National Gravity Compilation 2019 DGIR Tilt Grid: Australia and Continental Margins

1.8 million gravity observations, including nearly 1.4 million ground stations, were processed to create this grid. The DGIR tilt grid shows de-trended global isostatic residual anomalies over Australia and its continental margins at a 435-meter resolution. Ground data from the 1940s onward, sourced from government, industry, and research bodies, were combined with global marine data to produce this geological structure analysis tool.

Use Cases

• Detecting edges of geological units based on the tilt filter ratio of vertical to horizontal derivatives.
• Mapping subsurface density variations for mineral exploration based on gravity anomaly data.
• Studying continental margin structure using combined terrestrial and marine gravity observations.
• Analyzing long-term geological changes using data collected from the 1940s to 2019.

Strengths

• Grid cell size of 0.00417 degrees (approximately 435m) provides high spatial resolution.
• Data quality was checked by GA geophysicists to ensure fitness for purpose.
• Incorporates nearly 1.4 million ground stations from the Australian National Gravity Database.
• Combines terrestrial data with offshore data from a global gravity grid (v28.1).

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Station spacing for ground observations varies from 11 km to less than 1 km, indicating uneven coverage.
• Data freshness should be verified; the underlying observations are from September 2019.

Provenance

Source

Australian Ocean Data Network, incorporating data from Commonwealth, State, Territory Governments, industry, universities, and global institutions.

Collection Method

Ground observations processed via standard methods and combined with offshore data from Scripps Institution of Oceanography, NOAA, and NGA.

Time Range

1940s to September 2019

Freshness

Last updated 2026-05-05 01:35:54.035444

Geography

Australia and its continental margins