National Gravity Compilation 2019: First Vertical Derivative Image of Australia

Approximately 1.8 million gravity observations, including nearly 1.4 million ground stations, were used to create this grid. The Australian Ocean Data Network produced this image from the 2019 Australian National Gravity Grids A series, incorporating data from the 1940s to present day. It represents the first vertical derivative of de-trended global isostatic residual anomalies over Australia and its continental margins at a cell size of approximately 435 meters.

Use Cases

• Map subsurface geological structures based on gravity anomaly patterns.
• Identify density variations in the Earth's crust for mineral exploration.
• Integrate gravity data with other geospatial datasets for regional geological modeling.
• Train models to detect geophysical anomalies based on processed derivative grids.

Strengths

• Incorporates approximately 1.8 million gravity observations from multiple sources.
• Data quality is checked by GA geophysicists to ensure fitness for purpose.
• Grid has a defined cell size of 0.00417 degrees (approximately 435m).
• Combines ground data from 1940s to present with offshore global gravity data.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• Data may reflect geographic bias inherent to the uneven station spacing (11 km to less than 1 km).

Provenance

Source

Australian Ocean Data Network, utilizing the Australian National Gravity Database and global gravity grids.

Collection Method

Ground and marine gravity observations processed via standard methods and a Fast Fourier Transform (FFT).

Time Range

1940s to present day (with database snapshot as of September 2019).

Freshness

Last updated 2026-05-05 02:10:14.534343; freshness should be verified.

Geography

Australia and its continental margins.