| Title | Fluid evolution along the Patterson Lake corridor in the southwestern Athabasca Basin: constraints from fluid inclusions and implications for unconformity-related uranium mineralization |
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| Author | Rabiei, M; Chi, G ; Potter, E G; Tschirhart, V; MacKay, C; Frostad, S; McElroy, R; Ashley, R; McEwan, B |
| Source | A new unconformity-related uranium district: the Patterson Lake Corridor, Athabasca Basin Canada; by Potter, E (ed.); Tschirhart, V (ed.); Powell, J (ed.); Geochemistry: Exploration, Environment, Analysis vol. 21, issue 3, 2021 p. 1-22, https://doi.org/10.1144/geochem2020-029 |
| Image |  |
| Year | 2021 |
| Alt Series | Natural Resources Canada, Contribution Series 20200756 |
| Publisher | Geological Society of London |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Saskatchewan |
| NTS | 74E/07; 74E/08; 74E/09; 74E/10; 74E/15; 74E/16; 74F/05; 74F/06; 74F/07; 74F/10; 74F/11; 74F/12; 74F/13; 74F/14; 74F/15 |
| Lat/Long WENS | -109.6000 -108.8500 57.8167 57.4667 |
| Subjects | economic geology; geochemistry; Science and Technology; Nature and Environment; mineral exploration; exploration methods; mineral deposits; uranium; unconformity-type deposit; mineralization; ore
mineral genesis; ore controls; fluid dynamics; fluid inclusions; salinity; quartz; thermal analyses; tectonic history; faulting; hydrothermal systems; fluid flow; pressure-temperature conditions; graphite; bedrock geology; basement geology;
lithology; metamorphic rocks; gneisses; paragenesis; petrography; alteration; Athabasca Basin; Patterson Lake Corridor |
| Illustrations | location maps; geoscientific sketch maps; geochronological charts; photographs; photomicrographs; schematic representations; ternary diagrams; plots; bar graphs; profiles; models; phase
diagrams |
| Program | Targeted Geoscience Initiative (TGI-5) Uranium ore systems - fluid pathways |
| Released | 2021 08 23 |
| Abstract | The Patterson Lake corridor (PLC) in the southwestern margin of the Athabasca Basin hosts several high-grade uranium deposits. These deposits are located in the basement up to 900 m below the
unconformity surface, raising questions about their affiliation with typical unconformity-related uranium (URU) deposits elsewhere in the basin. Based on cross-cutting relationships four pre- and three syn- to post-mineralization quartz generations
were identified. Fluid inclusion analyses indicate that pre-mineralization fluids have salinities ranging from 0.2 to 27.2 wt% NaCl equiv. (avg. 9.0 wt%), whereas syn-mineralization fluids have salinities ranging from 8.8 to 33.8 wt% NaCl + CaCl2
(avg. 25.4 wt%), with NaCl- and CaCl2-rich varieties. The homogenization temperatures (Th) of fluid inclusions from pre-mineralization quartz range from 80 to 244°C (avg. 147°C), and from syn-mineralization quartz range from 64 to 248°C (avg. 128°C).
Fluid boiling is indicated by the co-development of liquid-dominated and vapour-dominated fluid inclusions within individual fluid inclusion assemblages from the syn-mineralization quartz and is related to episodic fluid pressure drops caused by
reactivation of basement faults. Our results indicate that composition and P-T conditions of the ore fluids in the PLC are comparable to those of typical URU deposits in the Athabasca Basin, indicating that the uranium deposits in the PLC formed
under similar hydrothermal conditions. Episodic reactivation of basement faults was an important driving force to draw uraniferous fluids from the basin and reducing fluids from the basement to the mineralization sites, forming deep basement-hosted
deposits. |
| Summary | (Plain Language Summary, not published)
The Targeted Geoscience Initiative (TGI) is a collaborative federal geoscience program that provides industry with the next generation of geoscience
knowledge and innovative techniques to better detect buried mineral deposits, thereby reducing some of the risks of exploration. This contribution outlines the chemistry of fluid inclusions trapped in the mineral quartz before, during and after
formation of the recently discovered Patterson Lake Corridor uranium deposits (Triple R, Arrow, Spitfire). The data are comparable to typical unconformity-related uranium deposits of the Athabasca Basin, suggesting that the Patterson Lake deposits
formed under similar hydrothermal conditions and maybe classified as such despite the deep depth from the unconformity surface. |
| GEOSCAN ID | 328127 |
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