Gold single-grain microCT scanning: operational constraints and first results in Brazilian alluvial grains

ABSTRACT

The present work sought to investigate the applicability of the microCT scanning beyond petrophysics in oil and gas industry. We analysed external features (morphology) with all their nuances, and internal features such as mineral inclusions and vugs, in micrometric alluvial gold grains from one of the largest rivers in Southeastern Brazil. Owing to the complicated X-ray interactions with any metallic material, mainly gold, several imaging protocols were used until obtaining the most appropriate one. The results corroborate that microCT scanning can be a useful tool in provenance studies of detrital gold grains, even in an adverse analytical context and with small gold grain populations.

KEYWORDS:

• MicroCT scanning
• gold single-grain microtomography
• alluvial gold
• gold provenance

Acknowledgements

The authors are grateful for the use of the following laboratories: Laboratório Geológico de Preparação de Amostras, UERJ; Laboratório Multiusuário de Caracterização Tecnológica, Centro de Tecnologia Mineral; and Ingrain Lab, HBTC. The resources for field work were provided by the Fundação Amparo à Pesquisa do RJ, FAPERJ. MH and MT acknowledge financial support by the Brazilian Research Council (CNPq) and FAPERJ.

Disclosure statement

No potential conflict of interest was reported by the author(s).