National Gravity Compilation 2019: Half-Vertical Derivative Grid of Australia

Nearly 1.4 million gravity stations from the Australian National Gravity Database, supplemented by offshore data, were used to generate this 2019 grid. The grid has a cell size of approximately 435 meters and shows the half vertical derivative of de-trended global isostatic residual anomalies over Australia and its continental margins. The data, processed and quality-checked by Geoscience Australia, were acquired from the 1940s onward by government, industry, and research organizations.

Use Cases

• Map subsurface geological structures based on gravity anomaly data.
• Model crustal density variations for resource exploration based on the processed gravity grid.
• Integrate gravity data with other geophysical surveys for regional geological interpretation.
• Study isostatic compensation and tectonic features over the Australian continent based on the de-trended residual anomalies.

Strengths

• Derived from nearly 1.4 million gravity stations, providing dense spatial coverage.
• Ground station spacing varies from 11 km down to less than 1 km, with major parts of the continent between 2.5 and 7 km.
• Incorporates data from the 1940s to 2019, offering a long historical record.
• Quality-checked by Geoscience Australia geophysicists to be fit-for-purpose.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• The specific file size and exact row/column counts for the grid are unknown.
• Data may reflect geographic and temporal bias inherent to the aggregation of surveys over decades.

Provenance

Source

Geoscience Australia Data, incorporating the Australian National Gravity Database and global data from Scripps Institution of Oceanography, NOAA, and NGA.

Collection Method

Ground and marine gravity observations processed via standard methods, with the final grid produced by applying a fast Fourier transform to a de-trended global isostatic residual grid.

Time Range

1940s to 2019 (ground data), with the compilation dated to September 2019.

Freshness

Last updated 2026-04-20 03:21:36.716756; freshness should be verified.

Geography

Australia and its continental margins.