| Title | The evolution of metasomatic uranium ore systems in the Kitts-Post Hill belt of the Central Mineral Belt, Labrador |
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| Author | Duffett, C L; Potter, E G ; Petts, D C; Acosta-Gongóra, P; Cousens, B L; Sparkes, G W |
| Source | Ore Geology Reviews vol. 126, 103720, 2020 p. 1-22, https://doi.org/10.1016/j.oregeorev.2020.103720 |
| Image |  |
| Year | 2020 |
| Alt Series | Natural Resources Canada, Contribution Series 20200029 |
| Publisher | Elsevier B.V. |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf; html |
| Province | Newfoundland and Labrador |
| Area | Labrador; Canada |
| Lat/Long WENS | -61.9736 -58.2639 55.8628 54.5847 |
| Subjects | economic geology; geochemistry; Science and Technology; mineral deposits; metasomatic deposits; uranium; mineralization; ore mineral genesis; tectonic setting; orogenies; shear zones; trace element
geochemistry; major element geochemistry; Central Mineral Belt; Kitts-Post Hill Belt; Post Hill Group; Paleoproterozoic; Precambrian; Proterozoic |
| Illustrations | location maps; geoscientific sketch maps; schematic cross-sections; tables; schematic representations; photomicrographs; plots |
| Program | Targeted Geoscience Initiative (TGI-5) Uranium ore systems - deep metasomatic processes |
| Released | 2020 08 14 |
| Abstract | Uranium mineralization of the Kitts-Post Hill belt of the Central Mineral Belt is concentrated in the upper portion of the Post Hill Group, along a structurally complex shear zone located within the
Makkovik Province of Labrador. Recent research in the CMB has highlighted regional-to deposit-scale Na, Ca-Fe, K- and K-Fe alteration, as well as local hydrothermal breccia; all characteristic of iron oxide and alkali-calcic alteration systems that
host iron oxide-copper-gold (IOCG) and affiliated deposits. Least-altered uraninite grains from occurrences in Kitts-Post Hill belt contain elevated Th, Zr, Y and rare earth element (REE) contents, implying primary uranium mineralization from
alkaline fluids capable of transporting high field strength elements. In quantitative LA-ICP-MS maps, remobilization of U, Pb and light-REE along grain boundaries and fractures coupled with zones of elevated Zr, and lower Th and REE contents record
element leaching during alteration and/or recrystallization. In chondrite-normalized plots of uraninite, contrasting REE signatures also imply three populations along the corridor that formed at different temperatures and physico-chemical conditions.
Leaching of light-REE from the uraninite grains support recent studies indicating REE signatures can be disturbed by under certain conditions while heavy-REE signatures remain intact. The inferred contrasting fluid sources, reflected in the major and
trace element composition of uraninite reveal a complex fluid history, complicated by post-ore magmatism and metamorphism. |
| Summary | (Plain Language Summary, not published)
This report summaries research on the formation of uranium mineralization of the Kitts-Post Hill belt of the Central Mineral Belt, Labrador. Recent
research in the CMB has highlighted regional-to deposit-scale Na, Ca-Fe, K- and K-Fe alteration, as well as local hydrothermal breccia; all characteristic of iron oxide and alkali-calcic alteration systems that host iron oxide-copper-gold (IOCG) and
affiliated deposits. Based on petrography and trace element chemistry of the mineral uraninite, the mineralization exhibits features characteristic of IOCG and affiliated deposits. However, leaching of light-REE from the uraninite grains support
recent studies indicating REE signatures can be disturbed by under certain conditions while heavy-REE signatures remain intact. The inferred contrasting fluid sources, reflected in the major and trace element composition of uraninite reveal a complex
fluid history, complicated by post-ore magmatism and metamorphism. |
| GEOSCAN ID | 325460 |
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