The Creation of High Resolution Bathymetry Grids for the Lord Howe Island Region
Dataset Identification:
Resource Abstract:
Detailed seabed bathymetric data are needed to better understand our marine environment because models of seabed morphology
derived from these data provide useful insights into physical processes that act on the seabed and the location of different
types of seabed habitats. Lord Howe Island lies approximately 450km off the northern coast of New South Wales. It is a volcanic
island with a fringing coral reef on its western shore, and a shallow (20 - 120 m) shelf surrounds the island. Bathymetry
data are required in this area to help identify major seabed processes and habitats, especially relict reef structures, and
to measure how well physical seabed properties act as surrogates of patterns of biodiversity on this mid-ocean carbonate shelf.
The data are also required to enable modelling of tsunami as they interact with the shelf around the island and the coast.
This report describes the methodology employed in creating detailed bathymetry data grids of the Lord Howe Island region.
It covers data collection, quality control and gridding. Descriptions are provided of each dataset employed, the methods used
to integrate the different datasets and the attributes of the new bathymetry models.Four new bathymetry grids are presented,
including grids that integrate bathymetry with the island's topography.
Citation
Title The Creation of High Resolution Bathymetry Grids for the Lord Howe Island Region
The grids are derived from data in Geoscience Australia databases and recent sources which will eventually be entered into
those databases. Satellite derived bathymetry was used in shallow waters. Seven swath datasets acquired between 1992 and 2009
were used. Five of the surveys supply extensive regional coverage, whilst the others are basically multibeam transits of the
area. One LADS survey from the AHS was used. A high quality coastline, as well as topography data of Lord Howe and its islands
were obtained from the Land and Property Information Management Authority. Eleven singlebeam surveys from the GA MARDAT database.
These data range in vintage from 1971 to 1998 and were edited to remove suspect datapoints, but were left uncorrected with
regards speed of sound issues. Chart data from the AHS was used in both deep and shallow water but most of it was superseded
by swath data. ETOPO1 data was used in the area of two seamounts where data were sparse. One singlebeam survey fro the University
of Wollongong that was previously unknown to GA was used.
Metadata hierarchy level name:
dataset - GA Publication - Record
Metadata language
eng
Metadata character set encoding:
utf8
Metadata standard for this record:
ANZLIC Metadata Profile: An Australian/New Zealand Profile of AS/NZS ISO 19115:2005, Geographic information - Metadata
standard version:
1.1
Metadata record identifier:
a05f7892-f857-7506-e044-00144fdd4fa6
URI for dataset described:
> http://www.ga.gov.au/metadata-gateway/metadata/record/70649/
Metadata record format is ISO19139-2 XML (MI_Metadata)