|Title||Petrogenesis of the ferrogabbroic intrusions and associated Fe-Ti-V-(P) mineralization within the McFaulds greenstone belt, Superior Province, northern Ontario|
|Licence||Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences.|
|Author||Kuzmich, B; Hollings, P; Houlé, M G|
|Source||Targeted Geoscience Initiative 4: Canadian nickel-copper-platinum group elements-chromium ore systems -- fertility, pathfinders, new and revised models; by Ames, D E (ed.); Houlé, M G (ed.); Geological Survey of Canada, Open File 7856, 2015 p.
115-123, https://doi.org/10.4095/296683 Open Access|
|Publisher||Natural Resources Canada|
|Related||This publication is contained in Targeted Geoscience
Initiative 4: Canadian nickel-copper-platinum group elements-chromium ore systems -- fertility, pathfinders, new and revised models |
|NTS||43C/05; 43C/12; 43C/13; 43D/06; 43D/07; 43D/08; 43D/09; 43D/10; 43D/11; 43D/14; 43D/15; 43D/16; 43E/01; 43E/02; 43E/03; 43F/04|
|Lat/Long WENS|| -87.5000 -85.5000 52.2500 51.2500|
|Subjects||metallic minerals; igneous and metamorphic petrology; geochemistry; geophysics; mineralization; petrogenesis; lithology; metallogeny; iron; total field magnetics; lithofacies; petrographic analyses;
whole rock geochemistry; whole rock analyses; trace element geochemistry; McFaulds Lake greenstone belt; Superior Province; Butler intrusion; Thunderbird intrusion; Precambrian|
|Program||Targeted Geoscience Initiative (TGI-4) Mafic-Ultramafic Ore Systems|
|Released||2015 06 22; 2023 03 17|
|Abstract||The Thunderbird and Butler intrusions of the McFaulds Lake greenstone belt ("Ring of Fire") were studied to determine petrogenesis and associated Fe-Ti-V-(P) mineralization. These intrusions are
characterized by variably well layered gabbro-anorthosite intrusions with abundant Fe-Ti oxides, broadly termed ferrogabbro. The layers are composed of partial to complete cycles that comprise basal massive oxide (magnetiteilmenite), which grade into
semi-massive oxide units, followed by oxide-rich pyroxenite/melagabbro/gabbro, oxide-poor melagabbro/gabbro/leucogabbro, and topped with oxide-free leucogabbro/anorthosite. The cycles range from centimetres to metres in thickness and define the well
layered portions of the intrusions that typically exhibit sharp upper and lower contacts with gradational internal contacts. Conversely, the intrusions contain broad intervals of disseminated magnetite-ilmenite (2–5%) hosted in melagabbro/gabbro/
leucogabbro/anorthosite, which range in thickness from metres to tens of metres. The layering and textures observed within the ferrogabbro units are thought to be dominantly produced by convection currents with intermittent periods of
The ferrogabbro intrusions are characterized by gently sloping LREE and flat HREE patterns. This geochemical signature most closely corresponds to an E-MORB source that is thought to have been the result of interaction of a mnalte
plume with MORB-like mantle under the McFaulds Lake area. This plume-related magma is thought to have undergone differentiation, resulting in the abundant Cr-Ni-Cu-PGE-bearing ultramafic and evolved Fe-Ti-rich mafic suites in the McFaulds area.
Additionally, the plume may have resulted in a thinned lithosphere and produced the coeval VMS occurrences.
Also studied is the potential application of the TiO2/V2O5 ratio for the identification of prospective vanadium mineralization and to aid
in the determination of magmatic stratigraphy.
|Summary||(Plain Language Summary, not published)|
The Targeted Geoscience Initiative (TGI-4) 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 volume summarizes 22 research activities completed under the TGI-4 Ni-Cu-PGE-Cr ore systems project that focused on
revised and new geologic models for Ni-Cu-PGE, PGE-Cu and Cr deposits, innovative techniques for determining potential fertility of intrusion (Ni-Cu-PGE), and defining pathfinders for Ni-Cu-PGE mineralization.