| Title | Paleoproterozoic gold and its tectonic triggers and traps |
| Download | Download (whole publication) |
| |
| Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
| Author | Lawley, C J M ;
Davis, W J; Jackson, S E; Petts, D C; Yang, E; Zhang, S; Selby, D; O'Connor, A R; Schneider, D A |
| Source | Targeted Geoscience Initiative: 2018 report of activities; by Rogers, N (ed.); Geological Survey of Canada, Open File 8549, 2019 p. 71-75, https://doi.org/10.4095/313641  Open Access |
| Year | 2019 |
| Publisher | Natural Resources Canada |
| Document | open file |
| Lang. | English |
| Media | on-line; digital |
| Related | This publication is contained in Targeted Geoscience
Initiative: 2018 report of activities |
| File format | pdf |
| Province | Manitoba |
| NTS | 64B/12; 64B/13; 64C/09; 64C/10; 64C/11; 64C/12; 64C/13; 64C/14; 64C/15; 64C/16; 64D/09; 64D/16; 64E/01; 64F/01; 64F/02; 64F/03; 64F/04; 64G/04 |
| Area | Leaf Rapids; Lynn Lake |
| Lat/Long WENS | -102.0833 -99.7500 57.1667 56.5000 |
| Subjects | economic geology; tectonics; structural geology; geochronology; mineral deposits; gold; mineral exploration; modelling; ore controls; ore mineral genesis; mineralization; field relations; greenstone
belts; tectonic setting; tectonic history; magmatism; deformation; metamorphism; orogenesis; intrusions; dykes; sills; mineral assemblages; fabric analyses; veins; veinlets; thermal analyses; radiometric dating; bedrock geology; structural features;
folds; faults; lithology; Paleoproterozoic; Lynn Lake Greenstone Belt; MacLellan gold deposit; Hearne-La Ronge-Lynn Lake Block; Sask Craton; Superior Province; Hearne Craton; Superior Craton; Trans-hudson Orogeny; Sickle Group; Ralph Lake
conglemates; Burntwood Group; Wasekwan Group; Pool Lake Intrusive Suite; Eden Carbonatite; Wathaman Suite; Precambrian; Proterozoic |
| Illustrations | geological sketch maps; schematic sections; photomicrographs |
| Program | Targeted Geoscience Initiative (TGI-5) Knowledge Management Coordination |
| Program | Targeted Geoscience Initiative (TGI-5) Gold ore systems - tectonic drivers and conduits |
| Program | Targeted Geoscience Initiative (TGI-5) Gold ore systems - System Controls - Time and Space |
| Released | 2019 03 01 |
| Abstract | The tectonic trigger(s) that controls the formation of large gold deposits hosted within ancient greenstone belts re-main poorly understood. Herein we address that knowledge gap by merging macro- to
micro-scale field relationships and multiple mineral chronometers to constrain the timing of magmatism, deformation, metamorphism, and gold in the Lynn Lake greenstone belt, Manitoba. Preliminary monazite and xenotime ages from the MacLellan gold
deposit (1.83-1.75 Ga) are coeval with previously reported metamorphic ages for northern Manitoba (1.81-1.78 Ga), which also marks the terminal collision of the composite Hearne-La Ronge-Lynn Lake block and Sask-Superior craton at 1.83 to 1.80 Ga.
The peak metamorphic mineral assemblage and dated phosphate minerals define the main structural fabric (D2) of the Lynn Lake greenstone belt, which coupled with the folded, transposed auriferous veins, places a lower limit for the timing of gold at
or before 1.75 Ga. However, xenotime within a garnet-hosted and gold-bearing veinlet dated at ca. 1.83 Ga may provide the first evidence for a cryptic early stage of gold mineralization that is coeval with the onset of collisional orogenesis between
the composite Hearne and Superior cratons. Ongoing thermo-chronology (e.g. apatite, biotite) and Re-Os pyrite and arsenopyrite dating at gold deposits within the Lynn Lake greenstone belt will further constrain the timing of gold deposition relative
to the different stages of the Trans-Hudson orogeny. New ages will inform ore system models by identifying the tectonic trigger(s) for gold and improving exploration targeting in ancient greenstone belts. |
| Summary | (Plain Language Summary, not published)
The Targeted Geoscience Initiative (TGI) is directed towards providing next generation knowledge and methods to facilitate more effective targeting of
buried mineral deposits. The program aims to enhance the effectiveness of exploration for Canada's major mineral systems by resolving foundational geoscience problems that constrain the geological processes responsible for the liberation metals from
their source region, transportation of these ore metals and control their eventual deposition. TGI supports projects on gold, Ni-Cr-PGE, porphyry-style mineralization, uranium and volcanic- and sedimentary-hosted base metal mineralization ore
systems, with each project divided into subprojects focused on resolving specific knowledge gaps by integrating data and studies from multiple sites across Canada. Herein, we present interim results and interpretations from a selection of the
research activities currently being conducted under the auspices of TGI. |
| GEOSCAN ID | 313641 |
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