National Gravity Compilation 2019: First Vertical Derivative Grid of Australia

Australia and its continental margins are covered by a gravity anomaly grid with a cell size of approximately 435 meters. The grid is derived from nearly 1.4 million ground and marine gravity observations stored in the Australian National Gravity Database as of September 2019, with ground data collected from the 1940s onward. It shows the first vertical derivative of de-trended global isostatic residual anomalies, processed by Geoscience Australia.

Use Cases

• Map subsurface geological structures based on gravity anomaly variations.
• Support mineral and resource exploration by identifying density contrasts in the crust.
• Model isostatic compensation and crustal thickness based on processed residual anomalies.
• Integrate with other geophysical data for regional geological interpretation.

Strengths

• Derived from nearly 1.4 million gravity stations, providing dense spatial coverage.
• Ground data collection spans from the 1940s to the present, offering a long historical record.
• Station spacing in major parts of the continent is between 2.5 and 7 kilometers, indicating detailed sampling.
• Processed and quality-checked by GA geophysicists to be fit-for-purpose.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment for specific analytical methods.
• Data may reflect geographic and temporal bias inherent to the aggregation of multi-source observations over decades.

Provenance

Source

Geoscience Australia (GA), Australian National Gravity Database, supplemented by Scripps Institution of Oceanography/NOAA/NGA global grid.

Collection Method

Ground and marine gravity observations processed via standard methods, including isostatic correction and Fast Fourier Transform.

Time Range

Ground data from 1940s to 2019; grid represents compilation as of September 2019.

Freshness

Last updated 2026-06-23 06:05:00.037388; freshness should be verified.

Geography

Australia and its continental margins.