National Gravity Compilation 2019: First Vertical Derivative Grid of Australia

A geospatial grid showing the first vertical derivative of de-trended global isostatic residual gravity anomalies across Australia and its continental margins. The grid is derived from nearly 1.4 million gravity stations from the Australian National Gravity Database and offshore sources, with a cell size of approximately 435 meters. Geoscience Australia produced this compilation, incorporating ground observations collected from the 1940s to September 2019.

Use Cases

• Map subsurface density variations based on the first vertical derivative of gravity anomalies.
• Model geological structures for mineral exploration using processed isostatic residual data.
• Integrate gravity data with other geophysical surveys for continental-scale geological interpretation.

Strengths

• Derived from nearly 1.4 million gravity stations, providing dense continental coverage.
• Grid cell size of 0.00417 degrees (approximately 435m) offers a detailed spatial resolution.
• Data quality was checked by GA geophysicists to ensure it is fit-for-purpose.
• Incorporates ground observations spanning from the 1940s to 2019, providing historical depth.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Station spacing for ground observations varies from 11 km to less than 1 km, indicating uneven data density.

Provenance

Source

Geoscience Australia Data, supplemented by Scripps Institution of Oceanography, NOAA, and NGA.

Collection Method

Processed from ground observations in the Australian National Gravity Database and offshore global gravity data via Fast Fourier Transform (FFT).

Time Range

Ground observations from the 1940s to September 2019.

Freshness

Last updated 2026-03-25 17:21:29.234999; freshness should be verified.

Geography

Australia and its continental margins.