Slow Seafloor Spreading Patterns Off Southern Australia 96-44.5 Ma

A compilation of seafloor spreading magnetic data confirms the pattern of slow spreading (half-rate <4.4 mm/year) from breakup at 96 Ma to A20 time at 44.5 Ma off Australia's southern margin. The dataset includes critical data from the 1986 R/V Rig Seismic cruise and characterizes spreading ridge jumps between 131.25°E and Tasmania and variable spreading isochron azimuths.

Use Cases

• Analyze the relationship between separation azimuth (335°) and variable spreading isochron azimuths (e.g., 090°±5°, 075°-080°) to model oblique spreading systems.
• Model the response of a slow spreading system (<4.4 mm/year half-rate) to confinement using data on ridge jumps between 131.25°E and Tasmania.
• Compare the variable azimuth of spreading isochrons in this dataset to patterns in the Gulf of Aden for studies of slow, confined spreading.

Strengths

• Includes critical magnetic data from a dedicated 1986 research cruise (R/V Rig Seismic).
• Covers a defined, significant geological time range from 96 Ma (breakup) to 44.5 Ma (A20 time).
• Compiles data for the entire southern margin of Australia, providing a regional-scale view.

Limitations

• Primary data format is PDF/HTML, requiring extraction for computational analysis.
• Sample data and specific column structure are unavailable, complicating immediate usability.
• The dataset focuses on a specific, ancient geological period (96-44.5 Ma), limiting direct application to modern processes.

Provenance

Source

Geoscience Australia Data

Collection Method

Compilation of seafloor spreading magnetic data, including from the 1986 R/V Rig Seismic cruise.

Time Range

96 Ma to 44.5 Ma (Mid-Cretaceous).

Freshness

null

Geography

Southern margin of Australia, between 129°E and 131.75°E, extending to Tasmania.