2019 De-trended Isostatic Residual Gravity Map of Australia

Geoscience Australia Data provides a 2019 national gravity grid derived from 1.4 million ground gravity observations, 345,000 line km of airborne gravity, and 106,000 line km of gravity gradiometry data. The map presents a Hue-Saturation-Intensity image of De-trended Global Isostatic Residual Gravity data, with a linear color scale from -500 to +500 µm.s-2.

Use Cases

• Analyze De-trended Global Isostatic Residual Gravity (DGIR) values to identify subsurface density anomalies.
• Correlate gravity anomalies from the B Series grid with known geological features for mineral exploration targeting.
• Use the Hue-Saturation-Intensity (HSI) image representation for regional-scale geophysical interpretation and mapping.

Strengths

• Integrates a large volume of source data, including 1.4 million ground observations.
• Combines multiple survey types: 345,000 line km of airborne gravity and 106,000 line km of gravity gradiometry.
• Data collection spans a long temporal range, from the 1940s to the present day.

Limitations

• Primary deliverable is a PDF image map, limiting direct quantitative analysis of the underlying grid values.
• Specific grid resolution, cell size, and data formats for the raw grids are not detailed in the provided description.

Provenance

Source

Geoscience Australia Data, incorporating data from Commonwealth, State, Territory Governments, industry, and universities.

Collection Method

Combination of ground, airborne, and marine gravity observations, processed with isostatic correction and de-trending.

Time Range

Observations collected from the 1940s to 2019.

Freshness

Grids are based on data current as of September 2019, though the metadata record was updated in 2026.

Geography

Australia