Cape Leeuwin Manganese Nodule Deposit Survey Data

A 1976 research cruise by HMAS Diamantina collected about 2000 manganese nodules from the Indian Ocean floor southwest of Cape Leeuwin, Western Australia. The survey targeted a deposit initially discovered in 1970 and estimated to cover approximately 900,000 square kilometers. The work was conducted by researchers associated with the Australian Ocean Data Network.

Use Cases

• Analyze nodule chemistry and mineralogy from the approximately 2000 collected samples to assess resource potential. Map the distribution of the deposit using data from about 20 photographic stations and 8 successful sampling stations. Correlate nodule presence with seafloor features like ripple marks and scour marks to model past and present bottom current strength. Estimate sedimentation rates by studying disconformities in sediment cores recovered alongside nodules.

Strengths

• Approximately 2000 physical nodule samples collected for analysis.
• Survey area covers an estimated 900,000 square kilometers based on prior photographic evidence.
• Data integrates multiple modalities: bottom photographs, sediment cores, and physical nodule samples.

Limitations

• Small number of direct sampling stations (8 successful stations).
• Positioning by celestial navigation may have errors up to 10 km, affecting station relocation accuracy.
• Data is historical, collected during a single cruise in 1976, with no indication of updates.

Provenance

Source

Australian Ocean Data Network

Collection Method

Sampling via light box dredge during a 10-day research cruise aboard HMAS Diamantina; prior discovery based on bottom photographs from USNS Eltanin.

Time Range

Primary sampling occurred in 1976; initial discovery was in 1970.

Geography

Indian Ocean floor southwest of Cape Leeuwin, Western Australia.