Notes on heavy mineral sands on Gulf St Vincent and Encounter Bay beaches, South Australia

ABSTRACT

Coloured heavy mineral sands are a conspicuous yet somewhat ephemeral feature on the surface of many beaches around Gulf St Vincent and in Encounter Bay in South Australia. The ultimate origin of the minerals continues to be investigated, but they are known to be important constituents of an extensive suite of Carboniferous to Permian glacigene sediments deposited over most of the region. They occur in Palaeogene palaeochannel sands as well as within overlying Pleistocene alluvial sediments and soils. It is the continued erosion of these sediments that has fed the heavy minerals into modern terrestrial landscapes and concentrated them in small-scale placer sands on the beaches around Gulf St Vincent.

KEYWORDS:

• Heavy minerals
• gem sands
• placer deposits
• beach sands
• mineral provenance

Acknowledgments

Comments by two reviewers on the original manuscript are gratefully acknowledged.

Disclosure statement

The author is not aware of any potential conflict of interest.