National Gravity Compilation 2019: First Vertical Derivative Grid of Australia

A 2019 compilation grid derived from nearly 1.4 million gravity stations in the Australian National Gravity Database and offshore data. The grid has a cell size of 0.00417 degrees (approximately 435m) and shows the first vertical derivative of de-trended global isostatic residual anomalies over Australia and its continental margins. The data, processed and quality-checked by Geoscience Australia (GA) geophysicists, incorporates ground observations collected by various entities from the 1940s to 2019.

Use Cases

• Interpret subsurface geological structure based on gravity anomaly patterns.
• Model crustal thickness and density variations using the first vertical derivative of isostatic residuals.
• Integrate gravity data with other geophysical datasets for regional exploration studies.
• Analyze long-term changes in gravity data collection coverage and station density across Australia.

Strengths

• Derived from a substantial base of nearly 1.4 million gravity stations from the Australian National Gravity Database.
• Processed using standard methods and checked for quality by GA geophysicists to be fit-for-purpose.
• Incorporates data from a long temporal range, with ground observations from the 1940s to 2019.
• Provides continental-scale coverage over Australia and its margins with a defined grid cell size of ~435m.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment for specific computational tasks.
• Station spacing for the underlying ground observations varies from 11 km to less than 1 km, indicating non-uniform data density.

Provenance

Source

Geoscience Australia (GA), Australian Ocean Data Network.

Collection Method

Grid produced from the 2019 Australian National Gravity Grids A series, applying a fast Fourier transform (FFT) process to the DGIR grid.

Time Range

Ground observations from 1940s to 2019, compiled as of September 2019.

Freshness

Last updated 2026-04-10 22:24:05.205699; freshness should be verified.

Geography

Australia and its continental margins.