Bathymetry Grid of South Tasman Rise Region (2003) [DERIVED]  

Authors / CoAuthors

Abstract

A bathymetric grid of the South Tasman Rise Region (Longitudes 138° E - 158° E, Latitudes 38° S - 54° S) is produced. In doing so, the individual datasets used have been closely examined and any deficiencies noted for further follow up or have been rectified immediately and the changes documented. These datasets include modern multibeam data, coastline data obtained from georeferenced SPOT imagery, hydrographic quality data, echosounder data from research vessels and satellite derived bathymetric data. A hierarchical system was employed whereby the best and most extensive datasets were gridded first and applied as a mask to the next best dataset. A new masking grid would be formed from these datasets to pass non-overlapping data in the next best dataset. This procedure was employed until finally the satellite data were masked. All the various levels of masked data were then brought together by the gridding algorithm (Intrepid - Desmond Fitzgerald Associates) and an ERMapper format grid produced. A grid cell size of 0.00225° (nominal 250m) was used with many iterations of minimum curvature gridding and several passes of smoothing. The final grid is available in ERMapper, ArcInfo and ASCII xyz formats

Product Type

nonGeographicDataset

eCat Id

67180

Contact for the resource

Keywords

• Marine MapBathymetry Map

( Theme )

• marine

Australian and New Zealand Standard Research Classification (ANZSRC)

• Marine Geoscience

• Published_Internal

Publication Date

2008-07-14T00:00:00

Creation Date

Security Constraints

Australian Government Security ClassificationSystem    

Classification - unclassified

Legal Constraints

Creative Commons Attribution 4.0 International Licence    

Access - restricted

Use - license

Status

Purpose

Maintenance Information

asNeeded

Topic Category

geoscientificInformation

Series Information

Lineage

The grid is derived from data in Geoscience Australia databases and recent sources which will eventually be entered into those databases. Nineteen swath datasets acquired between 1994 and 2003 were used. Six of the surveys supply extensive areal coverage, whilst the others are basically multibeam transits of the area. Detailed hydrographic data exists in the area of Bass Strait and around the Australian and Tasmanian coastlines. A high quality coastline of Australia and its islands was obtained from the National Mapping Division of G.A. Seventy-seven surveys from the G.A. MARDAT database. These data range in vintage from 1961 to 2002 and were edited to remove suspect datapoints, but were left uncorrected with regards speed of sound issues. All available data in the area from the AAD voyages in the region. Extensive editing and a weighting scheme were employed to discriminate between closely spaced data of varying vintages. Satellite derived bathymetry from the SIO website was used to infill areas that had no higher quality observations within a nominal 10 kilometres.

Parent Information

Extents

[-54.0, -38.0, 138.0, 158.0]

Reference System

Spatial Resolution

Service Information

Associations

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Source Information

Source data not available.