National Gravity Compilation 2019: Airborne DGIR Grid for Australia

Approximately 1.8 million gravity observations, including nearly 1.4 million ground stations and 451,000 line km of airborne surveys, were used to generate this grid. The data, compiled by Geoscience Australia, measures subsurface rock density variations and includes observations from the 1940s to 2019. It provides a de-trended global isostatic residual anomaly grid at a 0.00417-degree cell resolution.

Use Cases

• Model subsurface geological structures based on gravity anomaly measurements.
• Enhance mineral exploration targeting based on density contrasts revealed by the gravity grid.
• Integrate with magnetic or seismic data for regional geological interpretation based on the multi-source compilation.
• Calibrate airborne gravity survey methods based on the included 345,000 line km of airborne gravity data.

Strengths

• Integrates approximately 1.8 million observations from multiple sources (ground, airborne, offshore).
• Data quality was checked by GA geophysicists to ensure it is fit-for-purpose.
• Grid cell size of 0.00417 degrees (approximately 435m) provides regional-scale resolution.
• Includes modern airborne gravity and gradiometry data to improve resolution in areas with poor ground data.

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 spatial density.

Provenance

Source

Geoscience Australia, incorporating data from Commonwealth, State, Territory Governments, industry, and universities.

Collection Method

Processed from the Australian National Gravity Database and global gravity grids, with airborne data supplementation.

Time Range

Observations from the 1940s to September 2019.

Freshness

Last updated 2026-03-25 16:53:14.422875; freshness should be verified.

Geography

Australia and its continental margins.