| Title | 40Ar/39Ar hornblende and biotite cooling ages for metaplutonic rocks of the central Thelon Tectonic Zone, Nunavut |
| Download | Downloads |
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| Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
| Author | Camacho, A; Berman, R G ; Sanborn-Barrie, M |
| Source | Geological Survey of Canada, Open File 8625, 2020, 77 pages, https://doi.org/10.4095/315135  Open Access |
| Image |  |
| Year | 2020 |
| Publisher | Natural Resources Canada |
| Document | open file |
| Lang. | English |
| Media | on-line; digital |
| File format | readme
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| File format | pdf (Adobe® Reader®); rtf; xlsx (Microsoft® Excel®) |
| Province | Nunavut |
| NTS | 76H; 76I |
| Area | Duggan Lake; Overby Lake; Queen Maud Migratory Bird Sanctuary; Ellice River; Thelon Wildlife Sanctuary; Back River |
| Lat/Long WENS | -106.0000 -104.0000 67.0000 65.0000 |
| Subjects | regional geology; geochronology; tectonics; Science and Technology; radiometric dating; argon argon dating; mass spectrometer analysis; thermal history; tectonic evolution; metamorphism; models;
hornblende; biotite; bedrock geology; basement geology; lithology; metamorphic rocks; granodiorites; monzonites; monzo-granites; diorites; monzodiorites; gabbros; tonalites; Archean; Canadian Shield; Thelon Tectonic Zone; Rae Craton; Queen Maud
block; Slave Craton; Overby Lake Domain; Ellice River Domain; Duggan Lake Domain; Bathurst Fault; Yellowknife Supergroup; Precambrian; Proterozoic |
| Illustrations | location maps; geoscientific sketch maps; bar graphs |
| Program | GEM2: Geo-mapping for Energy and Minerals Rae Province, Chantrey-Thelon |
| Released | 2020 01 06 |
| Summary | (Plain Language Summary, not published)
Forty-three 40Ar/39Ar cooling ages of single crystals of hornblende and biotite were obtained from metaplutonic rock samples across the central Thelon
tectonic zone (Ttz), adjacent eastern Slave craton, and western Rae craton. The oldest hornblende (2.49 Ga) and biotite (1.98 Ga) ages occur in the Slave craton; this biotite age coincides with the time of widespread Ttz plutonism, somewhat earlier
than the 1.97 Ga time of the Slave-Rae collision previously proposed. Widespread ca. 1.89-1.87 Ga hornblende ages across much of the central Ttz and western Rae craton reflect cooling through ~550°C at this time. The southern regions of the Western
and Central plutonic belts record younger hornblende ages (ca. 1.83-1.80 Ga) indicating this region remained at a deeper crustal level and cooled through ~550°C some 40-65 million years later. These cooling age contrasts reflect diachronous
exhumation which appears to be influenced by NW-trending structures parallel to the Bathurst fault. |
| GEOSCAN ID | 315135 |
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