| Title | Victoria Island GEM Project: results from 2010 field mapping and thematic studies |
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| Author | Rainbird, R ;
Bédard, J; Dewing, K; Hadlari, T; Kiss, F; Miles, W; Ootes, L; Rayner, N; Williamson, M -C |
| Source | 38th annual Yellowknife geoscience forum, abstracts of talks and posters; 2010 p. 50-51 |
| Links | Online - En ligne
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| Image |  |
| Year | 2010 |
| Alt Series | Natural Resources Canada, Contribution Series 20230224 |
| Publisher | Northwest Territories Geological Survey |
| Meeting | Annual Yellowknife Geoscience Forum; Yellowknife; CA; November 16-18, 2010 |
| Document | serial |
| Lang. | English |
| Media | paper; digital; on-line |
| File format | pdf |
| Province | Northwest Territories |
| NTS | 67C; 67F; 67G; 77; 78A; 78B; 78C; 78D; 87; 88A; 88B; 88C; 88D |
| Area | Victoria Island |
| Lat/Long WENS | -120.0000 -100.0000 74.0000 68.0000 |
| Subjects | general geology; stratigraphy; mapping techniques; Minto Inlier |
| Program | GEM: Geo-mapping for Energy and Minerals Sverdrup Sedimentary Basin |
| Released | 2010 11 16 |
| Abstract | (unpublished)
The principal objective of the Victoria Island GEM project is to provide an improved understanding of the geology of the Minto Inlier, which has known potential for
concentrations of magmatic Ni-PGE. Close collaboration with the NWT and Nunavut geoscience offices is ensuring alignment with territoria goals. Partnerships with universities in Canada, the U.S., the U.K. and Australia has enabled training of
students, scientific input of experts, and leveraging of external resources. Summer 2010 was the first season of detailed (1:50,000) geological mapping in western Minto Inlier, located in a region centred at the head of Minto Inlet (NTS 87H/5,6,12;
87G/9,10). Field mapping identified a ca. 50 km-wide, ENE- striking, fault zone that links with a previously identified zone to the northeast. The zone is a corridor of evenly spaced horsts and grabens that offset all stratigraphic contacts
(pre-Devonian) throughout the area. The map pattern is largely controlled by the relative displacements of adjacent fault blocks, as shown by new aeromagnetic data. An older generation of NNW-striking faults may have controlled ascent of mafic magmas
of the ca. 720 Ma Franklin magmatic suite (gabbroic sills, dykes and basaltic flows) in several places. One striking example of a well preserved sill-dyke-sill system was mapped in detail and provides insights into the structure and mechanisms of
sill-dominated plumbing systems beneath large igneous provinces. The contact metamorphic aureole is unusually wide, and implies significant magmatic throughflow. A series of magnetite+sulphide skarns are developed in carbonate rocks that form the
roof of the feeder system, and extend along strike for several km. These skarns constitute favourable Au-Pt-Pd targets. Stratigraphic studies focused on detailed cliff-section description of shallow marine carbonate rocks and deeper-water shales
of the Wynniatt Formation, and of restricted basin evaporite rocks of the Minto Inlet Formation of the early Neoproterozoic Shaler Supergroup. Additionally, a continuous rock record recovered from mineral exploration drill cores was described and
sampled, enabling key gaps in the stratigraphy to be filled. New sequence boundaries were identified that will lead to a revised stratigraphic framework for correlation with adjacent inliers. Future work will focus on integrating detailed
stratigraphy and sedimentology with stable isotope stratigraphy (C, O, S), and regional facies mapping. Secondary (hydrothermal) dolomitization/silicification and related porosity development of Wynniatt carbonate units is similar to textures
preserved in the correlative Gayna River, NT, Zn-Pb deposit. Five, formation-scale, stratigraphic units are recognized within the unconformably overlying Cambro- Ordovician succession: Early Cambrian sandstone; Lower or Middle Cambrian dolostone;
Middle Cambrian mixed carbonate-clastic; Middle Cambrian to Lower Ordovician carbonate (with four locally mappable members); and an Upper Ordovician fossiliferous carbonate unit. Significant lateral variations in thickness and facies within the basal
sandstone probably were determined by paleotopography, and enhanced by the block faulting. In addition, a ca. 25 km diameter astrobleme, herein termed the Collinson Crater, was discovered near Richard Collinson Inlet on NW Victoria Island. The
crater is marked by extensive shatter cones, a concentric lake pattern, an widespread faulting. Proterozoic rocks of the Shaler Supergroup are exposed in the central crater uplift. |
| GEOSCAN ID | 332130 |
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