National Gravity Compilation 2019: Half-Derivative Bouguer Anomaly Grid for Australia

Australia and its continental margins are covered by this gravity anomaly grid with a cell size of approximately 435 meters. The grid is derived from nearly 1.4 million ground stations and over 450,000 line kilometers of airborne surveys, processed by Geoscience Australia. It represents the half vertical derivative of the complete spherical cap Bouguer anomaly, calculated via a fast Fourier transform.

Use Cases

• Map subsurface geological structures based on gravity anomaly data.
• Support mineral and resource exploration by identifying density contrasts in the crust.
• Integrate with other geophysical datasets for regional geological interpretation.
• Calculate terrain corrections for gravity surveys using the described bathymetry and topography data.

Strengths

• Integrates approximately 1.8 million gravity observations from ground and airborne sources.
• Cell size of 0.00417 degrees (approximately 435m) provides a defined 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.
• Row count is unknown, which may limit suitability assessment.

Provenance

Source

Geoscience Australia Data

Collection Method

Derived from the 2019 Australian National Gravity Grids A series, combining the Australian National Gravity Database and global offshore data from Scripps Institution of Oceanography, NOAA, and NGA.

Time Range

Ground data collected from the 1940s to September 2019.

Freshness

Last updated 2026-03-25 16:52:10.797305; freshness should be verified.

Geography

Australia and its continental margins.