National Gravity Compilation 2019: First 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. Geoscience Australia processed ground and marine observations collected from the 1940s onward to produce a first vertical derivative image of de-trended global isostatic residual anomalies. The resulting grid has a cell size of approximately 435 meters and covers Australia and its continental margins.

Use Cases

• Modeling subsurface density variations based on the first vertical derivative of gravity anomalies.
• Interpreting geological structures for mineral exploration based on the processed gravity grid.
• Integrating gravity data with other geophysical surveys for regional geological studies.
• Assessing continental margin geology using the combined onshore and offshore gravity data.

Strengths

• Derived from nearly 1.4 million gravity stations, providing dense continental coverage.
• Integrates decades of data collected from the 1940s to 2019 by government, industry, and research bodies.
• Processed and quality-checked by Geoscience Australia geophysicists to be fit-for-purpose.
• Combines onshore data from the Australian National Gravity Database with offshore data from global institutions like Scripps and NOAA.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Station spacing for ground observations varies from 11 km to less than 1 km, indicating uneven data density.
• Freshness should be verified; the underlying data is from September 2019, though the record was updated in 2026.

Provenance

Source

Geoscience Australia (implied), Australian National Gravity Database, and global gravity grids from Scripps Institution of Oceanography, NOAA, and NGA.

Collection Method

Ground and marine gravity observations processed via standard methods, with a fast Fourier transform applied to calculate the first vertical derivative.

Time Range

1940s to September 2019.

Freshness

Last updated 2026-06-04 06:36:05.792629; underlying data is from September 2019.

Geography

Australia and its continental margins.