| Title | Indicator minerals in fine-fraction till heavy-mineral concentrates determined by automated mineral analysis: examples from two Canadian polymetallic base-metal deposits |
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| Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
| Author | Lougheed, H D; McClenaghan, M B ; Layton-Matthews, D; Leybourne, M I |
| Source | Targeted Geoscience Initiative 5: volcanic- and sediment-hosted massive-sulfide deposit genesis and exploration methods; by Peter, J M (ed.); Gadd, M G (ed.); Geological Survey of Canada, Bulletin 617, 2022 p. 247-286, https://doi.org/10.4095/328011
 Open Access |
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| Year | 2022 |
| Publisher | Natural Resources Canada |
| Document | serial |
| Lang. | English |
| Media | on-line; digital |
| Related | This publication is contained in Targeted Geoscience
Initiative 5: volcanic- and sediment-hosted massive-sulfide deposit genesis and exploration methods |
| File format | pdf |
| Province | Nunavut; New Brunswick |
| NTS | 21J/02; 21J/03; 21J/06; 21J/07; 86A/10 |
| Area | Izok Lake; Nashwaak River |
| Lat/Long WENS | -113.0000 -112.7167 65.6833 65.6167 |
| Lat/Long WENS | -67.1000 -66.9167 46.4167 46.2167 |
| Subjects | economic geology; surficial geology/geomorphology; mineralogy; Science and Technology; Nature and Environment; mineral exploration; exploration methods; mineral deposits; polymetallic ores; volcanogenic
deposits; sulphide deposits; base metals; tungsten; molybdenum; ore mineral genesis; mineralization; ore controls; heavy mineral samples; size fractionation; mineralogical analyses; glacial deposits; tills; till samples; glacial history; ice flow;
sediment dispersal; scanning electron microscope analyses; spectrometric analyses; alteration halos; mineral assemblages; inclusions; staurolite; gahnite; corundum; epidote; iron oxides; sulphides; scheelite; wolframite; molybdenite; bismuth;
software; bedrock geology; lithology; igneous rocks; intrusive rocks; granites; metamorphic rocks; greenstone belts; amphibolite facies; intrusions; plutons; dykes; sample preparation; Archean; Canadian Shield; Slave Province; Izok Lake Deposit;
Yellowknife Supergroup; Point Lake Formation; Contwoyto Formation; Sisson Deposit; Acadian Orogeny; Miramichi Group; Tetagouche Group; Methodology; Automation; ice-flow directions; Phanerozoic; Paleozoic; Devonian; Silurian; Ordovician; Cambrian;
Precambrian |
| Illustrations | location maps; geoscientific sketch maps; tables; schematic representations; bar graphs; photomicrographs; profiles |
| Program | Targeted Geoscience Initiative (TGI-5) Volcanic and sedimentary systems - volcanogenic massive sulphide ore systems |
| Released | 2022 01 27; 2022 11 17 |
| Abstract | Exploration under glacial sediment cover is a necessary part of modern mineral exploration in Canada. Traditional indicator methods use visual examination to identify mineral grains in the 250 to 2000
µm fraction of till heavy-mineral concentrates (HMC). This study tests automated mineralogical methods using scanning electron microscopy to identify indicator minerals in the fine (<250 µm) HMC fraction of till. Automated mineralogy of polished
grains from the fine HMC enables rapid data collection (10 000-300 000 grains/sample). Samples collected near two deposits were used to test this method: four from the upper-amphibolite facies Izok Lake volcanogenic massive-sulfide deposit, Nunavut,
and five from the Sisson granite-hosted W-Mo deposit, New Brunswick.
The less than 250 µm HMC fraction of till samples collected down ice of each deposit contain ore and alteration minerals typical of their deposit type. Sulfide minerals occur
mainly as inclusions in oxidation-resistant minerals, including minerals previously identified in each deposit's metamorphic alteration halo, and are found to occur farther down ice than the grains identified visually in the greater than 250 µm HMC
fraction. This project's workflow expands the detectable footprint for certain indicator minerals and enhances the information that can be collected from till samples. |
| Summary | (Plain Language Summary, not published)
The Targeted Geoscience Initiative (TGI) 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 contribution summarizes the results of a 5-year study of multiple mineral deposit types: polymetallic hyper-enriched
black shale; sedimentary exhalative Pb-Zn; carbonate-hosted Pb-Zn, magnesite; fracture-controlled replacement Zn-Pb, rare-earth element-F-Ba; and volcanogenic massive sulfides. Studies employed field geology, combined with geochemical
(lithogeochemistry, stable and radiogenic isotopes, fluid inclusions, and mineral chemistry) and geophysical (rock properties, magnetotelluric, and seismic) methods. Collectively, the research provides advanced genetic and exploration models for
volcanic- and sedimentary-hosted base-metal deposits, together with new laboratory, geophysical, and field techniques. |
| GEOSCAN ID | 328011 |
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