"Apatitites" - their origin and genetic relation to the Fe-oxide-apatite ores of the Bafq District, Iran. A key feature to the understanding of the genesis of the Kiruna-type Ores

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Kiruna-type apatite¿iron oxide deposits and iron-oxide¿Cu¿Au deposits are possibly end-members of a continuum and represent economically important resources with little-understood origins. A prominent example are the world-class iron-oxide¿apatite ores of the Bafq district, Iran, which are coeval with a wide variety of unusual rare earth element (REE)-bearing apatite-rich magmatic and/or hydrothermal rocks called ¿apatitites¿ here. Our understanding of this type of apatite¿Fe-oxide ore mineralization is obscured by fundamental disagreement on key issues, particularly with regard to their relation with magma-types and the source of ore-forming fluids. In order to contribute to the resolution of this controversy we propose to carry out a detailed study on the mineralogy and geochemistry of the Bafq apatitites as well as on fluid inclusions in their apatites and minerals from the Fe oxide¿apatite ores in order to trace the complex nature of progressive geochemical and mineralogical changes (paragenetic association, alteration) with element enrichments (mineralization processes) and the formation of the REE-rich apatite and the Fe-oxides. The isotopic composition of ore minerals (in particular apatite) and related rocks is expected to provide information on the fluid source and on the age of ore mineralization. From this study we expect to learn how and from which source materials these deposits formed.