Authors / CoAuthors
Unknown
Abstract
These colour and greyscale images are digital pictorial representations of a grid of onshore Bouguer Anomaly station values (Bouguer density of 2.67 t/m3) and offshore free air pseudo gravity station values extracted from the World Gravity Image (Sandwell and Smith, 1995). The onshore gravity observations are held in the Australian National Gravity Database (1997). These images contain wavelengths as small as 30 000 m. Gravity digital data are available in point located form or as a grid for the Australian continent as a whole or for smaller areas.
Product Type
dataset
eCat Id
77086
Contact for the resource
Custodian
Point of contact
Cnr Jerrabomberra Ave and Hindmarsh Dr GPO Box 378
Canberra
ACT
2601
Australia
Keywords
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- GIS Dataset
- Australian and New Zealand Standard Research Classification (ANZSRC)
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- Earth Sciences
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- Published_Internal
Publication Date
2013-08-20T00:00:00
Creation Date
Security Constraints
Legal Constraints
Status
Purpose
Maintenance Information
continual
Topic Category
geoscientificInformation
Series Information
Lineage
These images are of a grid of Bouguer gravity anomalies onshore, and free air gravity anomalies offshore. The onshore data arise from a compilation of data from about 700000 land gravity stations which were collected on a regional grid of stations spaced between 7 km and 11 km and supplemented by infill surveys and profiles. All these data are held in the Australian National Gravity Database. The offshore gravity anomalies have been extracted from the World Gravity Image dataset (Sandwell and Smith, 1995, 1997), treated as pseudo gravity stations. The onshore and offshore datasets were combined and gridded together as a homogeneous dataset to create a grid with cell size 1.5 minutes of arc (approximately 2 500m). The grid was reprojected to lambert conformal conic projection, with a cellsize of 2500 metres. The grids were histogram equalised prior to imaging. These data were then low-pass filtered in the frequence domain to remove wavelengths less than 30 000m. The colour image uses the pseudocolor palette, and the grid has been manipulated to simulate an "illumination" from the northwest. Sandwell, D T, and Smith, W H F, 1995 - marine gravity from satellite altimetry (poster). The Geological Data Centre, Scripps Institute of Oceanography, La Jolla CA 92093 (digital file version 7.2) annonymous ftp to baltica.ucsd.edu. Sandwell, D. T. & Smith, W H F, 1997 - Marine gravity anomaly from Geosat and ERS - 1. Journal of Geophysical research.
Parent Information
Extents
[-48.0, -7.0, 103.0, 168.0]
Reference System
Spatial Resolution
Service Information
Associations
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Source Information
Unknown