Apatite chemistry in Central Chilean volcanics: implications for the application of apatite as a fertility indicator for porphyry copper deposits

摘要

Accessory minerals provide valuable archives of the petrogenetic evolution of magmatic systems. Due to its ability to partition a broad suite of elements, apatite (Ca_5(PO_4)_3(OH, F, CI) has a versatile chemical composition that can act as a proxy for melt chemistry. As a result, apatite has attracted interest as both a petrogenetic indicator (Miles et al. 2013) and as an exploration tool (Mao et al. 2016). Apatites from a spatially and temporally diverse sample set from Central Chile, studied by (Hollings et al. 2005), were analysed by laser ablation inductively coupled plasma mass spectrometry and electron microprobe. These samples are unmineralised volcanic rocks that span the major porphyry copper mineralisation window in Central Chile. The aim of the study is to use apatite to track the evolution of the parental magmas of porphyry copper deposits.