National Gravity Compilation 2019: Free Air Anomaly Grid for Australia

Nearly 1.4 million gravity stations from the Australian National Gravity Database were used to generate this free air anomaly grid. The data, collected from the 1940s onward by government, industry, and research bodies, reveals geological structures beneath the Earth's surface. This 2019 compilation has a cell size of approximately 435 meters and covers Australia and its continental margins.

Use Cases

• Model subsurface geological structures based on gravity anomaly data.
• Support mineral and hydrocarbon exploration based on density variations in the sub-surface.
• Integrate with other geophysical datasets for regional geological studies based on the continental-scale grid.
• Calibrate or validate satellite-derived gravity models based on ground and offshore observations.

Strengths

• Derived from nearly 1.4 million gravity stations out of approximately 1.8 million total observations.
• Station spacing varies from 11 km down to less than 1 km, with major parts of the continent between 2.5 and 7 km.
• Grid cell size is 0.00417 degrees (approximately 435m), providing detailed spatial resolution.
• Data quality was checked by GA geophysicists to ensure it is fit-for-purpose.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Last updated 2026-06-23 01:35:23.262346; freshness should be verified.
• Data may reflect geographic and temporal bias inherent to data_gov_au, with collection spanning from the 1940s to present.

Provenance

Source

Australian Ocean Data Network, incorporating data from Commonwealth, State, Territory Governments, mining industry, universities, and research organisations.

Collection Method

Ground observations processed via standard methods, supplemented with offshore data from Scripps Institution of Oceanography, NOAA, and NGA.

Time Range

1940s to 2019

Freshness

Last updated 2026-06-23 01:35:23.262346.

Geography

Australia and its continental margins