Porphyry Indicator Minerals (PIMS) and Porphyry Vectoring and Fertility Tools (PVFTS) - indicators of mineralization styles and recorders of hypogene geochemical dispersion halos
Cooke, DR and Agnew, P and Hollings, P and Baker, M and Chang, Z and Wilkinson, JJ and White, NC and Zhang, L and Thompson, J and Gemmell, JB and Fox, N and Chen, H and Wilkinson, CC, Porphyry Indicator Minerals (PIMS) and Porphyry Vectoring and Fertility Tools (PVFTS) - indicators of mineralization styles and recorders of hypogene geochemical dispersion halos, Proceedings of Exploration 17: Sixth Decennial International Conference on Mineral Exploration, 22-25 October 2017, Toronto, Ontario, pp. 457-470. (2017) [Refereed Conference Paper]
Copyright 2017 the authors and Decenial Mineral Exploration Conference (DMEC)
In the past decade, significant research efforts have been devoted to mineral chemistry studies to assist porphyry exploration. These activities can be divided into two major fields of research: (1) porphyry indicator minerals (PIMS), which aims to identify the presence of, or potential for, porphyry-style mineralization based on the chemistry of magmatic minerals such as plagioclase, zircon and apatite, or resistate hydrothermal minerals such as magnetite; and (2) porphyry vectoring and fertility tools (PVFTS), which use the chemical compositions of hydrothermal minerals such as epidote, chlorite and alunite to predict the likely direction and distance to mineralized centres, and the potential metal endowment of a mineral district. This new generation of exploration tools has been enabled by advances in laser ablation-inductively coupled plasma mass spectrometry, short wave length infrared data acquisition and data processing, and the increased availability of microanalytical techniques such as cathodoluminescence. PVFTS and PIMS show considerable promise for porphyry exploration, and are starting to be applied to the diversity of environments that host porphyry and epithermal deposits around the circum-Pacific region. Industry has consistently supported development of these tools, in the case of PVFTS encouraged by several successful "blind tests" where deposit centres have successfully been predicted from distal propylitic settings. Industry adoption is steadily increasing but is restrained by a lack of the necessary analytical equipment and expertise in commercial laboratories.