. A new blank field area was defined that specified the geographic area of study and the co-ordinate system used. The co-ordinate system for all the study areas was WGS84. 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. In addition, Seafarer 2011 & 2012 with reference to UTC time was used to obtain tidal information, which in turn was used to correct for the tidal variations in the processing after first converting to the mean sea level using the in-house software GA RefTide. 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 study area. The processed data was finally exported as XYZ grid soundings and converted into ArcINFO grid at 2 m resolution and ESRI ASCII *.asc

Parent Information

Extents

[-40.85, -40.4, 148.55, 148.85]

Reference System

Spatial Resolution

Service Information

Associations

Downloads and Links

Source Information

Data was sourced from the NERP Marine Biodiversity Hub. The Marine Biodiversity Hub is supported through funding from the Australian Government's National Environmental Research Program (NERP), administered by the Department of Sustainability, Environment, Water, Population and Communities (DSEWPAC).