Crustal Mass Variation in Australia from Seismic Refraction Surveys

Geoscience Australia Data provides a dataset on crustal mass deficiency (CMD) across Australia and nearby marine areas, last updated in April 2026. The data is derived from seismic refraction surveys measuring crustal velocities and layer thicknesses, with CMD values ranging from about 13 to 21 kt/m^2 on land and 15 to 17 kt/m^2 in marine regions. The variations are used to analyze departures from isostatic equilibrium at the base of the crust.

Use Cases

• Modeling regional isostatic compensation based on crustal mass deficiency (CMD) values.
• Analyzing the relationship between crustal density-depth structure and free-air gravity anomalies.
• Studying mantle density variations implied by incomplete crustal isostasy.
• Mapping geological provinces based on seismic velocity and crustal thickness averages.

Strengths

• CMD values are provided with specific ranges: about 13-21 kt/m^2 on land and 15-17 kt/m^2 in marine areas.
• Data is derived from seismic refraction surveys, a standard geophysical method.
• The dataset applies corrections for average elevation and free-air gravity to calculate CMD.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• Data freshness should be verified despite the 2026 update date.

Provenance

Source

Geoscience Australia Data

Collection Method

Calculated from averages of seismic refraction survey data on crustal velocities and layer thicknesses.

Freshness

Last updated 2026-04-20 02:50:31.622326

Geography

Australia and nearby marine areas