National Gravity Compilation 2019 DGIR Grid: Subsurface Density Anomalies Over 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. The grid shows de-trended global isostatic residual anomalies with a cell size of approximately 435 meters, derived from ground observations collected from the 1940s onward. It was processed and quality-checked by Geoscience Australia geophysicists to reveal the geological structure beneath the Earth's surface.

Use Cases

• Model subsurface geological structures based on gravity anomaly data.
• Identify potential mineral exploration targets based on density variations in the crust.
• Integrate with other geophysical datasets for continental-scale geological interpretation.
• Study isostatic compensation and crustal thickness variations across Australia and its margins.

Strengths

• Derived from nearly 1.4 million gravity stations, providing dense spatial coverage.
• Grid cell size of 0.00417 degrees (approximately 435m) offers regional detail.
• Data quality was checked by GA geophysicists to ensure it is fit-for-purpose.
• Incorporates decades of observations from government, industry, and research sources since the 1940s.

Limitations

• Station spacing for ground observations is variable, ranging from 11 km to less than 1 km.
• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment for some computational tasks.

Provenance

Source

Australian Ocean Data Network, aggregating data from Geoscience Australia, Commonwealth/State/Territory Governments, industry, and universities.

Collection Method

Grid generated from ground observations in the Australian National Gravity Database and offshore data from the Scripps Institution of Oceanography Global Gravity grid.

Time Range

Observations from the 1940s to September 2019.

Freshness

Last updated 2026-04-16 08:53:08.620348; freshness should be verified.

Geography

Australia and its continental margins.