Belousova,E.A., Griffin,W.L., O'Reilly,S.Y. and Fisher,N.I.(2002): Apatite as an indicator mineral for mineral exploration: trace-element compositions and their relationship to host rock type. Journal of Geochemical Exploration, 76, 45-69.

『鉱物探査のための指示鉱物としてのアパタイト（燐灰石）：微量元素組成とその母岩との関係』

『Abstract
　Over 700 apatite grains from a range of rock types have been analysed by laser-ablation microprobe ICOMS for 28 trace elements, to investigate the potential usefulness of apatite as an indicator mineral in mineral exploration. Apatites derived from different rock types have distinctive absolute and relative abundances of many trace elements (including rare-earth elements (REE), Sr, Y, Mn, Th), and chondrite-normalised trace-element patterns. The slope of chondrite-normalised REE patterns varies systematically from ultramafic through mafic/intermediate to highly fractionated granitoid rock types. (Ce/Yb)cn is very high in apatites from carbonatites and mantle-derived lherzolites (over 100 and over 200, respectively), while (Ce/Yb)cn values in apatites from granitic pegmatites are generally less than 1, reflecting both HREE enrichment and LREE delpetion. Within a large suite of apatites from granitoid rocks, chemical composition is closely related to both the degree of fractionation and the oxidation state of the magma, two important parameters in determining the mineral potential of the magmatic system. Apatite can accept high levels of transition and chalcophile elements and As, making it feasible to recognise apatite associated with specific types of mineralisation. Multivariate statistical analysis has provided a user-friendly scheme to distinguish apatites from different rock types, based on contents of Sr, Y, Mn and total REE, the degree of LREE enrichment and the size of the Eu anomaly. The scheme can be used for the recognition of apatites from specific rock types or styles of mineralisation, so that the provenance of apatite grains in heavy mineral concentrates can be determined and used in geochemical exploration.

Keywords: apatite; Apatite trace elements; Apatite discriminant diagrams; Apatite classification; Apatite regression tree』

1. Introduction
2. Sampling
　2.1. Granitoid rocks
　2.2. Granite pegmatites
　2.3. Larvikite (syenite)
　2.4. Dolerite
　2.5. Carbonatites
　2.6. Apatite-iron ore deposits
　2.7. Mantle-derived peridotite xenoliths
3. Analytical techniques
　3.1. Cathodoluminescence microscopy
　3.2. Cameca VAMEBAX SX50 electron microprobe
　3.3. Laser ablation ICPMS microprobe
4. Results
5. Discussion
　5.1. Patterns in the data
　5.2. Discriminant plots
　5.3. Statistical analysis (CART)
　5.4. Oxidation state
　5.5. Apatite as an indicator mineral
6. Conclusions
Acknowledgements
References

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