| Title | Application of pyrite chemistry to recognize a distal expression of hydrothermal activity in the MacMillan Pass SEDEX district, Yukon |
| Download | Download (whole publication) |
| Author | Leighton, C; Layton-Matthews, D; Peter, J M; Gadd, M G |
| Source | Targeted Geoscience Initiative: 2018 report of activities; by Rogers, N (ed.); Geological Survey of Canada, Open File 8549, 2019 p. 125-137, https://doi.org/10.4095/313646 (Open Access) |
| Year | 2019 |
| Publisher | Natural Resources Canada |
| Document | open file |
| Lang. | English |
| Media | on-line; digital |
| Related | This publication is contained in Rogers, N; (2019). Targeted
Geoscience Initiative: 2018 report of activities, Geological Survey of Canada, Open File 8549 |
| File format | pdf |
| Province | Yukon |
| NTS | 105I; 105J |
| Area | MacMillan Pass |
| Lat/Long WENS | -132.0000 -128.0000 63.0000 62.0000 |
| Subjects | economic geology; geochemistry; mineral deposits; lead; zinc; silver; barium; sedimentary ore deposits; volcanic exhalitive zone; volcano-sedimentary ore deposits; mineral exploration; ore mineral
genesis; mineralization; ore controls; pyrite; geochemical analyses; trace element analyses; mass spectrometer analysis; depositional environment; fluid dynamics; drillholes; mineral associations; morphology; sedimentary environment; diagenesis;
hydrothermal systems; metamorphism; mineral enrichment; mineral occurrences; barite; bedrock geology; lithology; sedimentary rocks; argillites; conglomerates; mudstones; sandstones; breccias; igneous rocks; intrusive rocks; felsic intrusive rocks;
monzonites; sulphide deposits; structural features; folds; anticlines; paragenesis; microscopic analysis; tectonic history; Tom Deposit; Jason Deposit; Selwyn Basin; ore systems approach; sedimentary exhalative (SEDEX) deposits; geochemical
signatures; Phanerozoic; Paleozoic; Carboniferous; Mississippian; Devonian |
| Illustrations | geoscientific sketch maps; lithologic sections; correlation sections; geochemical profiles; tables; photomicrographs; geochronological charts; schematic representations; geochemical plots |
| Program | Knowledge Management Coordination, Targeted Geoscience Initiative (TGI-5) |
| Program | Volcanogenic massive sulphide ore systems - deposition - time and space, Targeted Geoscience Initiative (TGI-5) |
| Released | 2019 03 01 |
| Abstract | The Tom and Jason sedimentary exhalative (SEDEX) Pb-Zn-Ag-(Ba) deposits in Yukon grade 7.4 weight % and 7.0 weight % Zn, and 6.5 weight % and 4.6 weight % Pb, with zinc and lead tonnages of 15.7 and
10.1 Mt, respectively. Pyrite is ubiquitous in SEDEX deposits and can potentially reveal much information about the environment and nature of deposition, hydrothermal fluid properties, genesis of mineralization, and may provide vectors toward
mineralization. Pyrite-bearing samples from three drillholes situated 2 to 4 km from mineralization (but time-stratigraphically equivalent) were sampled, and four generations of pyrite were identified (Py1, Py2, Py3, Py4), each with distinct
morphological characteristics and mineralogical associations. Synsedimentary (Py1), diagenetic (Py2), hydrothermal (Py3) and metamorphic (Py4) morphologies were identified. A representative subset of pyrite grains was analyzed for trace element
contents by laser ablation-inductively coupled plasma mass spectrometry using raster grids to create quantitative trace element composition maps, in order to characterize the trace element composition of each pyrite generation.
A distal (2-4 km)
expression of hydrothermal mineralization is recognized in Py3, which displays mineral associations and a trace element assemblage typical of hydrothermally precipitated pyrite. The trace element geochemistry of pyrite distal to SEDEX mineralization
(and time-stratigraphically equivalent to it) displays enrichment in Zn, Mn, As and Co, and these elements are generally more abundant in Py3 than other generations, indicating the presence of nearby concealed mineralization. |
| GEOSCAN ID | 313646 |
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