National Gravity Compilation 2019: Airborne DGIR Tilt Grid for Australia

A gravity anomaly grid for Australia and its continental margins, derived from approximately 1.8 million ground and airborne observations. The grid, with a cell size of 0.00417 degrees (~435m), was generated by Geoscience Australia using data from the 1940s to 2019, including nearly 1.4 million ground stations and 451,000 line km of airborne surveys. It applies a tilt filter to the de-trended global isostatic residual (DGIR) to highlight edges of geological units.

Use Cases

• Map geological structure edges based on the applied tilt filter described.
• Model subsurface density variations based on gravity anomaly data.
• Integrate with other geophysical data for mineral exploration based on the high-resolution airborne surveys mentioned.
• Study isostatic compensation and crustal thickness based on the de-trended global isostatic residual (DGIR) process.

Strengths

• Integrates approximately 1.8 million observations from ground, airborne gravity, and gravity gradiometry surveys.
• Includes data acquired from the 1940s to present day, providing historical depth.
• Uses airborne data (451,000 line km total) to improve resolution in areas with lower-quality ground data.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.

Provenance

Source

Geoscience Australia Data, supplemented by offshore data from Scripps Institution of Oceanography, NOAA, and NGA.

Collection Method

Processed from the Australian National Gravity Database and airborne surveys, with a tilt filter applied via Fast Fourier Transform.

Time Range

1940s to 2019 (data acquisition), compiled as of September 2019.

Freshness

Last updated 2026-03-25 16:34:51.096012; freshness should be verified.

Geography

Australia and its continental margins.