National Gravity Compilation 2019: DGIR Tilt Image of Australia

A geospatial grid of de-trended global isostatic residual (DGIR) tilt anomalies over Australia and its continental margins, derived from approximately 1.4 million gravity stations. The data were compiled from the 2019 Australian National Gravity Grids A series, integrating ground observations from the 1940s onward and offshore data from global sources. The grid has a cell size of 0.00417 degrees (approximately 435 meters) and was processed using a fast Fourier transform (FFT) to calculate the tilt filter.

Use Cases

• Detect edges of geological units based on the tilt filter derived from gravity anomalies.
• Map subsurface density variations and geological structure across the Australian continent.
• Integrate gravity data with other geophysical datasets for regional geological interpretation.

Strengths

• Derived from nearly 1.4 million gravity stations, providing dense spatial coverage.
• Grid cell size of approximately 435 meters offers a relatively high resolution for continental-scale analysis.
• Data quality was checked by GA (Geoscience Australia) geophysicists to ensure it is fit-for-purpose.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Ground station spacing varies from 11 km to less than 1 km, leading to inconsistent data density in some areas.

Provenance

Source

Australian Ocean Data Network, incorporating data from Geoscience Australia's National Gravity Database and global marine data.

Collection Method

Processed from ground and marine gravity observations using standard geophysical methods and a fast Fourier transform (FFT).

Time Range

Ground data collected from the 1940s to September 2019.

Freshness

Last updated 2026-04-16 10:02:34.041899; freshness should be verified.

Geography

Australia and its continental margins.