National Gravity Compilation 2019: Half Vertical Derivative Grid of Australia

Nearly 1.4 million gravity stations from the Australian National Gravity Database, supplemented by global marine data, were used to create this 2019 grid. Geoscience Australia processed ground observations collected from the 1940s onward, applying a half vertical derivative to de-trended global isostatic residual anomalies. The resulting image has a cell size of approximately 435 meters, revealing sub-surface geological structures across the continent and its margins.

Use Cases

• Map subsurface density variations and geological structures based on the processed gravity anomaly data.
• Identify potential mineral exploration targets based on gravity gradient features.
• Integrate with other geophysical datasets (e.g., magnetic surveys) for joint geological interpretation.
• Train machine learning models for automated geological feature detection from geophysical grids.

Strengths

• Integrates nearly 1.4 million ground gravity stations with global marine data, providing extensive coverage.
• Data quality is checked by Geoscience Australia geophysicists to ensure it is fit-for-purpose.
• Station spacing in major parts of the continent is between 2.5 and 7 km, suggesting detailed regional coverage.
• The grid is derived from observations spanning from the 1940s to 2019, offering a long historical baseline.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Station spacing varies from 11 km to less than 1 km, indicating inconsistent resolution across the continent.
• The description metadata is limited; actual data quality and specific processing parameters require manual inspection.

Provenance

Source

Geoscience Australia Data, incorporating data from Commonwealth, State, Territory Governments, industry, universities, and global sources (Scripps Institution of Oceanography, NOAA, NGA).

Collection Method

Ground and marine gravity observations processed via standard methods, with a half vertical derivative applied via Fast Fourier Transform to a de-trended global isostatic residual grid.

Time Range

Ground observations from the 1940s to September 2019.

Freshness

Last updated 2026-04-30 15:12:32.457326; freshness should be verified.

Geography

Australia and its continental margins.