| Title | Using alteration facies as proxies to metal pathways for IOCG and affiliated deposits: a global perspective from Olympic Dam and its metallogenic province to Laurentian margin examples |
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| Author | Corriveau, L ;
Blein, O; Ehrig, K; Montreuil, J -F; Potter, E; Acosta-Góngora,
P; Reid, A; Fabris, A |
| Source | GAC-MAC-IAH 2019: where geosciences converge/AGC-AMC-AIH 2019 : où les géosciences convergent; GAC-MAC-IAH Joint Meeting, Abstract volume vol. 42, 2019 p. 75  Open Access |
| Links | Online - En ligne (complete volume, volume
complet, PDF, 6.08 MB)
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| Image |  |
| Year | 2019 |
| Alt Series | Natural Resources Canada, Contribution Series 20180451 |
| Publisher | Geological Association of Canada |
| Meeting | GAC-MAC-IAH 2019 / AGC-AMC-AIH 2019; Québec, QC; CA; May 12-15, 2019 |
| Document | serial |
| Lang. | English |
| Media | on-line; digital |
| File format | pdf (Adobe® Reader®) |
| Subjects | economic geology; tectonics; geochemistry; Science and Technology; Nature and Environment; mineral exploration; mineral deposits; metasomatic deposits; skarn deposits; polymetallic ores; iron; copper;
gold; apatite; iron oxides; cobalt; bismuth; molybdenum; uranium; ore mineral genesis; mineralization; alteration; facies; fluid flow; fluid dynamics; metallogeny; tectonic setting; host rocks; albitites; bulk composition |
| Program | Targeted Geoscience Initiative (TGI-5) Uranium ore systems |
| Released | 2019 05 01 |
| Abstract | Metasomatic ore systems with iron oxide and alkali-calcic alteration form a wide variety of ore deposits, such as iron oxide-apatite (IOA), iron oxide copper-gold (IOCG), skarn and albitite-hosted
polymetallic deposits as well as their REE, Co, Bi, Mo, Re and U-rich variants. From the deep roots of the systems to surface, the alteration facies evolve from: 1) Na (albitites) and local skarns to 2) high-temperature Ca-Fe, 3) high-temperature
K-Fe, 4) transitional K (brecciated felsites) and K-Ca-Mg (K-skarns), 5) low-temperature K-Fe and Ca-Fe-Mg and 6) epithermal alteration. This prograde path - with marked changes in bulk rock composition induced by fluid-rock reactions in each facies
- and the varied permutations of alteration facies associated with tectonic telescoping, fluid mixing, periodic magma emplacement and cooling, record the various metal pathways that lead to deposits from sources to sinks. Diagnostic geochemical
footprints arise in all our case studies (e.g. Central Mineral Belt and Great Bear magmatic zone, Canada, and the Olympic Cu-Au province including Olympic Dam, Australia) that encompass 1) high intensity alteration and their prograde features, 2)
gradual alteration of protoliths at each facies, and 3) superimposition or tectonic telescoping of alteration facies. By reporting data on the IOCG discriminant diagram, it is possible to distinguish alteration zones with retrograde, tectonically
telescoped and/or cyclical metasomatic paths from least-altered host-rocks, even where their composition fall within the least-altered field. Based on this work, we interpret the footprints of the Central Mineral Belt in the Makkovik province as an
array of segmented and tectonically telescoped metasomatic paths that display, like the Bondy gneiss complex in the Grenville Province, the intrinsic characteristics of metasomatic systems that can generate IOCG, albitite-hosted U deposits and
various orogenic remobilization events. |
| Summary | (Plain Language Summary, not published)
This presentation compares the chemical footprints of the uranium-bearing metasomatic systems of the Central Mineral Belt with those of the Olympic Cu-Au
province and the giant Olympic Dam deposit in Australia. The comparison increases our ability to interpret metal pathways and deposit types within systems studied. Based on this work, we interpret the footprints of the Central Mineral Belt as an
array of segmented and telescoped metasomatic paths that display the intrinsic characteristics of metasomatic systems that can generate iron oxide copper-gold (IOCG) deposits, albitite-hosted U deposits and variants resulting from various orogenic
remobilization events. |
| GEOSCAN ID | 314560 |
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