National Gravity Compilation 2019: Free Air Anomaly Grid for Australia

A 2019 compilation integrates approximately 1.8 million gravity observations from the 1940s to the present day. Geoscience Australia produced this free air anomaly grid using ground data, offshore global grids, and airborne surveys totaling 345,000 line km of gravity and 106,000 line km of gravity gradiometry data. The resulting grid has a cell size of approximately 435 meters, covering Australia and its continental margins.

Use Cases

• Modeling subsurface density variations based on free air gravity anomaly measurements.
• Mapping geological structures and basin architecture for mineral exploration.
• Integrating airborne and ground gravity data to improve resolution in areas with sparse ground coverage.
• Conducting regional geophysical studies of the Australian continent and its margins.

Strengths

• Integrates a large volume of data, including nearly 1.4 million ground stations and extensive airborne surveys.
• Combines multiple data sources (ground, airborne, offshore) to improve continental coverage and resolution.
• Data has been processed via standard methods and quality-checked by GA geophysicists to be fit-for-purpose.
• Provides fine spatial resolution with a grid cell size of approximately 435 meters and variable station spacing.

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.

Provenance

Source

Geoscience Australia Data, incorporating data from Commonwealth, State/Territory Governments, industry, universities, and global sources.

Collection Method

Processed from ground observations in the Australian National Gravity Database, supplemented with offshore global gravity data and airborne surveys.

Time Range

Data acquired from the 1940s to present, compiled as of September 2019.

Freshness

Last updated 2026-04-20 01:16:16.146148; freshness should be verified.

Geography

Australia and its continental margins.