National Gravity Compilation 2019: DGIR 1VD Image of Australia

Geoscience Australia's National Gravity Compilation 2019 includes a first vertical derivative image of de-trended global isostatic residual (DGIR) anomalies. The grid is derived from approximately 1.8 million gravity observations, including nearly 1.4 million ground stations and 451,000 line km of airborne surveys, with a cell size of about 435m. Data sources include the Australian National Gravity Database, global gravity grids, and surveys conducted from the 1940s to 2019.

Use Cases

• Modeling subsurface geological structures based on gravity anomaly data.
• Enhancing mineral exploration targeting based on high-resolution airborne gravity and gradiometry data.
• Conducting continental-scale geophysical research based on the integrated national gravity grid.
• Calibrating or validating regional geophysical models based on the processed DGIR anomalies.

Strengths

• Integrates a large volume of observations, including nearly 1.4 million ground stations and 451,000 line km of airborne data.
• Combines multiple data sources (ground, offshore global grids, airborne) for comprehensive continental coverage.
• Processed with standard methods and quality-checked by GA geophysicists to be fit-for-purpose.
• Provides high-resolution data with ground station spacing as low as 1 km and airborne line spacing as low as 0.5 km.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• Data may reflect geographic or source bias inherent to the aggregation of historical surveys.

Provenance

Source

Geoscience Australia (GA), via the Australian Ocean Data Network.

Collection Method

Processed from the 2019 Australian National Gravity Grids B series, derived from ground observations, global offshore grids, and airborne surveys.

Time Range

Surveys conducted from the 1940s to 2019, with database snapshot as of September 2019.

Freshness

Last updated 2026-04-28 15:22:35.107014; freshness should be verified.

Geography

Australia and its continental margins.