Australian Gravity Anomaly Grid at 435-Meter Resolution

Gravity data measures density variations in subsurface rocks to reveal geological structure. The compilation integrates nearly 1.4 million ground stations from a national database and offshore sources, processed into a grid with a 0.00417-degree cell size. The grid was generated by Geoscience Australia and partners using data collected from the 1940s to 2019.

Use Cases

• Map subsurface density contrasts and geological structures using the half vertical derivative (0.5VD) values.
• Interpret the de-trended global isostatic residual (DGIR) anomalies to identify regions with anomalous crustal thickness.
• Correlate gravity anomaly patterns with known mineral deposits for exploration targeting.
• Analyze the spatial distribution of gravity station data, which has variable spacing from 1 km to 11 km.
• Integrate the grid with other geospatial layers using its continental margin coverage of Australia.

Strengths

• Integrates approximately 1.4 million gravity observation points from a national database.
• Provides continental coverage of Australia and its margins at a consistent 435-meter (0.00417-degree) grid resolution.
• Data underwent quality checking by GA geophysicists and uses standard processing methods.

Limitations

• Ground station density is uneven, with spacing varying from 1 km to 11 km across the continent.
• The core gravity observations are from September 2019, with older historical data included.
• Specific data formats (NetCDF, HTML) may require specialized software for analysis.

Provenance

Source

Australian National Gravity Database (ANGD) and global marine gravity grids from Scripps Institution of Oceanography, NOAA, and NGA.

Collection Method

Ground and marine gravity measurements processed via standard methods, with a fast Fourier transform (FFT) applied to calculate the half vertical derivative.

Time Range

Observations collected from the 1940s to September 2019.

Freshness

Dataset metadata was last updated in April 2026, but the underlying gravity observations are current to September 2019.

Geography

Australia and its continental margins.