National Gravity Compilation 2019: Airborne DGIR Image of Australia

Geoscience Australia's 2019 National Gravity Compilation includes a de-trended global isostatic residual (DGIR) image derived from gravity data. The grid is based on nearly 1.4 million ground stations and over 450,000 line kilometers of airborne gravity and gradiometry surveys collected from the 1940s to 2019. It covers Australia and its continental margins with a cell size of approximately 435 meters, with data provided in gravity units (um/s^2).

Use Cases

• Modeling subsurface geological structures based on gravity anomaly data.
• Enhancing mineral exploration targeting by interpreting density variations in the crust.
• Integrating airborne and ground gravity data to improve resolution in areas with sparse ground coverage.
• Conducting geophysical research on isostatic compensation and crustal thickness over Australia.

Strengths

• Integrates a large volume of observations, including nearly 1.4 million ground stations and over 450,000 line km of airborne data.
• Provides continent-wide coverage of Australia and its margins with a consistent grid resolution of approximately 435 meters.
• Combines multi-source data from government, industry, and research organizations collected over several decades, up to September 2019.
• Data underwent quality checking by Geoscience Australia geophysicists to ensure it is fit-for-purpose.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• The specific file format (NetCDF) may require specialized geospatial libraries for analysis.
• Ground station spacing varies from 11 km to less than 1 km, which may lead to uneven resolution in some regions.

Provenance

Source

Geoscience Australia Data, incorporating data from Commonwealth, State, Territory Governments, mining industry, universities, and global sources like Scripps Institution of Oceanography.

Collection Method

Processed from ground observations in the Australian National Gravity Database, offshore global gravity grids, and airborne gravity/gradiometry surveys.

Time Range

1940s to 2019 (with database snapshot as of September 2019).

Freshness

Last updated 2026-04-30 15:21:40.965941; freshness should be verified.

Geography

Australia and its continental margins.