Igneous and Sedimentary Rocks Dredged from the Northern Macquarie Ridge

Altered basalt, dolerite, and gabbro were collected from a previously unsampled portion of the Macquarie Ridge (47°-48° S). These rocks, dredged using the commercial fishing vessel Amaltal Explorer, show petrographic and geochemical similarity to MORB-like suites found further south along the ridge. The data suggests the northern ridge is geologically related to the rest of the ridge, despite its bathymetric connection to the New Zealand continental shelf.

Use Cases

• Classifying rock types based on petrographic descriptions of altered basalt, dolerite, and gabbro.
• Analyzing geochemical signatures to infer petrological affinity, such as MORB-like characteristics.
• Investigating geological relationships and tectonic history between the Macquarie Ridge and the New Zealand continental shelf.
• Studying sediment provenance by identifying contributions from both oceanic ridge and continental sources.

Strengths

• Data originates from a previously unsampled portion of the Macquarie Ridge, providing new geological insights.
• Rocks are described with specific petrographic and geochemical analysis, allowing for detailed comparison.
• Findings directly address the geological relationship between different segments of the ridge and adjacent continental shelf.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• Data is presented in PDF and HTML formats, which may require extraction for computational analysis.

Provenance

Source

Geoscience Australia Data

Collection Method

Rocks were dredged from the seafloor using the commercial fishing vessel Amaltal Explorer.

Freshness

Last updated 2026-04-30 12:58:53.751174; freshness should be verified.

Geography

Northern Macquarie Ridge, Southern Ocean (47°-48° S).