National Gravity Compilation 2019 DGIR: Subsurface Density Anomalies Over Australia

A gravity anomaly image grid covering Australia and its continental margins, derived from approximately 1.8 million gravity observations. The grid has a cell size of 0.00417 degrees (approximately 435 meters) and is expressed in gravity units (um/s^2). It was produced by Geoscience Australia from ground and marine data compiled up to September 2019, incorporating measurements collected from the 1940s onward.

Use Cases

• Model subsurface geological structures based on de-trended global isostatic residual anomalies.
• Analyze continental-scale density variations based on gravity anomaly data.
• Integrate gravity data with other geophysical surveys for resource exploration.
• Study long-term changes in gravity data collected from the 1940s to 2019.

Strengths

• Derived from nearly 1.4 million gravity stations from the Australian National Gravity Database.
• Incorporates offshore data from a global gravity grid developed by Scripps Institution of Oceanography, NOAA, and NGA.
• Data quality was checked by GA geophysicists to ensure it is fit-for-purpose.
• Ground station spacing varies from 11 km down to less than 1 km, with major parts of the continent between 2.5 and 7 km.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.

Provenance

Source

Geoscience Australia (GA), Australian Ocean Data Network.

Collection Method

Processed from ground observations in the Australian National Gravity Database and supplemented by global marine gravity data.

Time Range

Data acquired from the 1940s to September 2019.

Freshness

Last updated 2026-04-10 21:43:50.630006; freshness should be verified.

Geography

Australia and its continental margins.