Apatite chemistry - a potential tool for IOCG exploration
2006 (English)In: The 27th Nordic Geological Winter Meeting, January 9-12, 2006, Oulu, Finland: abstract volume / [ed] Petri Peltonen ; Antti Pasanen, Helsinki: Geological Society of Finland , 2006, 29- p.Conference paper, Meeting abstract (Other academic)
Northern Norrbotten is an important mining region of Sweden and is regarded as an iron-oxide copper-gold (IOCG) district hosting several apatite-iron oxide and copper-gold sulphide ores (e.g. Hitzman et. al., 1992). The IOCG group of deposits is diverse with respect to age, host rock, ore and alteration mineralogy as well as ore-forming processes and there is still an ongoing debate regarding a possible genetic link between "classical" Kiruna type ores and copper dominated end-members within this class of deposits. Apatites from Kiruna-type apatite-iron deposits (Kiirunavaara, Rektorn, Nukutus, Ekströmsberg, Tjårrojåkka-Fe), IOCG copper occurrences (Tjårrojåkka-Cu and Nautanen), a 1.89 Ga andesite and a Perthite-monzonite group intrusion were collected and analysed for their mineral chemistry and rare earth elements using electron microprobe and LA-ICPMS analysis. The apatite chemistry can subsequently be used as an indicator of the composition of fluids involved in the formation of the deposits (Korzhinskiy, 1982). Different trends with regard to F-Cl content as well as REE pattern in the apatites were observed for apatite-iron ores with no spatial relation to copper mineralisation compared to the apatite-iron ore spatially related to a copper occurrence. The apatites from the former were almost pure F-apatites with steep REE patterns, while the apatites from the latter and the copper mineralisations themselves contained a large Cl-component and showed depletion in LREE.It can be concluded that apatite chemistry could be a potential tool for distinguishing copper mineralising apatite-iron systems from barren ones. However, so far only one apatite-iron deposit spatially related to a copper occurrence has been studied and more studies are needed to confirm the results.
Place, publisher, year, edition, pages
Helsinki: Geological Society of Finland , 2006. 29- p.
, Bulletin of the Geological society of Finland, ISSN 0367-5211 ; Special issue 1
Research subject Ore Geology
IdentifiersURN: urn:nbn:se:ltu:diva-39076Local ID: daf51040-ee8b-11db-bb5c-000ea68e967bOAI: oai:DiVA.org:ltu-39076DiVA: diva2:1012584
Nordic Geological Winter Meeting : 09/01/2006 - 12/01/2006
Godkänd; 2006; 20111007 (andbra)2016-10-032016-10-03Bibliographically approved