| Title | Topographic features of the sub-Athabasca Group unconformity surface in the southeastern Athabasca Basin and their relationship to uranium ore deposits |
| Author | Li, Z; Bethune, K M; Chi, G; Bosman, S A; Card, C D |
| Source | Canadian Journal of Earth Sciences vol. 52, 2015 p. 903-920, https://doi.org/10.1139/cjes-2015-0048 (Open Access) |
| Year | 2015 |
| Alt Series | Earth Sciences Sector, Contribution Series 20160023 |
| Publisher | Canadian Science Publishing |
| Document | serial |
| Lang. | English |
| Media | digital; on-line |
| File format | pdf |
| Province | Saskatchewan |
| NTS | 74A/13; 74G/01; 74G/08; 74H/03; 74H/04; 74H/05; 74H/06; 74H/07; 74H/10; 74H/11; 74H/12; 74H/13; 74H/14; 74H/15; 74I/03; 74I/04 |
| Area | Key Lake; Millennium; McArthur River |
| Lat/Long WENS | -106.5000 -104.5000 58.2500 56.7500 |
| Subjects | economic geology; radioactive minerals; unconformity-type deposit; unconformities; uranium deposits; uranium; mineral deposits; mineral occurrences; mineralization; models; modelling; formation fluids;
fluid dynamics; fluid flow; Athabasca Basin |
| Illustrations | location maps; models; rose diagrams |
| Program | Targeted
Geoscience Initiative (TGI-4), Uranium Ore Systems |
| Abstract | Topographic features of the sub-Athabasca unconformity surface, such as paleovalleys, topographic highs, and fault scarps, have been documented locally in the eastern Athabasca Basin, and available data
indicate that they are spatially associated with mineralization. However, the mechanisms by which such topographic features were generated, their size and distribution at the regional scale, as well as their relationship to mineralization, are still
not completely understood. A 100 by 60 square kilometre area of the southeastern Athabasca Basin, encompassing the McArthur River, Phoenix, and Key Lake deposits, was selected to study the relationship between these topographic features and U
mineralization. In this region three dominant sets of sub-vertical faults were identified on the basis of aeromagnetic data: northeast-trending, north-northwesttrending, and northwest-trending. A detailed three-dimensional (3-D) model of this part of
the basin was constructed using data from more than 1200 drill holes. This model reveals numerous dominantly northeast-trending ridges and valleys in the unconformity surface. Among these, a prominent northeast-trending ridge is situated close to the
McArthur River - Key Lake deposits trend. Structural interpretation and cross-sections illustrate that the topographic features that have been documented in previous studies are a function of three principal factors: (i) pre-Athabasca group
ductile-brittle faulting and alteration; (ii) differential weathering and erosion; and (iii) syn- to post-Athabasca ductile-brittle reactivation of pre-existing graphite-rich ductile shear zones. The topographic features and associated faults may
have acted as conduits and barriers to fluid flow and thus controlled alteration patterns and uranium mineralization. |
| GEOSCAN ID | 298714 |
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