Thunderbird heavy mineral sand deposit, Western Australia

Abstract

The Thunderbird heavy mineral sand deposit is located in Canning Basin of Western Australia and is hosted by Jurassic-Cretaceous fine sands and silts. The large areal extent, width, grade, geological continuity and grainsize of the Thunderbird deposit are interpreted to have formed in an off-shore, sub-wave base depositional environment. The Thunderbird mineralisation is hosted within a well-sorted and rounded fine to very-fine-grained sand unit which is over 90 m thick and contains abundant heavy minerals (up to 40% HM). Mineralisation occurs as a thick, broad sheet-like body striking northwest, and dipping shallowly to the west and southwest, extending from surface to a maximum drilled depth of 155 m. The heavy minerals suite in the Thunderbird deposit is comprised of altered ilmenite, ilmenite, pseudorutile, haematite, goethite, leucoxene, zircon, rutile, anatase and monazite, with very minor amounts of tourmaline, spinel, staurolite and andalusite. The minerals are finer-grained than most deposits currently being mined.

Keywords:

• Mineral sands
• Placers
• Deposit studies

Acknowledgements

The authors acknowledge the contributions of Sheffield geologist Ms Diane Bréant and Consultant Dr Joseph Drake-Brockman and thank the directors of Sheffield Resources for permission to publish this paper.