Australian compilation of seismic-derived bathymetry.

Area of Science:

• Geophysics
• Marine Geology
• Oceanography

Background:

• Bathymetric data is crucial for understanding seafloor topography and geological processes.
• Existing bathymetric datasets often have limitations in resolution and coverage.
• Seismic reflection data offers a potential high-resolution alternative for bathymetry.

Purpose of the Study:

• To create a comprehensive national seismic-derived bathymetric compilation.
• To assess the accuracy and applicability of seismic data for bathymetric mapping.
• To provide a high-resolution dataset for marine geological and geophysical studies.

Main Methods:

• Integration of 253 3D seismic surveys into four regional compilations.
• Utilizing seismic survey first returns and echosounder measurements.
• Data processing involved time-to-depth conversion, filtering, and datum reduction to WGS84 and EGM2008.

Main Results:

• A national bathymetric dataset covering 267,000 km² with 30x30m resolution and 5m+5%d vertical accuracy.
• Demonstrated that seismic first returns accurately capture the substratum topography under thin sediment layers.
• Validated seismic-derived bathymetry against multibeam echosounder surveys.

Conclusions:

• Seismic-derived bathymetry provides a valuable, high-resolution dataset for national-scale mapping.
• This method is effective for delineating seafloor geomorphology, particularly over hard substrates.
• The compiled dataset enhances capabilities for marine resource management and geological research.