Leg 189 Synthesis: Cretaceous-Holocene Marine Sediment Cores from the Tasmanian Gateway

Tasmanian Gateway marine sediment cores from five Ocean Drilling Program sites, totaling 4539 meters recovered with an 89% recovery rate. The dataset contains upper Maastrichtian to Holocene sequences, including mudstones, siltstones, and carbonates, to study the opening of the gateway and its link to Antarctic cooling. Data was aggregated by Geoscience Australia and last updated in March 2026.

Use Cases

• Modeling the timing and impact of the Antarctic Circumpolar Current onset based on sediment composition changes.
• Analyzing paleoenvironmental shifts from siliciclastic to carbonate deposition linked to gateway opening.
• Reconstructing high-latitude temperature trends based on palynomorph and diatom evidence in mudstones.
• Studying Neogene pelagic carbonate accumulation patterns north of the Polar Front.

Strengths

• 4539 meters of largely continuous core material with a documented 89% recovery rate.
• Temporal coverage spans from the Late Cretaceous (Maastrichtian) to the Holocene.
• Sediment composition is explicitly described (mudstones, glauconitic siltstones, pelagic carbonates).

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count and file size are unknown, which may limit suitability assessment.

Provenance

Source

Geoscience Australia Data

Collection Method

Core samples collected via Ocean Drilling Program (ODP) Leg 189.

Time Range

Upper Maastrichtian to Holocene (~72 million years to present).

Freshness

Last updated 2026-03 25 16:09:55.381250; freshness should be verified.

Geography

Bathyal depths on submerged continental blocks in the Tasmanian Gateway, Southern Ocean.