Australian Free Air Gravity Anomaly Grid at 435m Resolution, 2019

A 2019 compilation of approximately 1.4 million ground gravity stations from the Australian National Gravity Database, supplemented with offshore data. The grid shows free air anomalies over Australia and its continental margins with a cell size of 0.00417 degrees (approximately 435m). Data was acquired by government, industry, and research organizations from the 1940s onward and processed by Geoscience Australia.

Use Cases

• Modeling subsurface geological structures based on free air gravity anomalies.
• Mapping continental margins and crustal thickness based on gravity data.
• Integrating with magnetic or seismic data for mineral and petroleum exploration.
• Studying long-term changes in Earth's gravity field based on data collected since the 1940s.

Strengths

• Derived from nearly 1.4 million quality-checked gravity stations out of approximately 1.8 million in the national database.
• Station spacing varies from 11 km to less than 1 km, with major parts of the continent between 2.5 and 7 km.
• Incorporates offshore data from a global gravity grid developed by Scripps Institution of Oceanography, NOAA, and NGA.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Data freshness should be verified; the grid is a 2019 compilation of historical data.

Provenance

Source

Geoscience Australia Data, supplemented with data from Scripps Institution of Oceanography, NOAA, and NGA.

Collection Method

Ground observations processed via standard methods and checked by GA geophysicists, gridded with offshore data.

Time Range

1940s to 2019 (compilation date).

Freshness

Last updated 2026-04-20 03:02:13.080271; grid compilation date is 2019.

Geography

Australia and its continental margins.